[Guidelines for management of adult sickle cell disease]

Preventive treatment of unruptured intracranial aneurysms in adult patients with sickle cell anemia: A cohort study

BACKGROUND AND PURPOSE

Intracranial aneurysms are frequent in patients with sickle cell anemia, while subarachnoid hemorrhage is a major cause of death and disability in young adult patients. Several characteristics, such as younger age and smaller size at rupture, may incline therapeutic decision towards exclusion treatments. Clinical guidelines on treatment of unruptured intracranial aneurysms in this population are still missing. We aimed to assess the safety and efficacy of the treatment of unruptured intracranial aneurysm in patients with sickle cell anemia, using an adapted hematological preparation regimen.

PATIENTS AND METHODS

Adult patients with sickle cell anemia and treated unruptured aneurysms by endovascular therapy or neurosurgery were included in this retrospective cohort study. Treatment decision was reached after multi-disciplinary assessment. A pre-operative blood transfusion protocol was undertaken targeting a HbS below 30%. Demographic data, hematological preparation parameters and clinical and radiological outcomes were documented.

RESULTS AND CONCLUSIONS

Twenty-five procedures were performed in 18 patients encompassing 19 aneurysms treated by embolization and 6 by surgery. Median age at treatment was 34 years-old and median aneurysm dome size was 4.4 mm. Immediate aneurysm exclusion rate was 85.7% after endovascular therapy and 100% after neurosurgery. Median follow-up was 6 months, with all patients being asymptomatic at last follow-up. Two transitory ischemic neurological deficits, as well as four cases of iodine-induced encephalopathy were identified after embolization. No complication occurred after surgery. Endovascular therapy by coiling and neurosurgical treatment of unruptured intracranial aneurysms appears to be safe in patients with sickle cell anemia and should be considered given the specific hemorrhagic risk observed in this population. A rigorous hematological preparation, associated with a dedicated peri‑operative protocol and an adequate therapeutic strategy are essential prerequisites.

Prise en charge d’un patient drépanocytaire aux urgences

La drépanocytose est aujourd’hui la première maladie génétique en France avec environ 30 000 patients adultes. Une mutation ponctuelle sur le chromosome 11 conduit à la production d’une hémoglobine pathologique qui polymérise sous l’effet de facteurs endo-ou exogènes induisant la falciformation des globules rouges à l’origine d’une vasoocclusion artérielle dont une des conséquences est l’oblitération des vaisseaux à destinée osseuse. Les infarctus osseux sont particulièrement douloureux, conduisant les patients aux urgences où l’enjeu est de soulager rapidement les douleurs par l’utilisation de morphine principalement par analgésie autocontrôlée après titration morphinique. Le risque majeur au cours de ces crises vaso-occlusives (CVO) est l’apparition d’un syndrome thoracique aigu (STA) pouvant mettre en jeu le pronostic vital du patient. La spirométrie incitative est un moyen préventif du STA important à instituer dès les urgences. Une antibiothérapie sera mise en place en cas de fièvre chez ces patients aspléniques à risque d’infections à germes encapsulés notamment par le pneumocoque. L’échange transfusionnel est une des pierres angulaires du traitement des CVO ou du STA mais le risque d’accident hémolytique aigu post transfusionnel doit en limiter l’usage à des situations mettant en jeu le pronostic vital ou fonctionnel d’organe. Plusieurs scores clinicobiologiques permettent de décider de l’utilité d’un angioscanner thoracique au cours du STA à la recherche d’une embolie pulmonaire ou pour décider de la pertinence d’une sortie vers une hospitalisation à domicile (Programme DREPADOM). L’utilisation de la morphine en dehors de l’hôpital de façon prolongée doit être prudente en raison du risque d’addiction.

[Pregnancy planning and follow-up of a pregnant woman with sickle cell disease]

Pregnancy is a high-risk situation in sickle cell patients, both for the mother and the foetus. It considerably increases the risk of an acute complication (vaso-occlusive crisis, acute chest syndrome, infection, thrombosis) of sickle cell disease. In addition, this condition increases the risk of placental vascular complications (in utero growth retardation, pre-eclampsia, retroplacental haematoma and in utero foetal death).

