Low vitamin D status in children with sickle cell disease

Racial and Ethnic Disparities in Metabolic Bone Disease

Racial and ethnic disparities exist in the prevalence and management of osteoporosis, metastatic cancer, and sickle cell disease. Despite being the most common metabolic bone disease, osteoporosis remains underscreened and undertreated among Black women. Skeletal-related events in metastatic cancer include bone pain, pathologic fractures, and spinal cord compression. Disparities in screening for and treating skeletal-related events disproportionately affect Black patients. Metabolic bone disease contributes significantly to morbidity in sickle cell disease; however, clinical guidelines for screening and treatment do not currently exist. Clinical care recommendations are provided to raise awareness, close health care gaps, and guide future research efforts.

Management of the Sickle Cell Trait: An Opinion by Expert Panel Members

The number of individuals with the sickle cell trait exceeds 300 million worldwide, making sickle cell disease one of the most common monogenetic diseases globally. Because of the high frequency of sickle cell disease, reproductive counseling is of crucial importance. In addition, unlike other carrier states, Sickle Cell Trait (SCT) seems to be a risk factor for several clinical complications, such as extreme exertional injury, chronic kidney disease, and complications during pregnancy and surgery. This expert panel believes that increasing knowledge about these clinical manifestations and their prevention and management can be a useful tool for all healthcare providers involved in this issue.

Mechanisms of Bone Impairment in Sickle Bone Disease

Sickle bone disease (SBD) is a chronic and invalidating complication of Sickle cell disease (SCD), a multisystem autosomal recessive genetic disorder affecting millions of people worldwide. Mechanisms involved in SBD are not completely known, especially in pediatric age. Among the hypothesized pathogenetic mechanisms underlying SBD are bone marrow compensatory hyperplasia and bone ischemic damage, both secondary to vaso-occlusive crisis (VOC), which leads to cell sickling, thus worsening local hypoxia with a negative impact on osteoblast recruitment. Furthermore, the hypoxia is a strong activator of erythropoietin, which in turn stimulates osteoclast precursors and induces bone loss. Hemolysis and iron overload due to a chronic transfusion regimen could also contribute to the onset of bone complications. Vitamin D deficiency, which is frequently seen in SCD subjects, may worsen SBD by increasing the resorptive state that is responsible for low bone mineral density, acute/chronic bone pain, and high fracture risk. An imbalance between osteoblasts and osteoclasts, with a relative decrease of osteoblast recruitment and activity, is a further possible mechanism responsible for the impairment of bone health in SCD. Moreover, delayed pubertal growth spurt and low peak bone mass may explain the high incidence of fracture in SCD adolescents. The aim of this review was to focus on the pathogenesis of SBD, updating the studies on biochemical, instrumental, and biological markers of bone metabolism. We also evaluated the growth development and endocrine complications in subjects affected with SCD.

Vitamin D supplementation for sickle cell disease

BACKGROUND

Sickle cell disease (SCD) is a genetic chronic haemolytic and pro-inflammatory disorder. With increased catabolism and deficits in energy and nutrient intake, individuals with SCD suffer multiple macro- and micro-nutritional deficiencies, including vitamin D deficiency. This is an update of a previous review.

OBJECTIVES

To investigate the effects of vitamin D supplementation in children and adults with SCD and to compare different dose regimens. To determine the effects of vitamin D supplementation on general health (e.g. growth status and health-related quality of life), on musculoskeletal health (including bone mineral density, pain crises, bone fracture and muscle health), on respiratory health (including lung function, acute chest syndrome, acute exacerbation of asthma and respiratory infections) and the safety of vitamin D supplementation.

SEARCH METHODS

We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. Date of last search: 19 March 2020. We also searched database such as PubMed, clinical trial registries and the reference lists of relevant articles and reviews. Date of last search: 14 January 2020.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs comparing oral administration of any form of vitamin D supplementation at any dose and for any duration to another type or dose of vitamin D or placebo or no supplementation in people with SCD, of all ages, gender, and phenotypes.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data and assessed the risk of bias of the included studies. They used the GRADE guidelines to assess the quality of the evidence.

