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Antonelli Rossi DA, De Araujo Junior JA, Luvizutto GJ, Bazan R, Salmazo PS, Modolo GP, Hueb JC, Nunes HRDC, Hokama NK, Minicucci MF, Roscani MG, Zanati Bazan SG. Effect of a Physical Exercise Program on the Inflammatory Response, Cardiac Functions, Functional Capacity, and Quality of Life in Patients with Sickle Cell Disease. J Clin Med 2023; 12:3952. [PMID: 37373647 DOI: 10.3390/jcm12123952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/13/2023] [Accepted: 06/03/2023] [Indexed: 06/29/2023] Open
Abstract
INTRODUCTION The beneficial effects of physical exercise on functional capacity and inflammatory response are well-known in cardiovascular diseases; however, studies on sickle cell disease (SCD) are limited. It was hypothesized that physical exercise may exert a favorable effect on the inflammatory response of SCD patients, contributing to an improved quality of life. This study aimed to evaluate the effect of a regular physical exercise program on the anti-inflammatory responses in SCD patients. METHODS A non-randomized clinical trial was conducted in adult SCD patients. The patients were divided into two groups: 1-Exercise Group, which received a physical exercise program three times a week for 8 weeks, and; 2-Control Group, with routine physical activities. All patients underwent the following procedures initially and after eight weeks of protocol: clinical evaluation, physical evaluation, laboratory evaluation, quality of life evaluation, and echocardiographic evaluation. STATISTICAL ANALYSIS Comparisons between groups were made using Student's t-test, Mann-Whitney test, chi-square test, or Fisher's exact test. Spearman's correlation coefficient was calculated. The significance level was set at p < 0.05. RESULTS There was no significant difference in inflammatory response between the Control and Exercise Groups. The Exercise Group showed an improvement in peak VO2 values (p < 0.001), an increase in the distance walked (p < 0.001), an improvement in the limitation domain due to the physical aspects of the 36-Item Short Form Health Survey (SF-36) quality of life questionnaire (p = 0.022), and an increase in physical activity related to leisure (p < 0.001) and walking (p = 0.024) in the International Physical Activity Questionnaire (IPAQ). There was a negative correlation between IL-6 values and distance walked on the treadmill (correlation coefficient -0.444, p = 0.020) and the estimated peak VO2 values (correlation coefficient -0.480; p = 0.013) in SCD patients in both groups. CONCLUSIONS The aerobic exercise program did not change the inflammatory response profile of SCD patients, nor did it show unfavorable effects on the parameters evaluated, and patients with lower functional capacity were those with the highest levels of IL-6.
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Affiliation(s)
| | - Jonas Alves De Araujo Junior
- Department of Internal Medicine, Botucatu Medical School-UNESP, São Paulo State University, Botucatu 18618-687, Brazil
| | - Gustavo José Luvizutto
- Department of Applied Physical Therapy, Federal University of Triângulo Mineiro, Uberaba 38065-430, Brazil
| | - Rodrigo Bazan
- Department of Neurology, Botucatu Medical School-UNESP, São Paulo State University, Botucatu 18618-970, Brazil
| | - Péricles Sidnei Salmazo
- Department of Medicine, Faculty of Medical and Health Sciences, Pontifical Catholic University of São Paulo, Sorocaba 18052-490, Brazil
| | - Gabriel Pinheiro Modolo
- Department of Neurology, Botucatu Medical School-UNESP, São Paulo State University, Botucatu 18618-970, Brazil
| | - João Carlos Hueb
- Department of Internal Medicine, Botucatu Medical School-UNESP, São Paulo State University, Botucatu 18618-687, Brazil
| | | | - Newton Key Hokama
- Department of Internal Medicine, Botucatu Medical School-UNESP, São Paulo State University, Botucatu 18618-687, Brazil
| | - Marcos Ferreira Minicucci
- Department of Internal Medicine, Botucatu Medical School-UNESP, São Paulo State University, Botucatu 18618-687, Brazil
| | - Meliza Goi Roscani
- Department of Medicine, Federal University of Sao Carlos-UFSCar, São Carlos 13565-251, Brazil
| | - Silméia Garcia Zanati Bazan
- Department of Internal Medicine, Botucatu Medical School-UNESP, São Paulo State University, Botucatu 18618-687, Brazil
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Deveci OS, Ozmen C, Karaaslan MB, Celik AI, Rahimova H, Akray A, Tepe O, Gurkan E, Deniz A. Increased Circulating Copeptin Levels Are Associated with Vaso-Occlusive Crisis and Right Ventricular Dysfunction in Sickle Cell Anemia. Med Princ Pract 2022; 31:47-53. [PMID: 34852350 PMCID: PMC8995666 DOI: 10.1159/000521216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 11/17/2021] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Vaso-occlusive crisis (VOC) is a common clinical manifestation of sickle cell anemia (SCA) and is associated with increased proinflammatory mediators. Copeptin is the C-terminal part of the prohormone for provasopressin and seems clinically relevant in various clinical conditions. Right ventricular (RV) dysfunction significantly appears in SCA patients due to pulmonary hypertension. This study aimed to investigate the association of copeptin levels in VOC patients and evaluate RV dysfunction. MATERIALS AND METHODS A total of 108 patients were enrolled in the study. Twenty-eight SCA patients in steady state (30.2 ± 0.9 years), 25 SCA patients in VOC (36.8 ± 11.8 years), and 55 healthy individuals (31.9 ± 9.4 years) with HbAA genotype were included. Clinical, echocardiographic, and laboratory data were recorded. ELISA was used for the determination of serum levels of copeptin. RESULTS VOC patients had significantly higher copeptin level compared both with controls and SCA subjects in steady state (22.6 ± 13.0 vs. 11.3 ± 5.7 pmol/L, 22.6 ± 13.0 vs. 12.4 ± 5.8 pmol/L, p = 0.009 for both). Additionally, the copeptin level was significantly higher in SCA patients with RV dysfunction than those without RV dysfunction (23.2 ± 12.2 vs. 15.3 ± 9.5 pmol/L, p = 0.024). Multiple logistic regression analysis revealed that high-sensitivity C-reactive protein and copeptin levels were found to be associated with VOC. CONCLUSION This study showed that copeptin and hs-CRP levels were increased in patients with VOC, and it was found that RV dysfunction was more common in SCA patients with VOC than in the control group. Copeptin can be considered for use as a potential biomarker in predicting VOC crisis in SCA patients and in the early detection of patients with SCA who have the potential to develop RV dysfunction.
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Affiliation(s)
- Onur Sinan Deveci
- Department of Cardiology, Faculty of Medicine, Cukurova University, Adana, Turkey
- *Onur Sinan Deveci,
| | - Caglar Ozmen
- Department of Cardiology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | | | - Aziz Inan Celik
- Department of Cardiology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | - Hatice Rahimova
- Department of Cardiology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | - Anil Akray
- Department of Cardiology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | - Omer Tepe
- Department of Cardiology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | - Emel Gurkan
- Department of Hematology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | - Ali Deniz
- Department of Cardiology, Faculty of Medicine, Cukurova University, Adana, Turkey
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Zeitoune R, Mogami R, Koifman ACB, Lopes AJ, Soares AR, Martins RAG, Maioli MCP. Diaphragm ultrasonography in adults with sickle cell anemia: evaluation of morphological and functional aspects. ACTA ACUST UNITED AC 2020; 25:372-382. [PMID: 33095119 DOI: 10.1080/16078454.2020.1833506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
OBJECTIVES To assess morphological and functional aspects of the diaphragm by ultrasonography (US) in adults with sickle cell anemia (SCA) and evaluate if the diaphragmatic musculature can play a role in changes found in pulmonary function tests (PFTs) of these patients. METHODS This is a cross-sectional observational and single-center study involving 40 adults with SCA who underwent diaphragm US and PFTs with a maximum of 1 month between the two tests. Diaphragm US was performed in B and M modes, and echogenicity, thickness and movement of the muscle was assessed in different respiratory maneuvers. RESULTS Diaphragms had preserved echogenicity and the thickness was not significantly different between the groups. The SCA group exhibited significantly higher movement of the right hemidiaphragm during deep breathing (p = 0.004) and the sniff test (p = 0.0008) and lower movement of the left hemidiaphragm during quiet breathing (p = 0.009). There was a predominance of restrictive pattern (65%) and a global reduction in respiratory muscle strength (RMS) (70%). CONCLUSIONS This study shows that adults with SCA had normal morphostructural aspects and absence of diaphragm dysfunction. Otherwise, they presented greater movement of the right hemidiaphragm during deep breathing and sniff test maneuvers. Despite the restrictive pattern and the reduction in RMS found in PFTs, the diaphragm of young adults with SCA did not have weakness or paralysis.
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Affiliation(s)
- Rachel Zeitoune
- Marinha do Brasil, São Paulo, Brazil.,Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brazil
| | - Roberto Mogami
- Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brazil
| | - Ana Celia Baptista Koifman
- Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brazil.,Universidade Federal do Estado do Rio de Janeiro (UNIRIO), Rio de Janeiro, Brazil
| | - Agnaldo Jose Lopes
- Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, Brazil.,Centro Universitário Augusto Motta (UNISUAM), Rio de Janeiro, Brazil
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The association of nocturnal hypoxia and an echocardiographic measure of pulmonary hypertension in children with sickle cell disease. Pediatr Res 2019; 85:506-510. [PMID: 30135591 DOI: 10.1038/s41390-018-0125-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 04/03/2018] [Accepted: 06/11/2018] [Indexed: 02/02/2023]
Abstract
BACKGROUND Pulmonary hypertension (PH) is multifactorial in origin and may develop early in children with sickle cell disease (C-SCD). Potential etiologies are hemolysis-induced endothelial dysfunction, left ventricular (LV) dysfunction, and chronic hypoxia. Nocturnal hypoxia (NH) in C-SCD is known to be a sequela of obstructive sleep apnea (OSA). The primary objective of this study is to correlate polysomnographic evidence NH with echocardiographic measures of PH in C-SCD. METHODS We performed a retrospective chart review of 20 C-SCD (Hemoglobin SS), who had polysomnography and echocardiogram performed within a narrow time interval, and 31% of them had pre-existing cardiac conditions. Tricuspid regurgitant jet velocity (TRJV) ≥ 2.5 m/s was considered as an indicator of PH. RESULTS Twenty-five percent of the subjects had NH. Forty percent of C-SCD, predominantly male, had evidence of PH based on an elevated TRJV. Children with NH compared to non-NH had significantly worse baseline hypoxemia (p < 0.001), higher TRJV (p = 0.005), and higher LV end-diastolic diameters (p = 0.009). The severity of NH was influenced by OSA. However, PH was not associated with OSA or duration of hydroxyurea therapy. CONCLUSION Our study indicates that NH is associated with PH in C-SCD, and that screening for NH may help to identify C-SCD with higher morbidity risk.