Nationwide retrospective study of critically ill adults with sickle cell disease in France

Little is known about patients with sickle cell disease (SCD) who require intensive care unit (ICU) admission. The goals of this study were to assess outcomes in patients admitted to the ICU for acute complications of SCD and to identify factors associated with adverse outcomes. This multicenter retrospective study included consecutive adults with SCD admitted to one of 17 participating ICUs. An adverse outcome was defined as death or a need for life-sustaining therapies (non-invasive or invasive ventilation, vasoactive drugs, renal replacement therapy, and/or extracorporeal membrane oxygenation). Factors associated with adverse outcomes were identified by mixed multivariable logistic regression. We included 488 patients admitted in 2015-2017. The main reasons for ICU admission were acute chest syndrome (47.5%) and severely painful vaso-occlusive event (21.3%). Sixteen (3.3%) patients died in the ICU, mainly of multi-organ failure following a painful vaso-occlusive event or sepsis. An adverse outcome occurred in 81 (16.6%; 95% confidence interval [95% CI], 13.3%-19.9%) patients. Independent factors associated with adverse outcomes were low mean arterial blood pressure (adjusted odds ratio [aOR], 0.98; 95% CI 0.95-0.99; p = 0.027), faster respiratory rate (aOR, 1.09; 95% CI 1.05-1.14; p < 0.0001), higher haemoglobin level (aOR, 1.22; 95% CI 1.01-1.48; p = 0.038), impaired creatinine clearance at ICU admission (aOR, 0.98; 95% CI 0.97-0.98; p < 0.0001), and red blood cell exchange before ICU admission (aOR, 5.16; 95% CI 1.16-22.94; p = 0.031). Patients with SCD have a substantial risk of adverse outcomes if they require ICU admission. Early ICU admission should be encouraged in patients who develop abnormal physiological parameters.

Homozygous sickle cell disease related mortality in Senegal (2011–2020)

Homozygous sickle cell disease (HSCD) is characterized by multiorgan morbidity and an increased risk of early death. We aim to describe the mortality rate, causes, and risk factors of death in HSCD between 2011 and 2020. We conducted a retrospective study with a duration of 10 years in the cohort of 2348 HSCD patients. The mortality rate was determined by reporting the number of deaths to the total number of patients followed in the year. Sociodemographic, clinical, biological data and causes of death were studied. Death risk factors were determined by a bivariate analysis comparing deceased and living HSCD patients. The mean age of death was 26 years (3–52). The sex ratio was 1.2. The mortality rate was 2.76%. The death rate was high in 2011 (3.2%) and low in 2020 (0.17%). We observed a significant reduction of mortality of 94.6%. Most of the common causes of death were acute anemia (40%), acute chest syndrome (24.6%), and infections (20%). Risk factors of death were age, vaso‐occlusive crises ≥3, acute chest syndrome, blood transfusion, and chronic complications. Mortality among HSCD has significantly decreased over the past 10 years in Senegal, and the main causes of death were acute anemia, acute chest syndrome, and infections.

Lentiviral and genome-editing strategies for the treatment of β-hemoglobinopathies

β-Thalassemia and sickle cell disease (SCD) are the most prevalent monogenic diseases. These disorders are caused by quantitative or qualitative defects in the production of adult hemoglobin. Gene therapy is a potential treatment option for patients lacking an allogenic compatible hematopoietic stem cell (HSC) donor. New-generation lentiviral vectors (LVs) carrying a β-globin-like gene have revolutionized this field by allowing effective HSC transduction, with no evidence of genotoxicity to date. Several clinical trials with different types of vector are underway worldwide; the initial results are encouraging with regard to the sustained production of therapeutic hemoglobin, improved biological parameters, a lower transfusion requirement, and better quality of life. Long-term follow-up studies will confirm the safety of LV-based gene therapy. The optimization of patient conditioning, HSC harvesting, and HSC transduction has further improved the therapeutic potential of this approach. Novel LV-based strategies for reactivating endogenous fetal hemoglobin (HbF) are also promising, because elevated HbF levels can reduce the severity of both β-thalassemia and SCD. Lastly, genome-editing approaches designed to correct the disease-causing mutation or reactivate HbF are currently under investigation. Here, we discuss the clinical outcomes of current LV-based gene addition trials and the promising advantages of novel alternative therapeutic strategies.