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Adekile AD, Azab AF, Owayed A, Khadadah M. Correlates of Pulmonary Function in Children with Sickle Cell Disease and Elevated Fetal Hemoglobin. Med Princ Pract 2018; 27:49-54. [PMID: 29183008 PMCID: PMC5968263 DOI: 10.1159/000485801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 11/28/2017] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE The current study was carried out to compare pulmonary function tests (PFTs) in pediatric Kuwaiti sickle cell disease (SCD) patients to age-matched normal controls and to investigate the association of PFTs with selected clinical and laboratory parameters. Subjects andMethods: There were 38 patients with SCD and 36 controls in the study. The patients were recruited from the Pediatric Hematology Clinics of Mubarak Al-Kabeer and Al-Amiri Hospitals, Kuwait, and were studied in steady state. The controls were healthy, non-sickle cell siblings of the patients. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), total lung capacity, and other PFT parameters were obtained using a constant-volume, variable-pressure, body plethysmograph. Hemoglobin, fetal hemoglobin, serum bilirubin, and lactate dehydrogenase were determined using standard methods. RESULTS The mean ages of the patients and controls were 10.5 ± 3.2 and 10.5 ± 3.5 years, respectively. The FEV1% predicted of 84.1 ± 15.4% among the patients was significantly lower than the 92.1 ± 11.8% in the controls (p = 0.003). The FVC% predicted was also significantly lower (p = 0.022) in the patients than in the controls, although the values were generally within the normal range. There was no association of FEV1 with pain phenotype, acute chest syndrome (ACS), or blood transfusions. Also, there was no significant correlation with reticulocytes, bilirubin, or lactate dehydrogenase. CONCLUSIONS In this study, changes in PFT, especially FEV1, developed early in the SCD patients. There was no demonstrable association with frequent vaso-occlusive crisis, ACS, and other variables. Hence, there is a need for follow-up studies with serial PFTs to identify vulnerable patients, who might need intervention to prevent early mortality.
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Affiliation(s)
- Adekunle D. Adekile
- Department of Pediatrics, Kuwait University, Safat, Kuwait
- Department of Pediatric Hematology Unit, Mubarak Hospital, Safat, Kuwait
- *Prof. Adekunle D. Adekile, Department of Pediatrics, Faculty of Medicine, Kuwait University, PO Box 24923, Safat 13110 (Kuwait), E-Mail
| | - Asmaa Farag Azab
- Department of Pediatric Hematology Unit, Mubarak Hospital, Safat, Kuwait
| | | | - Mousa Khadadah
- Department of Medicine, Faculty of Medicine, Kuwait University, Safat, Kuwait
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Thein MS, Igbineweka NE, Thein SL. Sickle cell disease in the older adult. Pathology 2017; 49:1-9. [PMID: 27914684 PMCID: PMC10757825 DOI: 10.1016/j.pathol.2016.10.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 10/12/2016] [Accepted: 10/20/2016] [Indexed: 01/14/2023]
Abstract
Sickle cell disease (SCD) is an inherited haemoglobin disorder, associated with recurrent painful episodes, ongoing haemolytic anaemia and progressive multi-organ damage. Until the early 1990s, survival beyond the fourth decade for a patient with SCD was considered unusual and prompted case reports. Nowadays, in countries with developed health care systems, more than 90 percent of newborns with SCD survive into adulthood. Nevertheless, their life expectancy is still shortened by more than two decades compared to the general population. With an increasing life expectancy, SCD has now evolved into a debilitating disorder with substantial morbidity resulting from ongoing sickle cell vasculopathy and multi-organ damage. Limited data on health care issues of older adults with SCD poses multiple challenges to patients, their families and health care providers. In this review, we will address and discuss acute and chronic complications of SCD with a special focus on the older adult.
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Affiliation(s)
- Mya S Thein
- Sickle Cell Branch, National Heart Lung and Blood Institute, National Institute of Health, Bethesda, MD, USA
| | - Norris E Igbineweka
- Department of Haematology, Brighton and Sussex Medical School, University of Sussex, Brighton, United Kingdom
| | - Swee Lay Thein
- Sickle Cell Branch, National Heart Lung and Blood Institute, National Institute of Health, Bethesda, MD, USA.
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Martí-Carvajal AJ, Conterno LO. Antibiotics for treating community-acquired pneumonia in people with sickle cell disease. Cochrane Database Syst Rev 2016; 11:CD005598. [PMID: 27841444 PMCID: PMC6530651 DOI: 10.1002/14651858.cd005598.pub4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND As a consequence of their condition, people with sickle cell disease are at high risk of developing an acute infection of the pulmonary parenchyma called community-acquired pneumonia. Many different bacteria can cause this infection and antibiotic treatment is generally needed to resolve it. There is no standardized approach to antibiotic therapy and treatment is likely to vary from country to country. Thus, there is a need to identify the efficacy and safety of different antibiotic treatment approaches for people with sickle cell disease suffering from community-acquired pneumonia. This is an update of a previously published Cochrane Review. OBJECTIVES To determine the efficacy and safety of the antibiotic treatment approaches (monotherapy or combined) for people with sickle cell disease suffering from community-acquired pneumonia. SEARCH METHODS We searched The Group's Haemoglobinopathies Trials Register (01 September 2016), which comprises references identified from comprehensive electronic database searches and handsearching of relevant journals and abstract books of conference proceedings. We also searched LILACS (1982 to 01 September 2016), African Index Medicus (1982 to 20 October 2016) and WHO ICT Registry (20 October 2016). SELECTION CRITERIA We searched for published or unpublished randomized controlled trials. DATA COLLECTION AND ANALYSIS We intended to summarise data by standard Cochrane methodologies, but no eligible randomized controlled trials were identified. MAIN RESULTS We were unable to find any randomized controlled trials on antibiotic treatment approaches for community-acquired pneumonia in people with sickle cell disease. AUTHORS' CONCLUSIONS The updated review was unable to identify randomized controlled trials on efficacy and safety of the antibiotic treatment approaches for people with sickle cell disease suffering from community-acquired pneumonia. Randomized controlled trials are needed to establish the optimum antibiotic treatment for this condition. The trials regarding this issue should be structured and reported according to the CONSORT statement for improving the quality of reporting of efficacy and improved reports of harms in clinical research. Triallists should consider including the following outcomes in new trials: number of days to become afebrile; mortality; onset of pain crisis or complications of sickle cell disease following community-acquired pneumonia; diagnosis; hospitalization (admission rate and length of hospital stay); respiratory failure rate; and number of participants receiving a blood transfusion.There are no trials included in the review and we have not identified any relevant trials up to September 2016. We therefore do not plan to update this review until new trials are published.
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Musa BM, Galadanci NA, Coker M, Bussell S, Aliyu MH. The global burden of pulmonary hypertension in sickle cell disease: a systematic review and meta-analysis. Ann Hematol 2016; 95:1757-64. [PMID: 27181705 DOI: 10.1007/s00277-016-2693-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 05/09/2016] [Indexed: 01/18/2023]
Abstract
Elevated tricuspid regurgitant jet velocity (TRJV) is a surrogate measure of pulmonary hypertension (PH) in persons with sickle cell disease (SCD). We sought to estimate the burden of PH in people living with sickle cell disease based on TRJV. From 2000 to 2015, we searched electronic databases for eligible publications and included 29 studies (n = 5358 persons). We used random effects modeling to determine the pooled estimate of elevated TRJV. The overall pooled prevalence of elevated TRJV was 23.5 %(95 % CI 19.5-27.4) in persons with SCD. The pooled prevalence of elevated TRJV in children and adults with SCD was 20.7 % (95 % CI 15.7--25.6) and 24.4 % (95 % CI 18.4-30.4), respectively. TRJV is prevalent among adults and children with SCD. Our finding support international recommendations that call for screening for PH in SCD patients.
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Affiliation(s)
- B M Musa
- Department of Medicine, Bayero University/Aminu Kano Teaching Hospital, Kano, Nigeria.
| | - N A Galadanci
- Department of Hematology, Bayero University/Aminu Kano Teaching Hospital, Kano, Nigeria
| | - M Coker
- Institute of Human Virology, University of Maryland, Baltimore, USA
| | - S Bussell
- Vanderbilt Institute for Global Health, Vanderbilt University School of Medicine, Nashville, TN, USA.,Department of Preventive Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - M H Aliyu
- Vanderbilt Institute for Global Health, Vanderbilt University School of Medicine, Nashville, TN, USA.,Department of Preventive Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA.,Departments of Family and Community Medicine, Meharry Medical College, Nashville, USA
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Adly AA, Ismail EA, Andrawes NG, Mahmoud MM, Eladawy R. Soluble Fas/FasL ratio as a marker of vasculopathy in children and adolescents with sickle cell disease. Cytokine 2016; 79:52-8. [PMID: 26765484 DOI: 10.1016/j.cyto.2015.12.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 12/12/2015] [Accepted: 12/29/2015] [Indexed: 01/19/2023]
Abstract
OBJECTIVES Sickle cell disease (SCD) is characterized by chronic inflammation due to ischemic tissue damage, accentuated during acute complications. Fas and its ligand (FasL) are members of tumor necrosis factor receptor superfamily and a major pathway for induction of apoptosis. Fas/FasL interactions may be related to augmentation of inflammatory response. We assessed the levels of sFas and sFasL in 35 children and adolescents with SCD compared with 35 healthy controls in relation to hemolysis, iron overload, sickle vasculopathy including kidney disease. METHODS SCD patients, in steady state and asymptomatic for pulmonary hypertension, were studied stressing on hydroxyurea therapy, serum ferritin, urinary albumin creatinine ratio (UACR), high-sensitivity C-reactive protein (hs-CRP) and sFas/sFasL levels. RESULTS sFas/sFasL ratio was significantly higher in patients compared with controls. sFas/sFasL ratio was elevated in patients with pulmonary hypertension, nephropathy and those who had history of frequent sickling crisis or serum ferritin ⩾2500. SCD patients treated with hydroxyurea had lower sFas/sFasL ratio than untreated patients. sFas/sFasL ratio was positively correlated to transfusion index, white blood cells, hs-CRP, serum ferritin and UACR. The cutoff value of sFas/sFasL at 8.75pg/mL could differentiate SCD patients with and without nephropathy while the cutoff value at 22pg/mL could differentiate SCD patients with and without pulmonary hypertension risk with high sensitivity and specificity. CONCLUSION sFas/sFasL ratio may be considered as a marker for vascular dysfunction in SCD patients and is related to inflammation, iron overload and albuminuria level. Thus, it may be a reliable method to assess renal impairment in SCD.