[Emergency treatment of sickle cell diseases in the Blood Diseases Department at the Koutoukou Maga National Teaching Hospital, Cotonou, Benin]

Introduction

L'évolution de la drépanocytose est marquée par la survenue de complications aigues dont certaines constituent de véritables urgences pouvant mettre en jeu le pronostic vital ou fonctionnel. Notre travail avait pour objectif d'étudier la fréquence et l'évolution des urgences drépanocytaires dans le Service des Maladies du Sang (SMAS) du Centre National Hospitalier Universitaire-Hubert Koutoukou Maga (CNHU-HKM) de Cotonou.

Méthodes

Nous avons mené une étude rétrospective et descriptive de janvier 2014 à décembre 2015 et portant sur l'ensemble des patients hospitalisés pour une urgence drépanocytaire. Nous avons exclu les patients hospitalisés pour des complications drépanocytaires chroniques.

Résultats

Deux cent quatre (204) urgences drépanocytaires pour un nombre total de 813 hospitalisations ont été enregistrés (prévalence de 25%). L'âge moyen des patients était de 24,2 ans. La tranche d'âge la plus représentée était celle de 20-30 ans (45,6%). Le sexe masculin prédominait à 60,8%. Les élèves/étudiants étaient les plus représentés à 55,9%. La douleur aigue était le motif principal d'hospitalisation à 63,7%. L'homozygotie SS était majoritairement représentée à 72,1%. Les complications vaso-occlusives ostéo-articulaires prédominaient à 70,1%. Les complications infectieuses documentées étaient dominées par le paludisme (27,5%). La décompensation anémique était notée à 30,4%. Sur le plan thérapeutique, l'hydratation a été utilisée à 85,3%. La durée moyenne de séjour était de 5,4 jours. L'évolution a été favorable dans 96,5% des cas. La létalité était de 2,5%.

Conclusion

Les urgences drépanocytaires sont fréquentes. Elles nécessitent un diagnostic rapide et une prise en charge précoce et efficace. La formation continue du personnel médical à la prise en charge des urgences drépanocytaires s'avère nécessaire pour réduire leur mortalité.

Plerixafor enables safe, rapid, efficient mobilization of hematopoietic stem cells in sickle cell disease patients after exchange transfusion

Sickle cell disease is characterized by chronic anemia and vaso-occlusive crises, which eventually lead to multi-organ damage and premature death. Hematopoietic stem cell transplantation is the only curative treatment but it is limited by toxicity and poor availability of HLA-compatible donors. A gene therapy approach based on the autologous transplantation of lentiviral-corrected hematopoietic stem and progenitor cells was shown to be efficacious in one patient. However, alterations of the bone marrow environment and properties of the red blood cells hamper the harvesting and immunoselection of patients' stem cells from bone marrow. The use of Filgrastim to mobilize large numbers of hematopoietic stem and progenitor cells into the circulation has been associated with severe adverse events in sickle cell patients. Thus, broader application of the gene therapy approach requires the development of alternative mobilization methods. We set up a phase I/II clinical trial whose primary objective was to assess the safety of a single injection of Plerixafor in sickle cell patients undergoing red blood cell exchange to decrease the hemoglobin S level to below 30%. The secondary objective was to measure the efficiency of mobilization and isolation of hematopoietic stem and progenitor cells. No adverse events were observed. Large numbers of CD34⁺ cells were mobilized extremely quickly. Importantly, the mobilized cells contained high numbers of hematopoietic stem cells, expressed high levels of stemness genes, and engrafted very efficiently in immunodeficient mice. Thus, Plerixafor can be safely used to mobilize hematopoietic stem cells in sickle cell patients; this finding opens up new avenues for treatment approaches based on gene addition and genome editing. Clinicaltrials.gov identifier: NCT02212535.

RETRACTED: Delayed Hemolytic Transfusion Reaction and Hyperhemolysis Syndrome without Detectable Alloantibodies or Autoantibodies in a Patient with Sickle Cell Disease: A Fatal Case Report and Literature Review

L'éditeur a le regret de vous informer que cet article a déjà été publié dans: Journal of Blood Disorders & Transfusion, 2017, 8:4. DOI: 10.4172/2155-9864.1000388. Cette seconde publication faite par erreur a été retirée.

Delayed hemolytic transfusion reaction in adult sickle-cell disease: presentations, outcomes, and treatments of 99 referral center episodes

Delayed hemolytic transfusion reaction (DHTR) is one of the most feared complications of sickle-cell disease (SCD). We retrospectively analyzed the clinical and biological features, treatments and outcomes of 99 DHTRs occurring in 69 referral center patients over 12 years. The first clinical signs appeared a median of 9.4 [IQR, 3-22] days after the triggering transfusion (TT). The most frequent DHTR-related clinical manifestation was dark urine/hemoglobinuria (94%). Most patients (89%) had a painful vaso-occlusive crisis and 50% developed a secondary acute chest syndrome (ACS). The median [IQR] hemoglobin-concentration nadir was 5.5 [4.5-6.3] g/dL and LDH peak was 1335 [798-2086] IU/L. Overall mortality was 6%. None of the patients had been receiving chronic transfusions. Among these DHTRs, 61% were developed in previously immunized patients, 28% in patients with prior DHTR. Among Abs detected after the TT in 62% of the episodes, half are classically considered potentially harmful. No association could be established between clinical severity and immunohematological profile and/or the type and specificity of Abs detected after the TT. Management consisted of supportive care alone (53%) or with adjunctive measures (47%), including recombinant erythropoietin and sometimes rituximab and/or immunosuppressants. Additional transfusions were either ineffective or worsened hemolysis. In some cases, severe intravascular hemolysis can be likely responsible for the vascular reaction and high rates of ACS, pulmonary hypertension and (multi)organ failure. In conclusion, clinicians and patients must recognize early DHTR signs to avoid additional transfusions. For patients with a history of RBC immunization or DHTR, transfusion indications should be restricted. Am. J. Hematol. 91:989-994, 2016. © 2016 Wiley Periodicals, Inc.

Score Predicting Acute Chest Syndrome During Vaso-occlusive Crises in Adult Sickle-cell Disease Patients

Background

Vaso-occlusive crisis (VOC), hallmark of sickle-cell disease (SCD), is the first cause of patients' Emergency-Room admissions and hospitalizations. Acute chest syndrome (ACS), a life-threatening complication, can occur during VOC, be fatal and prolong hospitalization. No predictive factor identifies VOC patients who will develop secondary ACS.

Methods

This prospective, monocenter, observational study on SS/S-β₀thalassemia SCD adults aimed to identify parameters predicting ACS at Emergency-Department arrival. The primary endpoint was ACS onset within 15 days of admission. Secondary endpoints were hospitalization duration, morphine consumption, pain evaluation, blood transfusion(s) (BT(s)), requiring intensive care and mortality.

Findings

Among 250 VOCs included, 247 were analyzed. Forty-four (17.8%) ACSs occurred within 15 (median [IQR] 3 [2, 3]) days post-admission based on auscultation abnormalities; missing chest radiographs excluded three patients. Comparing ACS to VOC, respectively, median hospital stay was longer 9 [7–11] vs 4 [3–7] days (p < 0.0001), 7/41 (17%) vs 1/203 (0.5%) required intensive care (p < 0.0001), and 20/41 (48.7%) vs 6/203 (3%) required BTs (p < 0.0001). No patient died. The multivariate model retained reticulocyte and leukocyte counts, and spine and/or pelvis pain as being independently associated with ACS; the resulting ACS-predictive score's area under the ROC was 0.840 [95% CI 0.780–0.900], 98.8% negative-predictive value and 39.5% positive-predictive value for the real ACS incidence.

Interpretation

The ACS-predictive score is simple, easily applied and could change VOC management and therapeutic perspectives. Assessed ACS risk could lead to earlier discharges or close monitoring and rapid medical intensification to prevent ACS.

•

Acute chest syndrome is a threatening complication.

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Acute chest syndrome often occurs during a vaso occlusive crisis.

•

Our study provides a predictive score of acute chest syndrome.

[Delayed haemolytic transfusion reaction: About 3 patients with sickle cell disease]

INTRODUCTION

The use of a red blood cell transfusion in a patient with major sickle cell disease is sometimes necessary. The occurrence of delayed haemolytic transfusion reaction is a rare but potentially serious complication. This event can occur at any age. It is probably under diagnosed due to the difficulty in diagnosis with few specific signs.