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Affiliation(s)
- Amira A Adly
- Department of Pediatric, Faculty of Medicine, Ain Shams University, Egypt
| | - Eman A Ismail
- Department of Clinical Pathology, Faculty of Medicine, Ain Shams University, Egypt.
| | - Nevine G Andrawes
- Department of Pediatric, Faculty of Medicine, Ain Shams University, Egypt
| | - Mai M Mahmoud
- Department of Pediatric, Faculty of Medicine, Ain Shams University, Egypt
| | - Rasha Eladawy
- Department of Pediatric, Faculty of Medicine, Ain Shams University, Egypt
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Maioli MCP, Soares AR, Bedirian R, Alves UD, de Lima Marinho C, Lopes AJ. Relationship between pulmonary and cardiac abnormalities in sickle cell disease: implications for the management of patients. Rev Bras Hematol Hemoter 2015; 38:21-7. [PMID: 26969771 PMCID: PMC4786771 DOI: 10.1016/j.bjhh.2015.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Revised: 10/23/2015] [Accepted: 11/07/2015] [Indexed: 12/20/2022] Open
Abstract
Objective To evaluate the association between clinical, pulmonary, and cardiovascular findings in patients with sickle cell disease and, secondarily, to compare these findings between sickle cell anemia patients and those with other sickle cell diseases. Methods Fifty-nine adults were included in this cross-sectional study; 47 had sickle cell anemia, and 12 had other sickle cell diseases. All patients underwent pulmonary function tests, chest computed tomography, and echocardiography. Results Abnormalities on computed tomography, echocardiography, and pulmonary function tests were observed in 93.5%, 75.0%; and 70.2% of patients, respectively. A higher frequency of restrictive abnormalities was observed in patients with a history of acute chest syndrome (85% vs. 21.6%; p-value < 0.0001) and among patients with increased left ventricle size (48.2% vs. 22.2%; p-value = 0.036), and a higher frequency of reduced respiratory muscle strength was observed in patients with a ground-glass pattern (33.3% vs. 4.3%; p-value = 0.016). Moreover, a higher frequency of mosaic attenuation was observed in patients with elevated tricuspid regurgitation velocity (61.1% vs. 24%; p-value = 0.014). Compared to patients with other sickle cell diseases, sickle cell anemia patients had suffered increased frequencies of acute pain episodes, and acute chest syndrome, and exhibited mosaic attenuation on computed tomography, and abnormalities on echocardiography. Conclusion A significant interrelation between abnormalities of the pulmonary and cardiovascular systems was observed in sickle cell disease patients. Furthermore, the severity of the cardiopulmonary parameters among patients with sickle cell anemia was greater than that of patients with other sickle cell diseases.
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Affiliation(s)
| | | | - Ricardo Bedirian
- Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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Tantawy AAG, Adly AAM, Ismail EAR, Aly SH. Endothelial nitric oxide synthase gene intron 4 VNTR polymorphism in sickle cell disease: relation to vasculopathy and disease severity. Pediatr Blood Cancer 2015; 62:389-94. [PMID: 25263931 DOI: 10.1002/pbc.25234] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 07/28/2014] [Indexed: 02/02/2023]
Abstract
BACKGROUND Impaired NO bioavailability represents the central feature of endothelial dysfunction, and is a common denominator in the pathogenesis of vasculopathy in sickle cell disease (SCD). Evidence indicates the contribution of 4a allele of endothelial NO synthase (eNOS) gene to cardiac and renal diseases. We studied the 27-base pair tandem repeat polymorphism in intron 4 of eNOS gene in 51 patients with SCD compared with 55 healthy controls and evaluated its role in disease severity and hemolysis-associated complications. PROCEDURE Transfusion history, vaso-occlusive crisis, thrombotic events, urinary albumin excretion, and echocardiography were assessed. Analysis of eNOS intron 4 gene polymorphism was performed by polymerase chain reaction. RESULTS The distribution of eNOS alleles and genotypes was similar between patients with SCD and controls. Compared with bb genotype, the frequency of eNOS4a allele (aa and ab genotypes) was significantly higher in patients with elevated tricuspid regurgitant velocity (TRV) (P = 0.009), nephropathy (P = 0.006), or history of cerebral stroke (P = 0.029). Logistic regression analysis revealed that eNOS4a allele was an independent risk factor for elevated TRV (P < 0.001). Patients with SCD and eNOS4a allele had higher lactate dehydrogenase, serum ferritin, D-Dimer, and von Willebrand factor antigen (P < 0.05). CONCLUSIONS We suggest that eNOS intron 4 gene polymorphism is related to endothelial dysfunction and vasculopathy in SCD and could provide utility for prediction of increased susceptibility to vascular complications.
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Elevated tricuspid regurgitant velocity as a marker for pulmonary hypertension in children with sickle cell disease: less prevalent and predictive than previously thought? J Pediatr Hematol Oncol 2015; 37:134-9. [PMID: 24942020 DOI: 10.1097/mph.0000000000000184] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Although elevated tricuspid regurgitant velocity (TRV), an echocardiographic marker for pulmonary hypertension, has previously been tied to mortality in adult patients with sickle cell disease, recent data demonstrated that it correlates poorly with catheterization findings. We describe the largest echocardiographic evaluation of pediatric patients with sickle cell disease to date, specifically the results of a protocol whereby a TRV≥250 cm/s prompted further evaluation. We investigated if elevated TRV would independently identify patients at risk for increased morbidity. A clinical echocardiographic database containing 630 patients with sickle cell disease was retrospectively reviewed; 120 patients (19%) met inclusion criteria and were compared 1:1 to randomly selected age-matched controls from the same database. By multivariate analysis, the elevated TRV cohort did not differ from controls in likelihood of acute chest episodes, hospitalization, or stroke. The study cohort's mean TRV in fact decreased to 242±33 cm/s at follow-up without a discernible and comprehensive intervention to explain the improvement. Three patients had catheterization-proven pulmonary hypertension. In conclusion, elevated TRV in children with sickle cell disease is less prevalent than previously thought and is not independently associated with increased short-term morbidity.
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Bhatia M, Kolva E, Cimini L, Jin Z, Satwani P, Savone M, George D, Garvin J, Paz ML, Briamonte C, Cruz-Arrieta E, Sands S. Health-related quality of life after allogeneic hematopoietic stem cell transplantation for sickle cell disease. Biol Blood Marrow Transplant 2015; 21:666-72. [PMID: 25559691 DOI: 10.1016/j.bbmt.2014.12.007] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 12/08/2014] [Indexed: 01/04/2023]
Abstract
Sickle cell disease (SCD) is a hereditary hemoglobinopathy that affects over 100,000 people in the United States. Patients with SCD are known to experience suboptimal health-related quality of life (HRQoL). In addition to the physical manifestations of SCD, psychological and social stress, along with academic difficulties, secondary to the chronicity of the disease and its complications often affect patients with SCD. Although medical therapy of SCD has improved, allogeneic hematopoietic cell transplantation (allo-HCT) remains the only curative therapy. The objective of this study was to measure HRQoL before and after allo-HCT by assessing physical, psychological, and social functioning in patients with SCD who have undergone reduced-toxicity conditioning (busulfan/fludarabine/alemtuzumab) followed by allo-HCT. Patients < 21 years of age undergoing allo-HCT (matched siblings and unrelated donors) for SCD and their primary caregiver were enrolled using either the English or Spanish version of the PedsQoL 4.0. Data were collected at 3 time points: before allo-HCT and on days 180 and 365 after allo-HCT. The change in HRQoL from baseline was assessed with unadjusted and adjusted mixed-effects models in which subjects were treated as random effects, and variance component structure was used. Seventeen patients and 23 primary caregivers were enrolled and reported a mean overall HRQoL of 66.05 (SD, 15.62) and 72.20 (SD, 15.50) at baseline, respectively. In the patient-reported analysis with adjusted mixed-effects models, the estimated improvements in overall HRQoL were 4.45 (SE, 4.98; P = .380) and 16.58 (SE, 5.06; P = .003) at 180 and 365 days, respectively, after allo-HCT. For parent-reported overall HRQoL, the estimated improvements were 1.57 (SE, 4.82; P = .747) and 9.28 (SE, 4.62; P = .053) at 180 and 365 days, respectively, after allo-HCT. Similar results were found across the physical, social, and emotional HRQoL domains with mixed-effects models after adjustment of demographic and medical variables. In addition to the alleviation of clinical manifestations of SCD, these patients demonstrated significant improvement in most aspects of HRQoL by 1 year after allo-HCT. These data represent the trajectory of HRQoL during the initial year of follow-up within this population and should be integrated into the decision-making process when considering allo-HCT in patients with SCD.
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Affiliation(s)
- Monica Bhatia
- Division of Pediatric Hematology, Oncology and Stem Cell Transplantation, Columbia University Medical Center, New York, New York
| | - Elissa Kolva
- Department of Psychology, Fordham University, New York, New York
| | - Laura Cimini
- Department of School Psychology, Teachers College, Columbia University, New York, New York
| | - Zhezhen Jin
- Department of Biostatistics, Columbia University, New York, New York
| | - Prakash Satwani
- Division of Pediatric Hematology, Oncology and Stem Cell Transplantation, Columbia University Medical Center, New York, New York
| | - Mirko Savone
- Division of Pediatric Hematology, Oncology and Stem Cell Transplantation, Columbia University Medical Center, New York, New York
| | - Diane George
- Division of Pediatric Hematology, Oncology and Stem Cell Transplantation, Columbia University Medical Center, New York, New York
| | - James Garvin
- Division of Pediatric Hematology, Oncology and Stem Cell Transplantation, Columbia University Medical Center, New York, New York
| | - Mary Llenell Paz
- Department of Biobehavioral Sciences, Teachers College, Columbia University, New York, New York
| | - Courtney Briamonte
- Division of Pediatric Hematology, Oncology and Stem Cell Transplantation, Columbia University Medical Center, New York, New York
| | - Eduvigis Cruz-Arrieta
- Division of Pediatric Hematology, Oncology and Stem Cell Transplantation, Columbia University Medical Center, New York, New York
| | - Stephen Sands
- Division of Pediatric Hematology, Oncology and Stem Cell Transplantation, Columbia University Medical Center, New York, New York.