CASE REPORTS

We describe in this article the clinical, biological, and hazards of therapeutic management of three cases of delayed haemolytic transfusion reaction in sickle cell disease patients. The high performance chromatography, which evaluates the percentage of HbA1, is the biological investigation used to establish the diagnosis of this event. The pathophysiology of this event remains still poorly understood. Several treatments have been used during this event. However, the therapeutic management remains controversial.

CONCLUSION

Transfusion in any patient likely to suffer from delayed haemolytic transfusion reaction is not recommended because of the risk of worsening this reaction. Prevention of recurrence is essential.

[Acute respiratory distress syndrome complicating an acute chest syndrome: potential benefit of early combination of exchange transfusion and prone positioning]

We report the case of an 8-year-old sickle cell anemia child admitted for acute respiratory failure complicating acute chest syndrome. Because of threatening respiratory failure, tracheal intubation was performed immediately after ICU admission. The patient met the criteria for ARDS with a PaO2/FiO2 ratio of 94mmHg. An exchange transfusion was performed immediately after admission. HbS fraction failed from 69 % to 30 %. Fluid resuscitation with crystalloids and continuous norepinephrine infusion was needed because of arterial hypotension. Due to persistent severe hypoxemia with PaO2/FiO2 ratio below 100, the patient was placed in prone positioning 16hours after admission, for a total duration of 14hours. A second 12-hour session of prone positioning was performed 41h after admission and PaO2/FiO2 ratio reached 300mmHg after. Treatment also included transfusion of two red-cell pack on day 1 and 2 after admission in order to maintain hemoglobin level above 8g/dL, and a daily folic acid supplementation. The control of hyperthermia was achieved by a systematic parenteral administration of paracetamol. Cefotaxime and erythromycine were continued until day 7 despite the negative results of all bacteriological samples. The outcome was favorable from day 3 and the patient met the criteria for extubation on day 5. A first attempt of extubation was performed on day 5, but re-intubation was required because of laryngeal edema. Steroids were given for 48h and the patient was successfully extubated on day 7. She was discharged from the ICU on day 8, and from the hospital on day 12. We discuss the various treatments available for the management of acute chest syndrome and their actual relevance in acute respiratory distress syndrome in the absence of strong evidence-based guidelines in pediatric ARDS.

[Tetanus complicated with sepsis on major haemoglobinopathy]

Rapporter un cas de tétanos compliqué de septicémie chez un enfant souffrant d'une hémoglobinopathie majeure. Enfant de 9 ans drépanocytaire (SC), non vacciné contre le tétanos, a été admis au CHU YO pour raideur de la nuque, difficulté à l'ouverture de la bouche et hyperthermie. L'examen à son admission notait un syndrome infectieux avec une hyperthermie (température à 39°1C), Pouls = 100/mn, Fréquence cardiaque = 100batt/mn, fréquence respiratoire = 30cycles/mn, poids =22Kg, un trismus, une contracture des muscles para vertébraux, des paroxysmes toniques à la palpation (stade II de Mollaret), un syndrome méningé. L'examen n'avait pas retrouvé une porte d'entrée. La ponction lombaire avait ramené un liquide céphalo rachidien clair; l'hémogramme avait montré une hyperleucocytose à 10 200/mm³, et l'hémoculture a permis d'isoler Staphylococcus aureus. Sous antibiothérapie et sous sédatifs, l’évolution a été favorable. Les porteurs d'hémoglobinopathie majeure sont plus exposés aux infections. La physiopathologie de ces infections s'explique par l'immunodépression et les troubles de la phagocytose. Un dépistage précoce de ces hémoglobinopathies, un bon suivi et une bonne couverture vaccinale des enfants drépanocytaires sont essentiels pour prévenir le tétanos et ses complications.

Genomic analyses of RH alleles to improve transfusion therapy in patients with sickle cell disease

BACKGROUND

Red cell (RBC) blood group alloimmunization remains a major problem in transfusion medicine. Patients with sickle cell disease (SCD) are at particularly high risk for developing alloantibodies to RBC antigens compared to other multiply transfused patient populations. Hemagglutination is the classical method used to test for blood group antigens, but depending on the typing methods and reagents used may result in discrepancies that preclude interpretation based on serologic reactivity alone. Molecular methods, including customized DNA microarrays, are increasingly used to complement serologic methods in predicting blood type. The purpose of this study was to determine the diversity and frequency of RH alleles in African Americans and to assess the performance of a DNA microarray for RH allele determination.