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Kim HC. Red cell exchange: special focus on sickle cell disease. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2014; 2014:450-456. [PMID: 25696893 DOI: 10.1182/asheducation-2014.1.450] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The primary function of red blood cells (RBCs) is to deliver oxygen from the lungs to tissues. Tissue hypoxia occurs when the oxygen-carrying capacity of RBCs is compromised due primarily to 3 causes: (1) a reduction in circulating RBC mass, (2) an increase in circulating RBC mass, or (3) abnormal hemoglobin (Hb) that either does not sufficiently release oxygen to tissues (high-oxygen-affinity hemoglobin) or occludes the microvasculature due to deformed RBCs (sickled RBCs). To improve oxygenation in patients with reduced or increased RBC mass, RBC administration (simple transfusion) or RBC removal (RBC depletion) is performed, respectively. However, for patients with abnormal Hb, RBCs containing abnormal Hb are removed and replaced by healthy volunteer donor RBCs by red cell exchange (RCE). RCE can be performed by manual exchange or by automated exchange using a blood cell separator (erythrocytapheresis). In this review, indications for RCE in sickle cell disease using the evidence-based American Society for Apheresis categories(1) are presented and the rationale for RCE in each disorder are discussed. Simple transfusion versus RCE and manual RCE versus automated RCE are compared. Finally, this review briefly presents some of the challenges of performing erythrocytapheresis in small children and discusses various choices for central venous access during RCE.(2.)
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Affiliation(s)
- Haewon C Kim
- Children's Hospital of Philadelphia, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
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MicroRNA 648 Targets ET-1 mRNA and is cotranscriptionally regulated with MICAL3 by PAX5. Mol Cell Biol 2014; 35:514-28. [PMID: 25403488 DOI: 10.1128/mcb.01199-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Pulmonary hypertension (PHT) is associated with high mortality in sickle cell anemia (SCA). Previously, we showed that elevated levels of placenta growth factor (PlGF) in SCA patients correlate with increased levels of the potent vasoconstrictor endothelin-1 (ET-1) and PHT. Moreover, PlGF induced the expression of ET-1 via hypoxia-inducible factor 1α. Here, we show a novel example of ET-1 posttranscriptional regulation by PlGF via action of microRNA 648 (miR-648), which is subject to transcriptional coregulation with its host gene, MICAL3 (microtubule-associated monooxygenase, calponin, and LIM domain containing 3gene). PlGF repressed expression of miR-648 in endothelial cells. Luciferase reporter assays using wild-type and mutant ET-1 3' untranslated region (UTR) constructs, and transfection of miR-648 mimics showed that miR-648 targets the 3' UTR of ET-1 mRNA. Since miR-648 is located in a 5'-proximal intron of MICAL3, we examined which of three potential promoters was responsible for its expression. The MICAL3 distal promoter (P1) was the predominant promoter used for transcription of pre-miR-648, and it was under positive control by PAX5 (paired box protein 5) transcription factor, as demonstrated by the loss and gain of function of PAX5 activity, and chromatin immunoprecipitation analysis. These studies provide a novel link wherein PlGF-mediated downregulation of PAX5 attenuates miR-648 expression leading to increased ET-1 levels that are known to induce PHT in SCA.
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Soluble CD163 in young sickle cell disease patients and their trait siblings: a biomarker for pulmonary hypertension and vaso-occlusive complications. Blood Coagul Fibrinolysis 2013; 23:640-8. [PMID: 22885767 DOI: 10.1097/mbc.0b013e3283573a42] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
CD163 is expressed on cells of monocyte-macrophage lineage and is the main hemoglobin-haptoglobin receptor. Inflammation and monocyte activation are predisposing factors to vaso-occlusion and pulmonary hypertension, which are serious complications in sickle cell disease (SCD). Siblings of SCD patients may have the same pathophysiology without displaying symptoms. We assessed soluble CD163 (sCD163) levels in 60 children with SCD and 30 sickle cell trait (SCT) siblings compared with 30 healthy controls as a potential marker for disease severity and treatment response. Patients were studied stressing on the presence of pulmonary hypertension by Dopplar-Echocardiography, sickling crisis, transfusion requirements, hydroxyurea response, hematological profile, high sensitivity C-reactive protein (hs-CRP) and serum sCD163. sCD163 was significantly elevated in SCD patients and SCT siblings compared with controls and the highest levels were in untreated SCD patients (P < 0.001). sCD163 was higher in patients with pulmonary hypertension, acute chest syndrome or stroke as well as in patients who developed sickling crisis during the study period (P < 0.05). Hydroxyurea-treated patients had lower sCD163 compared with untreated patients (P < 0.001). sCD163 was positively correlated to leukocyte count, HbS, hs-CRP, pulmonary artery pressure and tricuspid regurgitant velocity whereas inversely correlated to hemoglobin and HbF levels. The cut-off value of sCD163 at 1400 ng/ml could be considered a predictor for vaso-occlusive crisis in SCD with a sensitivity of 92.3% and specificity of 94.1%. sCD163 can be considered a biomarker for pulmonary hypertension, early crisis prediction and monitoring hydroxyurea response in SCD patients. Elevated sCD163 in trait siblings could reflect increased risk of sickling in challenging situations.
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Tantawy AAG, Adly AAM, Ismail EAR, Habeeb NM, Farouk A. Circulating platelet and erythrocyte microparticles in young children and adolescents with sickle cell disease: Relation to cardiovascular complications. Platelets 2012; 24:605-14. [DOI: 10.3109/09537104.2012.749397] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Myocardial infarction in sickle cell disease: use of translational imaging to diagnose an under-recognized problem. J Cardiovasc Transl Res 2012. [PMID: 23179134 DOI: 10.1007/s12265-012-9426-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Sickle cell disease (SCD) is an inherited disorder in which microvascular occlusion causes complications across multiple organ systems. The precise incidence of myocardial ischemia and infarction (MI), potentially under-recognized microvascular disease-related complications, remains unknown. The absence of typical atherosclerotic lesions seen in other patients with MI suggests a microvascular mechanism of myocardial injury. Cardiac magnetic resonance (CMR) can demonstrate microvascular disease, making it an appealing modality to assess symptomatic SCD patients. We demonstrate in several dramatic instances how CMR is uniquely able to depict cardiac microvascular obstruction in patients with SCD and chest pain, without which the possibility of myocardial injury would almost certainly be otherwise neglected. Much remains unknown regarding ischemic heart disease in patients with SCD including prevalence, detection, and management. Further work to define evaluation and management algorithms for chest pain in SCD and to develop risk assessment tools may reduce sudden cardiac death in this population.
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Martí-Carvajal AJ, Conterno LO. Antibiotics for treating community acquired pneumonia in people with sickle cell disease. Cochrane Database Syst Rev 2012; 10:CD005598. [PMID: 23076916 DOI: 10.1002/14651858.cd005598.pub3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND As a consequence of their condition, people with sickle cell disease are at high risk of developing an acute infection of the pulmonary parenchyma called community-acquired pneumonia. Many different bacteria can cause this infection and antibiotic treatment is generally needed to resolve it. There is no standardized approach to antibiotic therapy and treatment is likely to vary from country to country. Thus, there is a need to identify the efficacy and safety of different antibiotic treatment approaches for people with sickle cell disease suffering from community-acquired pneumonia. OBJECTIVES To determine the efficacy and safety of the antibiotic treatment approaches (monotherapy or combined) for people with sickle cell disease suffering from community-acquired pneumonia. SEARCH METHODS We searched The Group's Haemoglobinopathies Trials Register (25 May 2012), which comprises references identified from comprehensive electronic database searches and handsearching of relevant journals and abstract books of conference proceedings. We also searched LILACS (1982 to 27 April 2012), African Index Medicus (1982 to 27 April 2012) and WHO ICT Registry (27 April 2012). SELECTION CRITERIA We searched for published or unpublished randomized controlled trials. DATA COLLECTION AND ANALYSIS We intended to summarise data by standard Cochrane Collaboration methodologies, but no eligible randomized controlled trials were identified. MAIN RESULTS We were unable to find any randomized controlled trials on antibiotic treatment approaches for community-acquired pneumonia in people with sickle cell disease. AUTHORS' CONCLUSIONS The updated review was unable to identify randomized controlled trials on efficacy and safety of the antibiotic treatment approaches for people with sickle cell disease suffering from community-acquired pneumonia. Randomized controlled trials are needed to establish the optimum antibiotic treatment for this condition. The trials regarding this issue should be structured and reported according to the CONSORT statement for improving the quality of reporting of efficacy and improved reports of harms in clinical research. Triallists should consider including the following outcomes in new trials: number of days to become afebrile; mortality; onset of pain crisis or complications of SCD following CAP; diagnosis; hospitalisation (admission rate and length of hospital stay); respiratory failure rate; and number of participants receiving a blood transfusion.There are no trials included in the review and we have not identified any relevant trials up to May 2012. We therefore do not plan to update this review until new trials are published.
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Affiliation(s)
- Arturo J Martí-Carvajal
- Facultad de Ciencias de la Salud Eugenio Espejo, Universidad Tecnológica Equinoccial, Quito, Ecuador.
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Misclassification of pulmonary hypertension in adults with sickle hemoglobinopathies using Doppler echocardiography. South Med J 2012; 105:300-5. [PMID: 22665152 DOI: 10.1097/smj.0b013e318256b55b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To compare the diagnostic utility of Doppler echocardiography-derived tricuspid regurgitant jet velocity (TRV) ≥ 2.5 m/s to right heart catheterization (RHC) in defining pulmonary hypertension (PH) in adult patients with sickle cell disease (SCD). METHODS This is a retrospective chart review of adults with SCD who had a TRV ≥ 2.5 m/s and RHC. A TRV ≥ 2.5 m/s is suggestive of PH. Pulmonary arterial hypertension (PAH) was defined as a mean pulmonary artery pressure (mPAP) ≥ 25 mm Hg and pulmonary capillary wedge pressure ≤ 15 mm Hg. Pulmonary venous hypertension was defined as an mPAP ≥ 25 mm Hg and pulmonary capillary wedge pressure >15 mm Hg. RESULTS Twenty-five patients with SCD met the inclusion criteria. Nine of the 25 (36%) patients had an mPAP ≥ 25 mm Hg. Of these 9, 3 (33%) had PAH and 6 (66%) had pulmonary venous hypertension. Patients with PH did not have a higher TRV (3.1 ± 0.68 vs 2.70 ± 0.16 m/s; P = 0.12), but they did have higher cardiac outputs (10.4 ± 2.7 vs 7.81 ± 1.85 L/min; P = 0.012. The specificity of TRV equal to 2.51 m/s in diagnosing PH was 18.8%. At a TRV of 2.88 m/s, the specificity increased to 81%. CONCLUSIONS In adults with SCD, a TRV of 2.5 m/s lacks specificity for use as a screening tool in the diagnosis of PH. Using a TRV of ≥ 2.88 m/s allows the TRV to be used as a screening tool and reduces the false-positive rate and need for unnecessary RHC.