MATERIAL AND METHODS

Two sets of samples were tested: (i) individuals with known variant Rh types and (ii) randomly selected African American donors and patients with SCD. Standard hemagglutination tests were used to establish the Rh phenotype, and cDNA- and gDNA-based analyses (sequencing, PCR-RFLP, and customized RHD and RHCE microarrays were used to predict the genotype).

RESULTS

In a total of 829 samples (1658 alleles), 72 different alleles (40 RHD and 32 RHCE) were identified, 22 of which are novel. DNA microarrays detected all nucleotides probed, allowing for characterization of over 900 alleles.

CONCLUSIONS

High-throughput DNA testing platforms provide a means to test a relatively large number of donors and potentially prevent immunization by changing the way antigen-negative blood is provided to patients. Because of the high RH allelic diversity found in the African American population, determination of an accurate Rh phenotype often requires DNA testing, in conjunction with serologic testing. Allele-specific microarrays offer a means to perform high-throughput donor Rh typing and serve as a valuable adjunct to serologic methods to predict Rh type. Because DNA microarrays test for only a fixed panel of allelic polymorphisms and cannot determine haplotype phase, alternative methods such as Next Generation Sequencing hold the greatest potential to accurately characterize blood group phenotypes and ameliorate the clinical course of multiply-transfused patients with sickle cell disease.

Lung imaging during acute chest syndrome in sickle cell disease: computed tomography patterns and diagnostic accuracy of bedside chest radiograph

INTRODUCTION

The lung computed tomography (CT) features of acute chest syndrome (ACS) in sickle cell disease patients is not well described, and the diagnostic performance of bedside chest radiograph (CR) has not been tested. Our objectives were to describe CT features of ACS and evaluate the reproducibility and diagnostic performance of bedside CR.

METHODS

We screened 127 consecutive patients during 166 ACS episodes and 145 CT scans (in 118 consecutive patients) were included in the study.

RESULTS

Among the 145 CT scans, 139 (96%) exhibited a new pulmonary opacity and 84 (58%) exhibited at least one complete lung segment consolidation. Consolidations were predominant as compared with ground-glass opacities and atelectasis. Lung parenchyma was increasingly consolidated from apex to base; the right and left inferior lobes were almost always involved in patients with a new complete lung segment consolidation on CT scan (98% and 95% of cases, respectively). Patients with a new complete lung segment consolidation on CT scan had a more severe presentation and course as compared with others. The sensitivity of bedside CR for the diagnosis of ACS using CT as a reference was good (>85%), whereas the specificity was weak (<60%).

CONCLUSIONS

ACS more frequently presented on CT as a consolidation pattern, predominating in lung bases. The reproducibility and diagnostic capacity of bedside CR were far from perfect. These findings may help improve the bedside imaging diagnosis of ACS.

[Study of the satisfaction of the quantitative and qualitative needs of labile blood products' recipients in non self-sufficient transfusion area]

This retrospective study over 4 years, in a non-self-sufficient transfusion region, analyses the qualitative and quantitative needs of recipients of blood components in the phenotypic characteristics red cell specific. If the quantitative needs were still covered with the national solidarity, is not less that a qualitative improvement of supply remains to achieve and requires a collective effort of each of the links in the regional transfusion chain.

Transfusion practices in the management of sickle cell disease: a survey of Florida hematologists/oncologists

The purpose of this study was to characterize transfusion practices in the management of sickle cell disease and to identify factors attributing to differences in prescribing practices among Florida hematologists/oncologists. A cross-sectional study was performed in 2005-2006 utilizing a mail survey. The survey instrument addressed practice characteristics, sickle cell patient populations, transfusion settings, indications and techniques, red blood cell phenotype specifications/modifications, use of practice guidelines, and educational resource utilization. One hundred fifty two physicians (75% adult-oriented, 25% pediatric) completed the survey. Non-academic practice settings (78 %) were the primary location. Pediatric practices had a larger percentage of patients with overt strokes, and receiving hydroxyurea therapy than adult-oriented practices. The majority of survey respondents did not request limited phenotypically matched red blood cells on a routine basis. The majority of pediatric practices (60%) had individually defined transfusion practice guidelines in contrast to 8% of adult-oriented practices. There were statistically significant differences for pediatric and adult-oriented practices in managing certain acute and chronic transfusion indications. Analysis of clinical vignette data revealed variation among hematologists/oncologists in the transfusion management of common clinical scenarios. The study underscores the need for the development and dissemination of comprehensive sickle cell transfusion guidelines and protocols.