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Ballas SK, Kesen MR, Goldberg MF, Lutty GA, Dampier C, Osunkwo I, Wang WC, Hoppe C, Hagar W, Darbari DS, Malik P. Beyond the definitions of the phenotypic complications of sickle cell disease: an update on management. ScientificWorldJournal 2012; 2012:949535. [PMID: 22924029 PMCID: PMC3415156 DOI: 10.1100/2012/949535] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 04/01/2012] [Indexed: 12/25/2022] Open
Abstract
The sickle hemoglobin is an abnormal hemoglobin due to point mutation (GAG → GTG) in exon 1 of the β globin gene resulting in the substitution of glutamic acid by valine at position 6 of the β globin polypeptide chain. Although the molecular lesion is a single-point mutation, the sickle gene is pleiotropic in nature causing multiple phenotypic expressions that constitute the various complications of sickle cell disease in general and sickle cell anemia in particular. The disease itself is chronic in nature but many of its complications are acute such as the recurrent acute painful crises (its hallmark), acute chest syndrome, and priapism. These complications vary considerably among patients, in the same patient with time, among countries and with age and sex. To date, there is no well-established consensus among providers on the management of the complications of sickle cell disease due in part to lack of evidence and in part to differences in the experience of providers. It is the aim of this paper to review available current approaches to manage the major complications of sickle cell disease. We hope that this will establish another preliminary forum among providers that may eventually lead the way to better outcomes.
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Affiliation(s)
- Samir K Ballas
- Cardeza Foundation and Department of Medicine, Thomas Jefferson University, 1015 Walnut Street, Philadelphia, PA 19107, USA.
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Garrido VT, Proença-Ferreira R, Dominical VM, Traina F, Bezerra MAC, Mello MRB, Colella MP, Araújo AS, Saad STO, Costa FF, Conran N. Elevated plasma levels and platelet-associated expression of the pro-thrombotic and pro-inflammatory protein, TNFSF14 (LIGHT), in sickle cell disease. Br J Haematol 2012; 158:788-97. [DOI: 10.1111/j.1365-2141.2012.09218.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 05/28/2012] [Indexed: 11/28/2022]
Affiliation(s)
- Vanessa T. Garrido
- INCT de Sangue, Haematology and Haemotherapy Centre; School of Medicine; University of Campinas -UNICAMP; Campinas; SP; Brazil
| | - Renata Proença-Ferreira
- INCT de Sangue, Haematology and Haemotherapy Centre; School of Medicine; University of Campinas -UNICAMP; Campinas; SP; Brazil
| | - Venina M. Dominical
- INCT de Sangue, Haematology and Haemotherapy Centre; School of Medicine; University of Campinas -UNICAMP; Campinas; SP; Brazil
| | - Fabiola Traina
- INCT de Sangue, Haematology and Haemotherapy Centre; School of Medicine; University of Campinas -UNICAMP; Campinas; SP; Brazil
| | - Marcos A. C. Bezerra
- Centro de Ciências Biológicas; Universidade Federal de Pernambuco; Recife; PE; PE; Brazil
| | - Mariana R. B. Mello
- INCT de Sangue, Haematology and Haemotherapy Centre; School of Medicine; University of Campinas -UNICAMP; Campinas; SP; Brazil
| | - Marina P. Colella
- INCT de Sangue, Haematology and Haemotherapy Centre; School of Medicine; University of Campinas -UNICAMP; Campinas; SP; Brazil
| | - Aderson S. Araújo
- Haematology and Haemotherapy Foundation of Pernambuco (HEMOPE); Recife; PE; Brazil
| | - Sara T. O. Saad
- INCT de Sangue, Haematology and Haemotherapy Centre; School of Medicine; University of Campinas -UNICAMP; Campinas; SP; Brazil
| | - Fernando F. Costa
- INCT de Sangue, Haematology and Haemotherapy Centre; School of Medicine; University of Campinas -UNICAMP; Campinas; SP; Brazil
| | - Nicola Conran
- INCT de Sangue, Haematology and Haemotherapy Centre; School of Medicine; University of Campinas -UNICAMP; Campinas; SP; Brazil
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Forrest S, Kim A, Carbonella J, Pashankar F. Proteinuria is associated with elevated tricuspid regurgitant jet velocity in children with sickle cell disease. Pediatr Blood Cancer 2012; 58:937-40. [PMID: 21990235 DOI: 10.1002/pbc.23338] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 08/10/2011] [Indexed: 11/05/2022]
Abstract
BACKGROUND Sickle cell disease (SCD) affects multiple organ systems. Complications of SCD such as pulmonary hypertension (PHT) and sickle cell nephropathy (SCN) are associated with an increased mortality. Both PHT and SCN have some common risk factors. In adults, PHT has been found to be associated with albuminuria, a manifestation of SCN. There is no data on this association in children. We conducted a study to determine if elevated pulmonary artery systolic pressures estimated on echocardiogram was associated with proteinuria in children with SCD. METHODS A detailed retrospective chart review was conducted on a cohort of sickle cell patients screened with echocardiograms from June 2005 to July 2010. Patients who had an initial screening echocardiogram and urine analysis within 1 year were included. Longitudinal data from all subsequent echocardiograms and urine analyses were collected. RESULTS Eighty-five patients were included. On initial echocardiograms 32.9% had an elevated tricuspid regurgitant jet velocity (TRV) ≥2.5 m/second. On follow up, in the 28 patients with elevated TRV, 49.27% of all repeat echocardiograms showed persistent elevation. In the 57 patients with normal baseline TRV, 73.6% of all repeat echocardiograms continued to have normal TRV. On initial screening 7.14% of patients with elevated TRV had proteinuria compared to 1.75% without elevated TRV. On follow up, 19.08% of repeat urinalysis had proteinuria in patients with elevated baseline TRV compared to 12.35% in patients with normal baseline TRV (P = 0.04). CONCLUSIONS Elevated TRV ≥ 2.5 m/second is significantly associated with proteinuria on longitudinal follow up in children with SCD.
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Sickle cell disease and venous thromboembolism. Mediterr J Hematol Infect Dis 2011; 3:e2011024. [PMID: 21713075 PMCID: PMC3113276 DOI: 10.4084/mjhid.2011.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Accepted: 05/14/2011] [Indexed: 01/21/2023] Open
Abstract
Hemoglobin S in homozygous state or in combination with one of the structural variants of Hb D-Punjab, Hb O-Arab, Hb C or β-thalassemia mutation results in sickle cell disease (SCD) that is characterized by chronic hemolytic anemia and tissue injury secondary to vasooclusion. A chronic hypercoagulable state in SCD has been established with the increased risk of thromboembolic complications in these patients. The goal of present review is to survey of the literature related to thromboembolic events and genetic risk factors involved in the manifestation of these events in SCD patients with focus on studies from Mediterranean countries. Also, this review covers the pathogenesis of hypercoagulability and alteration in the components of hemostasis system.
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Maître B, Mekontso-Dessap A, Habibi A, Bachir D, Parent F, Godeau B, Galacteros F. Complications pulmonaires des syndromes drépanocytaires majeurs chez l’adulte. Rev Mal Respir 2011; 28:129-37. [DOI: 10.1016/j.rmr.2010.08.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 08/30/2010] [Indexed: 10/18/2022]
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Abstract
Hemoglobinopathies are diseases caused by genetic mutations that result in abnormal, dysfunctional hemoglobin molecules or lower levels of normal hemoglobin molecules. The most common hemoglobinopathies are sickle cell disease (SCD) and the thalassemias. In SCD, an abnormal hemoglobin alters the erythrocyte, causing a chronic hemolytic anemia, which can lead to pulmonary parenchymal damage and impaired vascular function. Pulmonary complications of SCD include the acute chest syndrome (ACS), reactive airways disease, pulmonary hypertension (PH), and pulmonary fibrosis. Episodes of ACS and the development of PH both increase the risk of death in patients with SCD. Both α and β thalassemia are characterized by impaired production of hemoglobin subunits, and severity of disease varies widely. Although screening studies suggest that PH is a common complication for patients with thalassemia, its impact on survival is unknown. Understanding the pathogenesis, diagnostic options, and prevention and treatment strategies for such complications is critical for clinicians who care for these patients. In this review, we discuss the mechanisms and clinical presentation of pulmonary complications associated with hemoglobinopathies, with a focus on recent advances in pathogenesis and treatment.
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Affiliation(s)
- Rekha Vij
- Section of Pulmonary and Critical Care Medicine, University of Chicago Pritzker School of Medicine, Chicago, IL, USA
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Dampier C, Lieff S, LeBeau P, Rhee S, McMurray M, Rogers Z, Smith-Whitley K, Wang W. Health-related quality of life in children with sickle cell disease: a report from the Comprehensive Sickle Cell Centers Clinical Trial Consortium. Pediatr Blood Cancer 2010; 55:485-94. [PMID: 20658620 PMCID: PMC2911637 DOI: 10.1002/pbc.22497] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Pediatric health-related quality of life (HRQOL) questionnaires have been validated in children with sickle cell disease (SCD), but small sample sizes in these studies have limited clinical comparisons. We used the baseline clinical data from the Collaborative Data (C-Data) Project of the Comprehensive Sickle Cell Centers (CSCC) Clinical Trial Consortium to perform a detailed, descriptive study of HRQOL using the PedsQL version 4.0 generic core and fatigue scales. METHODS Retrospective clinical data were obtained via medical record abstraction. Staff-administered health history, psychosocial, and health behavior interviews were completed by a parent or guardian. PedsQL forms were completed separately by the child and a parent/guardian. RESULTS The study enrolled 1,772 subjects (53% boys) with a mean age of 9.6 years (SD 4.7). SS or Sbeta(0) thalassemia occurred in 68% and 32% had SC or Sbeta(+) thalassemia. The occurrences of pain, priapism, avascular necrosis of hips/shoulders (AVN), or asthma were the most common complications/conditions reported. Multiple regression models controlling for hemoglobinopathies, gender, and age suggested that parent reports of physical functioning and sleep/rest fatigue declined in response to pain or AVN, while school functioning scales declined in response to pain or asthma. Sickle pain, and to a lesser extent asthma, negatively influenced child reports on almost all functioning and fatigue scales. CONCLUSIONS While longitudinal studies will be necessary to determine sensitivity to change, the current study suggests the potential utility of several PedsQL HRQOL scales as patient-reported outcome measures for observational or interventional treatment studies of children and adolescents with SCD.
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Affiliation(s)
- Carlton Dampier
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
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Machado RF, Gladwin MT. Pulmonary hypertension in hemolytic disorders: pulmonary vascular disease: the global perspective. Chest 2010; 137:30S-38S. [PMID: 20522578 DOI: 10.1378/chest.09-3057] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The inherited hemoglobin disorders sickle cell disease and thalassemia are the most common monogenetic disorders worldwide. Pulmonary hypertension is one of the leading causes of morbidity and mortality in adult patients with sickle cell disease and thalassemia, and hemolytic disorders are potentially among the most common causes of pulmonary hypertension. The pathogenesis of pulmonary hypertension in hemolytic disorders is likely multifactorial, including hemolysis, impaired nitric oxide (NO) bioavailability, chronic hypoxemia, chronic thromboembolic disease, chronic liver disease, and asplenia. In contrast to patients with traditional forms of pulmonary arterial hypertension, patients with hemolytic disorders have a mild-to-moderate degree of elevation in mean pulmonary pressures, with mild elevations in pulmonary vascular resistance. The hemodynamic etiology of pulmonary hypertension in these patients is multifactorial and includes pulmonary arterial hypertension, pulmonary venous hypertension, and pulmonary hypertension secondary to a hyperdynamic state. Currently, there are limited data on the effects of any specific treatment modality for pulmonary hypertension in patients with hemolytic disorders. It is likely that maximization of treatment of the primary hemoglobinopathy in all patients and treatment with selective pulmonary vasodilators and antiproliferative agents in patients with pulmonary arterial hypertension would be beneficial. However, there is still a major need for large multinational trials of novel therapies for this patient population.
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Affiliation(s)
- Roberto F Machado
- Section of Pulmonary, Critical Care Medicine, Sleep and Allergy, University of Illinois Chicago, Chicago, IL 60612, USA.
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Mokhtar GM, Adly AAM, El Alfy MS, Tawfik LM, Khairy AT. N-terminal natriuretic peptide and ventilation-perfusion lung scan in sickle cell disease and thalassemia patients with pulmonary hypertension. Hemoglobin 2010; 34:78-94. [PMID: 20113292 DOI: 10.3109/03630260903554621] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The aim of this study was to determine the prevalence of pulmonary hypertension (PH) in sickle cell disease and thalassemia patients in relation to clinical and laboratory parameters of hemolysis and hemosidersosis, as well as plasma N-terminal pro-brain natriuretic peptide (NT-pro-BNP). The study also aimed to define the role of thromboembolic pulmonary artery (PA) obstruction in its etiology. Forty sickle cell disease and 30 thalassemia patients [15 beta-thalassemia major (beta-TM) and 15 beta-thalassemia intermedia (beta-TI)] were screened for PH defined as tricuspid regurgitant velocity (TRV) >2.5 m/sec and evaluated for PA obstruction using ventilation-perfusion lung scan (V/Q), together with measurement of their plasma levels of NT-pro-BNP. Patients were prospectively followed up for a mean of 18 +/- 6.1 months. The prevalence of PH was 37.5, 40.0 and 26.7% in sickle cell disease, beta-TI and beta-TM patients, respectively. Pulmonary hypertension patients were older, had longer disease duration, higher serum ferritin, serum lactate dehydrogenase (LDH) and NT-pro-BNP with lower hemoglobin (Hb) levels compared to patients without PH. N-terminal pro-BNP was positively correlated with duration of illness, TRV, LDH, serum ferritin, and negatively correlated with Hb levels. The strongest predictor for TRV was serum ferritin followed by the NT-pro-BNP level. Forty-six-point-seven percent of sickle cell disease patients with PH had either high or intermediate probability V/Q scan results compared to 10% of thalassemic patients with PH who had high probability V/Q scan results. Pulmonary hypertension is highly prevalent in young sickle cell disease and thalassemia patients, where elevated serum ferritin and NT-pro-BNP are the main indicators.
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High levels of placenta growth factor in sickle cell disease promote pulmonary hypertension. Blood 2010; 116:109-12. [PMID: 20335221 DOI: 10.1182/blood-2009-09-244830] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pulmonary hypertension is associated with reduced nitric oxide bioavailability and early mortality in sickle cell disease (SCD). We previously demonstrated that placenta growth factor (PlGF), an angiogenic factor produced by erythroid cells, induces hypoxia-independent expression of the pulmonary vasoconstrictor endothelin-1 in pulmonary endothelial cells. Using a lentivirus vector, we simulated erythroid expression of PlGF in normal mice up to the levels seen in sickle mice. Consequently, endothelin-1 production increased, right ventricle pressures increased, and right ventricle hypertrophy and pulmonary changes occurred in the mice within 8 weeks. These findings were corroborated in 123 patients with SCD, in whom plasma PlGF levels were significantly associated with anemia, endothelin-1, and tricuspid regurgitant velocity; the latter is reflective of peak pulmonary artery pressure. These results illuminate a novel mechanistic pathway linking hemolysis and erythroid hyperplasia to increased PlGF, endothelin-1, and pulmonary hypertension in SCD, and suggest that strategies that block PlGF signaling may be therapeutically beneficial.
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Ivy DD, Feinstein JA, Humpl T, Rosenzweig EB. Non-congenital heart disease associated pediatric pulmonary arterial hypertension. PROGRESS IN PEDIATRIC CARDIOLOGY 2009; 27:13-23. [PMID: 21852894 DOI: 10.1016/j.ppedcard.2009.09.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Recognition of causes of pulmonary hypertension other than congenital heart disease is increasing in children. Diagnosis and treatment of any underlying cause of pulmonary hypertension is crucial for optimal management of pulmonary hypertension. This article discusses the available knowledge regarding several disorders associated with pulmonary hypertension in children: idiopathic pulmonary arterial hypertension (IPAH), pulmonary capillary hemangiomatosis, pulmonary veno-occlusive disease, hemoglobinopathies, hepatopulmonary syndrome, portopulmonary hypertension and HIV. Three classes of drugs have been extensively studied for the treatment of IPAH in adults: prostanoids (epoprostenol, treprostinil, iloprost, beraprost), endothelin receptor antagonists (bosentan, sitaxsentan, ambrisentan), and phosphodiesterase inhibitors (Sildenafil, tadalafil). These medications have been used in treatment of children with pulmonary arterial hypertension, although randomized clinical trial data is lacking. As pulmonary vasodilator therapy in certain diseases may be associated with adverse outcomes, further study of these medications is needed before widespread use is encouraged.
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Affiliation(s)
- D D Ivy
- University of Colorado Denver School of Medicine and The Children's Hospital, United States
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Minniti CP, Sable C, Campbell A, Rana S, Ensing G, Dham N, Onyekwere O, Nouraie M, Kato GJ, Gladwin MT, Castro OL, Gordeuk VR. Elevated tricuspid regurgitant jet velocity in children and adolescents with sickle cell disease: association with hemolysis and hemoglobin oxygen desaturation. Haematologica 2009; 94:340-7. [PMID: 19211639 DOI: 10.3324/haematol.13812] [Citation(s) in RCA: 143] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Elevation of echocardiography-determined tricuspid regurgitant jet velocity predicts high systolic pulmonary artery pressure and early mortality in adults with sickle cell disease. The definition, prevalence and clinical correlates of elevated jet velocity have not been established in pediatric patients. The present study tested the hypotheses that elevated jet velocity affects 10% of pediatric patients, is associated with both hemolysis and hypoxia, and has clinical correlates with acute chest syndrome, stroke, transfusion requirement and abnormal 6-minute walk test results. DESIGN AND METHODS A prospective multicenter study of 310 patients aged 3-20 years old with sickle cell disease under basal conditions and 54 matched controls was conducted. A hemolytic index was generated by principal component analysis of the levels of lactate dehydrogenase, aspartate aminotransferase and bilirubin and reticulocyte count. RESULTS Elevated jet velocity (defined as > or =2.60 m/sec based on the mean+/-2 SD in controls) occurred in 32 patients (11.0%) including one child of 3 years old. After adjustment for hemoglobin concentration, systolic blood pressure and left ventricular diastolic function, a 2 SD increase in the hemolytic index was associated with a 4.5-fold increase in the odds of elevated jet velocity (p=0.009) and oxygen saturation < or =98% with a 3.2-fold increase (p=0.028). Two or more episodes of acute chest syndrome had occurred in 28% of children with elevated jet velocity compared to in 13% of other children (p=0.012), more than ten units of blood had been transfused in 39% versus 18% (p=0.017) and stroke had occurred in 19% versus 11% (p=0.2). The distance walked in 6-minute walk tests did not differ significantly, but oxygen saturation declined during the tests in 68% of children with elevated jet velocity compared to in 32% of other children (p=0.0002). CONCLUSIONS According to a pediatric-specific definition the prevalence of elevated jet velocity in this population of young patients with sickle cell disease was 11%. The study provides evidence for independent associations of elevated jet velocity with hemolysis and oxygen desaturation. Further investigations should address whether elevated jet velocity may indicate future complications and whether early intervention is beneficial.
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Abstract
OBJECTIVES Pulmonary hypertension (PHT) is a life-threatening complication of sickle cell disease that occurs in 20% to 40% of adults. Measurement of maximal tricuspid regurgitant jet velocity (TRV) by echocardiography provides a noninvasive screening tool; TRV values > or =2.5 m/s are correlated with PHT and increased mortality. Our objective was to estimate the prevalence of PHT in our pediatric sickle cell population and its possible association with various clinical and laboratory findings, including obstructive sleep apnea and/or pulmonary dysfunction. STUDY DESIGN Eligible children had measurement of the TRV. Clinical data were collected, including detailed history with a standardized sleep apnea questionnaire; those with suggestive histories had polysomonography. Pulmonary function was assessed using whole body plethysmography. RESULTS Of 48 subjects (79% homozygous sickle cell anemia; median age 12 y; 11 receiving chronic transfusion) enrolled in the study, 4 (8.3%) had TRV >2.5 m/s; all had homozygous sickle cell anemia and 1 was receiving hydroxyurea after 3 years of transfusion for secondary stroke prevention. Subjects with elevated TRV had higher indirect bilirubin levels; we found no association between elevated TRV and obstructive apnea or pulmonary function abnormalities. CONCLUSIONS Elevation of TRV was relatively uncommon in our pediatric patients as compared with prevalence reported in adults and may be associated with increased hemolysis. There was no association with obstructive sleep apnea or abnormal pulmonary function.
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Pashankar FD, Carbonella J, Bazzy-Asaad A, Friedman A. Longitudinal follow up of elevated pulmonary artery pressures in children with sickle cell disease. Br J Haematol 2008; 144:736-41. [PMID: 19055665 DOI: 10.1111/j.1365-2141.2008.07501.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Elevated pulmonary artery pressures (PAP) occur in approximately 30% of children with sickle cell disease. In adults, pulmonary hypertension is significantly associated with mortality. There are no data on the long term significance in children. Nineteen children with SS/Sbeta(0) thalassaemia had elevated PAP, defined as tricuspid regurgitant jet velocity (TRV) > or =2.5 m/s on screening echocardiograms. They were prospectively followed for 23 months (range 19-31 months). Patients with initial TRV > or = 3 or TRV > or = 2.5 m/s on repeat echocardiogram had cardiopulmonary evaluation and were offered treatment with hydroxyurea. Associated conditions like asthma and obstructive sleep apnea were treated. 18/19 patients had follow-up echocardiograms. These showed normalization of TRV in 8 patients. Risk factors associated with persistent elevation were higher TRV on initial echocardiogram (P = 0.01), lower haemoglobin (P = 0.003) and lower oxygen saturation (P = 0.03). Five patients with persistently elevated PAP were treated with hydroxyurea. Mean right ventricular pressure dropped from 40.16 to 29.26 (P = 0.017) after 3-6 months and to 23.6 mmHg (P = 0.002) after 9-12 months on treatment. In conclusion (i) At borderline elevation of TRV there is intrapatient variability and echocardiograms should be repeated for confirmation. (ii) Elevated PAP are reversible in children with early detection and treatment with hydroxyurea.