Risk factors and impact of orthopaedic monitoring on the outcome of avascular necrosis of the femoral head in adults with sickle cell disease: 215 patients case study with control group

INTRODUCTION

Sickle cell disease is a public health problem. The WHO has recommended that global management be implemented to reduce mortality and morbidity. Since no comprehensive care programme for bone and joint complications exists, the Caribbean Sickle Cell Disease Center added orthopaedic consultation to screen for and monitor these complications in 1992.

HYPOTHESIS

Comprehensive medical and surgical care of patients with sickle cell disease will reduce the complications and disability associated with this disease.

POPULATIONS AND METHODS

Two populations were compared to evaluate the impact of comprehensive disease management on the occurrence of avascular necrosis (AVN) of the femoral head (femoral head AVN). The case-control series, [E-1994], included 115 patients (58 SS and 57 S) without orthopaedic monitoring and was evaluated retrospectively. The other patient series, [E-2008], included 215 patients (94 SS and 121 SC) with systematic orthopaedic care and was followed prospectively. Age, gender, duration of follow-up, haemoglobin levels, genotype, pain before treatment, associated humerus AVN and leg ulcers were analysed.

RESULTS

Femoral head AVN occurred in young adult patients (35.3 ± 4 years for [E-1994] and 29 ± 3.4 years for [E-2008]). Only elevated haemoglobin levels were associated with the occurrence of femoral head AVN, which suggests that increased blood viscosity contributes to the condition ([E-1994], P<0.0001; [E-2008], P=0.001). Treatment in [E-2008] patients reduced the number of femoral head AVN cases from 36.5% in [E-1994] to 14.4% in [E-2008] (P<0.0001).

DISCUSSION

The prevention and management of femoral head AVN must include medical treatment of the disease to reduce the occurrence of painful vaso-occlusive crises, which are known to trigger femoral head AVN. The effectiveness of this programme hinged on identifying risk factors and using simple approaches (hydration, pain medication, rest and crutches) to manage painful joint crises before femoral head AVN appeared. These approaches could be implemented in disadvantaged countries where sickle cell disease is prevalent.

CONCLUSION

By knowing the risk factors, symptomatic patients who are at risk for femoral head AVN can be identified and additional evaluations can be performed early on in cases of hip pain.

[Hyperuricemia in sickle cell disease in France]

PURPOSE

Hyperuricemia has been reported to be a common feature of sickle cell disease occurring between 32 to 41% of the patients, in studies conducted during the 1970's. Since then, this notion has been rarely challenged. The objective of this study was to assess the prevalence of hyperuricemia and gout in adult patients with sickle cell disease in France.

METHODS

Between May 2007 and March 2009, serum and urinary urate concentration, creatininemia and hemogram were prospectively assessed in all consecutive sickle cell patients, followed in our sickle cell disease centre. All subjects were in a clinically steady state. Clinical acute gout history was also recorded.

RESULTS

Sixty-five patients (mean age 31±10.3 years) were investigated. Mean uric acid serum level was 281.6±74μmol/L. Hyperuricemia was evidenced in six patients only (9.2%) (95% IC: 3.5-19.0). None of the patient had a medical history of acute gout. Patients in the higher serum uric acid tertile concentration had higher serum creatinine level (62.3±17.1μmol/L vs 51.5±12.6μmol/L, P<0.01), lower fractional excretion of urate (4.5% vs 6.8%, P<0.03) and higher reticulocyte count (median 219500/mm(3) vs 144000/mm(3), P=0.08) compared to the other patients.

CONCLUSION

Hyperuricemia and gout are not a clinical problem in sickle cell disease in our country. Nevertheless, our findings indicate that kidney function has to be fully explored if serum uric acid level is elevated or significantly deteriorates during follow-up. Serum uric acid level could be an early marker of renal dysfunction in sickle cell disease patients.