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Affiliation(s)
- Farzana D Pashankar
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06520-8064, USA.
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Placenta growth factor induces 5-lipoxygenase-activating protein to increase leukotriene formation in sickle cell disease. Blood 2008; 113:1129-38. [PMID: 18945963 DOI: 10.1182/blood-2008-07-169821] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Individuals with sickle cell disease (SCD) have increased inflammation, a high incidence of airway hyperreactivity (AH), and increased circulating leukotrienes (LT). We show that expression of 5-lipoxygenase and 5-lipoxygenase activating protein (FLAP), key catalytic molecules in the LT pathway, were significantly increased in peripheral blood mononuclear cells (MNCs) in patients with SCD, compared with healthy controls. Placenta growth factor (PlGF), elaborated from erythroid cells, activated MNC and THP-1 monocytic cells to induce LT production. PlGF-mediated increased FLAP mRNA expression occurred via activation of phosphoinositide-3 (PI-3) kinase, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, and hypoxia inducible factor-1alpha (HIF-1alpha). HIF-1alpha small interfering RNA (siRNA) reduced PlGF-induced FLAP expression. FLAP promoter-driven luciferase constructs demonstrated that PlGF-mediated luciferase induction was abrogated upon mutation of HIF-1alpha response element (HRE), but not the nuclear factor-kappaB (NF-kappaB) site in the FLAP promoter; a finding confirmed by chromatin immunoprecipitation (ChIP) analysis. PlGF also increased HIF-1alpha binding to the HRE in the FLAP promoter. Therefore, it is likely that the intrinsically elevated levels of PlGF in SCD subjects contribute to increased LT, which in turn, mediate both inflammation and AH. Herein, we identify a mechanism of increased LT in SCD and show HIF-1alpha as a hypoxia-independent target of PlGF. These studies provide new avenues to ameliorate these complications.
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Villavicencio K, Ivy D, Cole L, Nuss R. Symptomatic pulmonary hypertension in a child with sickle cell disease. J Pediatr 2008; 152:879-81. [PMID: 18492535 PMCID: PMC3128440 DOI: 10.1016/j.jpeds.2008.01.042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2007] [Revised: 11/30/2007] [Accepted: 01/30/2008] [Indexed: 11/18/2022]
Abstract
Pulmonary hypertension is a survival-limiting complication in adults with homozygous sickle cell disease (SS), but little is known about the development, course, or best treatment of pulmonary hypertension in children with SS. We report the clinical course and treatment of a child with SS-associated, hemolysis-driven pulmonary hypertension.
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Affiliation(s)
- Karrie Villavicencio
- Department of Cardiology, University of Colorado at Denver Health Sciences Center, Denver, CO, USA
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40
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Wood KC, Hsu LL, Gladwin MT. Sickle cell disease vasculopathy: a state of nitric oxide resistance. Free Radic Biol Med 2008; 44:1506-28. [PMID: 18261470 DOI: 10.1016/j.freeradbiomed.2008.01.008] [Citation(s) in RCA: 156] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2007] [Revised: 11/21/2007] [Accepted: 01/11/2008] [Indexed: 12/31/2022]
Abstract
Sickle cell disease (SCD) is a hereditary hemoglobinopathy characterized by microvascular vaso-occlusion with erythrocytes containing polymerized sickle (S) hemoglobin, erythrocyte hemolysis, vasculopathy, and both acute and chronic multiorgan injury. It is associated with steady state increases in plasma cell-free hemoglobin and overproduction of reactive oxygen species (ROS). Hereditary and acquired hemolytic conditions release into plasma hemoglobin and other erythrocyte components that scavenge endothelium-derived NO and metabolize its precursor arginine, impairing NO homeostasis. Overproduction of ROS, such as superoxide, by enzymatic (xanthine oxidase, NADPH oxidase, uncoupled eNOS) and nonenzymatic pathways (Fenton chemistry), promotes intravascular oxidant stress that can likewise disrupt NO homeostasis. The synergistic bioinactivation of NO by dioxygenation and oxidation reactions with cell-free plasma hemoglobin and ROS, respectively, is discussed as a mechanism for NO resistance in SCD vasculopathy. Human physiological and transgenic animal studies provide experimental evidence of cardiovascular and pulmonary resistance to NO donors and reduced NO bioavailability that is associated with vasoconstriction, decreased blood flow, platelet activation, increased endothelin-1 expression, and end-organ injury. Emerging epidemiological data now suggest that chronic intravascular hemolysis is associated with certain clinical complications: pulmonary hypertension, cutaneous leg ulcerations, priapism, and possibly stroke. New therapeutic strategies to limit intravascular hemolysis and ROS generation and increase NO bioavailability are discussed.
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Affiliation(s)
- Katherine C Wood
- Vascular Medicine Branch, National Heart Lung Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
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41
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Pashankar FD, Carbonella J, Bazzy-Asaad A, Friedman A. Prevalence and risk factors of elevated pulmonary artery pressures in children with sickle cell disease. Pediatrics 2008; 121:777-82. [PMID: 18381543 DOI: 10.1542/peds.2007-0730] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVES The objectives of this study were (1) to determine the prevalence and risk factors of elevated pulmonary artery pressures in children with homozygous SS or Sbeta(0) thalassemia using Doppler echocardiography and (2) to determine a correlation between abnormal transcranial Doppler examinations and elevated pulmonary artery pressures. METHODS Screening echocardiograms were prospectively performed during an annual comprehensive clinic visit on children who were older than 6 years and had homozygous SS or Sbeta(0) thalassemia. Detailed history, examination, and laboratory tests were done, and transcranial Doppler examinations were obtained in children 2 to 14 years of age. Pulmonary hypertension was defined as pulmonary artery systolic pressure of at least 30 mmHg corresponding to a peak tricuspid regurgitant jet velocity of > or = 2.5 m/second. Mild pulmonary hypertension was defined as tricuspid regurgitant jet velocity > or = 2.5 to 2.9 m/second. Moderate pulmonary hypertension was defined as tricuspid regurgitant jet velocity > or = 3 m/second. Patients with pulmonary stenosis or right outflow obstruction were excluded. Characteristics were compared between patients with mild, moderate, and no pulmonary hypertension using 1-way analysis of variance for continuous variable and Fisher's exact test for categorical variables. RESULTS Of the 75 patients who had homozygous SS/Sbeta(0) thalassemia and were older than 6 years, echocardiograms were obtained for 62 (82.6%). Thirty percent (19 of 62) of patients had elevated tricuspid regurgitant jet velocity > or = 2.5 m/second. One third of these patients had tricuspid regurgitant jet velocity > or = 3 m/second. All patients with elevated tricuspid regurgitant jet velocity had SS disease. A high reticulocyte count, low oxygen saturation, and a high platelet count were significantly associated with elevated pulmonary artery pressures. There was no difference in age, gender, history of acute chest syndrome, hydroxyurea therapy, chronic blood transfusion, stroke, hemoglobin, and bilirubin between patients with and without elevated pulmonary artery pressures. A total of 47% patients with elevated tricuspid regurgitant jet velocity and 57% without elevated tricuspid regurgitant jet velocity had screening transcranial Doppler examinations. Transcranial Doppler examinations were normal for all patients. CONCLUSIONS High pulmonary artery pressures do occur in children with sickle cell disease. Screening by echocardiography can lead to early detection and intervention that may potentially reverse this disease process. There was no correlation between elevated pulmonary artery pressures and abnormal transcranial Doppler examination in our study.
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Affiliation(s)
- Farzana D Pashankar
- Department of Pediatrics, Yale University School of Medicine, LMP 2073, 333 Cedar St, PO Box 208064, New Haven, CT 06520-8064, USA.
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van Beers EJ, van Eck-Smit BL, Mac Gillavry MR, van Tuijn CF, van Esser JW, Brandjes DP, Kappers-Klunne MC, Duits AJ, Biemond BJ, Schnog JJB. Large and Medium-Sized Pulmonary Artery Obstruction Does Not Play a Role of Primary Importance in the Etiology of Sickle-Cell Disease-Associated Pulmonary Hypertension. Chest 2008; 133:646-52. [DOI: 10.1378/chest.07-1694] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Aliyu ZY, Kato GJ, Taylor J, Babadoko A, Mamman AI, Gordeuk VR, Gladwin MT. Sickle cell disease and pulmonary hypertension in Africa: a global perspective and review of epidemiology, pathophysiology, and management. Am J Hematol 2008; 83:63-70. [PMID: 17910044 DOI: 10.1002/ajh.21057] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Secondary pulmonary hypertension (PAH) has been shown to have a prevalence of 30% in patients with sickle cell disease (SCD) with mortality rates of 40% at 40 months after diagnosis in the United States. The burden of SCD is highest in sub-Saharan Africa, especially in Nigeria (West Africa), where approximately 6 million people are afflicted. The true global incidence, prevalence, and burden of SCD and its associated end organ complications however remain unknown. Chronic hemolysis represents a prominent mechanistic pathway in the pathogenesis of SCD-associated pulmonary hypertension via a nitric oxide (NO) scavenging and abrogation of NO salutatory effects on vascular function, including smooth muscle relaxation, downregulation of endothelial adhesion molecules and inhibition of platelet activation. Many known infectious risk factors for PAH are also hyperendemic in Africa, including Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome (HIV/AIDS), chronic hepatitis B and C, and possibly malaria. Interactions between these infectious complications and SCD-related hemolysis could yield an even higher prevalence of pulmonary hypertension and compound the existing global health systems challenges in managing SCD. Indeed, our preliminary analysis of African immigrants currently in the United States suggests that pulmonary hypertension represents a significant complication of SCD in the African subcontinent. There is clearly a need to include Africa and other parts of the world with high SCD prevalence in future comprehensive studies on the epidemiology and treatment of end organ complications of an aging SCD population world-wide.
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Affiliation(s)
- Zakari Y Aliyu
- Vascular Medicine Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892-1662, USA.
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44
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Steinberg MH. Clinical trials in sickle cell disease: adopting the combination chemotherapy paradigm. Am J Hematol 2008; 83:1-3. [PMID: 17724701 DOI: 10.1002/ajh.21033] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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45
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Abstract
Developments in the treatment of sickle cell disease (SCD) have not kept pace with advances in understanding the pathophysiology of this haemoglobinopathy. Drugs undergoing preclinical and clinical assessment for the therapy of these globin gene disorders are discussed in this article. Beginning with investigational agents for treatment of SCD as a whole, the discussion proceeds to drugs being developed for specific manifestations or iatrogenic complications. Despite being licensed in the USA, the prototype antisickling agent, hydroxycarbamide, has not attained worldwide clinical use because of concerns about long-term toxicity. The less toxic decitabine, which (as with hydroxycarbamide) increases fetal haemoglobin level, cannot be administered orally; therefore, the search continues for effective and safe antisickling drugs that can be taken orally. The naturally occurring benzaldehyde 5-hydroxymethyl-2-furfural has shown promising antisickling properties in vitro, and when administered to transgenic sickle mice. These effects are surpassed by the new synthetic pyridyl derivatives of benzaldehyde. Studies in humans with SCD are required to assess the clinical efficacy of these benzaldehydes. Niprisan, another antisickling agent with significant clinical efficacy and an attractive safety profile, is undergoing further development. The prospects of antiadhesion therapy in SCD are demonstrated by a recombinant protein containing the Fc fragment of IgG fused to the natural ligand for selectins: the conjugate significantly inhibited blood vessel occlusion in transgenic sickle mice. Whereas the orally administrable iron-chelating agent deferasirox is likely to increasingly take the place of desferioxamine (which can only be given parenterally), effective treatment of priapism in SCD remains a distressing challenge.
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MESH Headings
- Acetamides/pharmacology
- Acetamides/therapeutic use
- Anemia, Sickle Cell/complications
- Anemia, Sickle Cell/drug therapy
- Anemia, Sickle Cell/metabolism
- Anemia, Sickle Cell/therapy
- Animals
- Antihypertensive Agents/therapeutic use
- Antisickling Agents/pharmacology
- Antisickling Agents/therapeutic use
- Benzaldehydes/pharmacology
- Benzaldehydes/therapeutic use
- Benzoates/administration & dosage
- Benzoates/therapeutic use
- Carnitine/therapeutic use
- Cell Adhesion
- Deferasirox
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Etilefrine/therapeutic use
- Female
- Genetic Therapy/methods
- Hematopoietic Stem Cell Transplantation
- Humans
- Hydroxyurea/pharmacology
- Hydroxyurea/therapeutic use
- Hypertension, Pulmonary/drug therapy
- Hypertension, Pulmonary/etiology
- Iron Chelating Agents/administration & dosage
- Iron Chelating Agents/therapeutic use
- Male
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/pharmacology
- Membrane Glycoproteins/therapeutic use
- Potassium Channels, Calcium-Activated/antagonists & inhibitors
- Potassium Channels, Calcium-Activated/metabolism
- Priapism/drug therapy
- Priapism/etiology
- Recombinant Fusion Proteins/pharmacology
- Recombinant Fusion Proteins/therapeutic use
- Triazoles/administration & dosage
- Triazoles/therapeutic use
- Trityl Compounds/pharmacology
- Trityl Compounds/therapeutic use
- Vasoconstrictor Agents/therapeutic use
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Affiliation(s)
- Iheanyi Okpala
- St Thomas' Hospital, University of London, London SE1 7EH, UK.
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46
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Hagar RW, Michlitsch JG, Gardner J, Vichinsky EP, Morris CR. Clinical differences between children and adults with pulmonary hypertension and sickle cell disease. Br J Haematol 2007; 140:104-12. [PMID: 17916102 DOI: 10.1111/j.1365-2141.2007.06822.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Pulmonary hypertension (PHT) is an important co-morbidity in sickle cell disease (SCD). Despite increasing research in adults, the prevalence and implication of this condition in children is unknown. Charts of 362 SCD patients followed at the Children's Hospital & Research Center Oakland were reviewed to determine clinical variables associated with obtaining echocardiographic screening for PHT, clinical associations of PHT, and associated mortality following diagnosis in adults and children with SCD. In this cohort, patients with underlying lung abnormalities or those on chronic transfusions were more likely to have echocardiograms, however the diagnosis of PHT was often unrecognized. A different clinical phenotype for PHT in adults versus children was identified. Associations with PHT for adults included age, renal and lung disease, hepatitis C, chronic transfusions, and a history of acute chest syndrome (ACS), with ACS being protective. Surprisingly, for children, a history of sepsis, along with a history of ACS, or obstructive lung disease were associated with PHT. Survival analysis found significant mortality for PHT, with a hazard ratio of 17.3 (95% confidence interval 4.9-60.4). The divergent clinical spectrum for PHT between adults and children may point to different age-specific mechanisms or biological expression of PHT.
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Affiliation(s)
- R Ward Hagar
- Hematology/Oncology, Children's Hospital & Research Center Oakland, Oakland, CA 94609, USA.
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47
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Frenette PS, Atweh GF. Sickle cell disease: old discoveries, new concepts, and future promise. J Clin Invest 2007; 117:850-8. [PMID: 17404610 PMCID: PMC1838946 DOI: 10.1172/jci30920] [Citation(s) in RCA: 218] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The discovery of the molecular basis of sickle cell disease was an important landmark in molecular medicine. The modern tools of molecular and cellular biology have refined our understanding of its pathophysiology and facilitated the development of new therapies. In this review, we discuss some of the important advances in this field and the impediments that limit the impact of these advances.
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Affiliation(s)
- Paul S Frenette
- Division of Hematology/Oncology, Mount Sinai School of Medicine, New York, New York 10029, USA
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48
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Rivera A. Reduced sickle erythrocyte dehydration in vivo by endothelin-1 receptor antagonists. Am J Physiol Cell Physiol 2007; 293:C960-6. [PMID: 17494628 DOI: 10.1152/ajpcell.00530.2006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Elevated plasma levels of cytokines such as endothelin-1 (ET-1) have been shown to be associated with sickle cell disease (SCD). However, the role of ET-1 in the pathophysiology of SCD is not entirely clear. I now show that treatment of SAD mice, a transgenic mouse model of SCD, with BQ-788 (0.33 mg.kg(-1).day(-1) intraperitoneally for 14 days), an ET-1 receptor B (ET(B)) antagonist, induced a significant decrease in Gardos channel activity (1.7 +/- 0.1 to 1.0 +/- 0.4 mmol.10(13) cell(-1).h(-1), n = 3, P = 0.019) and reduced the erythrocyte density profile by decreasing the mean density (D(50); n = 4, P = 0.012). These effects were not observed in mice treated with BQ-123, an ET-1 receptor A (ET(A)) antagonist. A mixture of both antagonists induced a similar change in density profile as with BQ-788 alone that was associated with an increase in mean cellular volume and a decrease in corpuscular hemoglobin concentration mean. I also observed in vitro effects of ET-1 on human sickle erythrocyte dehydration that was blocked by BQ-788 and a mixture of ET(B)/ET(A) antagonists but not by ET(A) antagonist alone. These results show that erythrocyte hydration status in vivo is mediated via activation of the ET(B) receptor, leading to Gardos channel modulation in SCD.
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Affiliation(s)
- Alicia Rivera
- Dept. of Laboratory Medicine, Bader 7, Children's Hospital Boston, 300 Longwood Ave., Boston, MA 02115, USA.
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49
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Abstract
The therapy of pulmonary hypertension has evolved rapidly in the last 10 years from the use of non-selective vasodilators to drugs that specifically target pulmonary vasodilation, endothelial function, and vascular remodeling. Sildenafil is a phosphodiesterase type 5 inhibitor that has an expanding role in the treatment of pulmonary hypertension. Case series and small studies, as well as the first large randomized controlled trial, have demonstrated the safety and efficacy of sildenafil in improving mean pulmonary artery pressure, pulmonary vascular resistance, cardiac index, and exercise tolerance in pulmonary arterial hypertension. It may be useful in adults, children, and neonates after cardiac surgery, with left heart failure, in fibrotic pulmonary disease, high altitude exposure, and thromboembolic disease, and in combination with other therapies for pulmonary hypertension, such as inhaled iloprost. The oral formulation and favorable adverse effect profile make sildenafil an attractive alternative in the treatment of selected patients with pulmonary hypertension.
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Affiliation(s)
- Christopher F Barnett
- Critical Care Medicine Department, Clinical Center, National Institutes of HealthBethesda, MD, USA
- Vascular Medicine Branch, National Heart Lung and Blood Institute, National Institutes of HealthBethesda, MD, USA
| | - Roberto F Machado
- Critical Care Medicine Department, Clinical Center, National Institutes of HealthBethesda, MD, USA
- Vascular Medicine Branch, National Heart Lung and Blood Institute, National Institutes of HealthBethesda, MD, USA
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Isma'eel H, Arnaout MS, Shamseddeen W, Mahfouz R, Zeineh N, Jradi O, Taher A. Screening for inherited thrombophilia might be warranted among Eastern Mediterranean sickle-beta-0 thalassemia patients. J Thromb Thrombolysis 2006; 22:121-3. [PMID: 17008978 DOI: 10.1007/s11239-006-8953-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND The role of genetic thrombophilia in the development of both micro and macro vascular complications in patients with hemoglobinopathies (Sickle cell disease and thalassemia) have been investigated with some studies negating its role while others suggesting it. Lebanon is known to harbor sickle cell disease, thalassemia and sickle beta-thalassemia hemoglobinopathy patients along with a documented high prevalence of genetic thrombophilia mutations. METHODS Twelve sickle beta-0-thalassemia patients with no pervious history of thrombotic events were selected. These patients underwent a physical examination with history, echo Doppler, along with blood withdrawal for complete blood count and PCR analysis of a sample of DNA for Factor V Leiden G1691A, Factor II G20210A, and MTHFR C677T. Results were compared to a historical control of 50 Lebanese controls and 50 LebaneseThalassemia Intermedia (TI) patients. RESULTS The results showed that 42%, 59%, and 8% of patients carried heterozygous Factor V Leiden, abnormal (homozygous & heterozygous) MTHFR, and heterozygous Factor II mutations respectively. The sickle-thalassemia patients were 5.24 and 4.39 times more likely to have Factor V Leiden as compared to the normal controls and TI patients respectively (p < 0.05). DISCUSSION The increased prevalence of more than one prothrombotic genetic mutation among the group indicates a probable clustering phenomenon, unknown to us to which the high consanguinity rate (77%) may have contributed. The role of the specific MTHFR and Factor V Leiden double heterozygous combination in incidence, recurrence, and guidance of duration of therapy in VTE is not well defined in the literature despite the recognized higher risk of thrombosis among this patient population. Our findings suggest that genetic thrombophilia workup is necessary in patients with sickle-beta zero thalassemia presenting with thrombotic events and studies that include a larger number of patients are necessary in order to define specific guidelines.
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