MAIN RESULTS

Vitamin D versus placebo One double-blind RCT (n = 39) compared oral vitamin D3 (cholecalciferol) supplementation (20 participants) to placebo (19 participants) for six weeks. Only 25 participants completed the full six months of follow-up. The study had a high risk of bias due to incomplete outcome data, but a low risk of bias for randomisation, allocation concealment, blinding (of participants, personnel and outcome assessors) and selective outcome reporting; and an unclear risk of other biases. Vitamin D supplementation probably led to higher serum 25(OH)D levels at eight weeks, mean difference (MD) 29.79 (95% confidence interval (CI) 26.63 to 32.95); at 16 weeks, MD 12.67 (95% CI 10.43 to 14.90); and at 24 weeks, MD 15.52 (95% CI 13.50 to 17.54) (moderate-quality evidence). There was little or no difference in adverse events (tingling of lips or hands) between the vitamin D and placebo groups, risk ratio 3.16 (95% CI 0.14 to 72.84) (low-quality evidence). Vitamin D supplementation probably caused fewer pain days compared to the placebo group at eight weeks, MD -10.00 (95% CI -16.47 to -3.53) (low-quality evidence), but probably led to a lower (worse) health-related quality of life score (change from baseline in physical functioning PedsQL scores); at both 16 weeks, MD -12.56 (95% CI -16.44 to -8.69) and 24 weeks, MD -12.59 (95% CI -17.43 to -7.76), although this may not be the case at eight weeks (low-quality evidence). Vitamin D supplementation regimens compared Two double-blind RCTs (83 participants) compared different regimens of vitamin D. One RCT (n = 62) compared oral vitamin D3 7000 IU/day to 4000 IU/day for 12 weeks, while the second RCT (n = 21) compared oral vitamin D3 100,000 IU/month to 12,000 IU/month for 24 months. Both RCTs had low risk of bias for blinding (of participants, personnel and outcome assessors) and incomplete outcome data, but the risk of selective outcome reporting bias was high. The bias from randomisation and allocation concealment was low in one study but not in the second. There was an unclear risk of other biases. When comparing oral vitamin D 100,000 IU/month to 12,000 IU/month, the higher dose may have resulted in higher serum 25(OH)D levels at one year, MD 16.40 (95% CI 12.59 to 20.21) and at two years, MD 18.96 (95% CI 15.20 to 22.72) (low-quality evidence). There was little or no difference in adverse events between doses (low-quality evidence). There were more episodes of acute chest syndrome in the high-dose group, at one year, MD 0.27 (95% CI 0.02 to 0.52) but there was little or no difference at two years, MD 0.09 (95% CI -0.04 to 0.22) (moderate-quality evidence). At one year and two years there was also little or no difference between the doses in the presence of pain (moderate-quality evidence) or forced expiratory volume in one second % predicted. However, the high-dose group had lower values for % predicted forced vital capacity at both one and two years, MD -7.20% predicted (95% CI -14.15 to -0.25) and MD -7.10% predicted (95% CI -14.03 to -0.17), respectively. There were little or no differences between dose regimens in the muscle health of either hand or the dominant hand. The study comparing oral vitamin D3 7000 IU/day to 4000 IU/day (21 participants) did not provide data for analysis, but median serum 25(OH)D levels were reported to be lower in the low-dose group at both six and 12 weeks. At 12 weeks the median serum parathyroid hormone level was lower in the high-dose group.

AUTHORS' CONCLUSIONS

We included three RCTs of varying quality. We consider that the current evidence presented in this review is not of sufficient quality to guide clinical practice. Until further evidence becomes available, clinicians should consider the relevant existing guidelines for vitamin D supplementation and dietary reference intakes for calcium and vitamin D. Well-designed RCTs of parallel design, are required to determine the effects and the safety of vitamin D supplementation as well as to assess the relative benefits of different doses in children and adults with SCD.

Evaluation of the effectiveness of prophylactic oral vitamin D (cholecalciferol) in children with sickle cell disease

BACKGROUND

Vitamin D (25(OH)D) deficiency has become an emerging public health problem due to its influence on skeletal and extraskeletal diseases. Bone health in patients with sickle cell disease (SCD) is especially compromised and they are more likely to have 25(OH)D deficiency than the general population. Despite this, there is little information on the efficacy of vitamin D3 (vitD3) prophylaxis and its role in improving bone mineral density (BMD) in this population.

PROCEDURES

A prospective, longitudinal, single-center study was conducted with 136 children with SCD monitored at a tertiary referral hospital for SCD. Demographic, clinical and management data, 25(OH)D levels and bone densitometries (DXA) were collected.

RESULTS

Eighty patients were included. There are significant differences between the means of each of 25(OH)D levels as a function of whether the patient started prophylactic treatment as an infant or not (35.71 vs. 27.89 ng/ml, respectively [p = .014]). In multivariate analysis, 800 IU daily dose was shown as a protective factor (p = .044) to reach optimal blood levels (≥30 ng/ml). According to Kaplan-Meier curves, patients younger than 10 years reached optimal levels earlier than older (p = .002), as well as those who were not being treated with hydroxyurea (p = .039).

CONCLUSIONS

VitD3 prophylaxis is a safe practice in SCD. It is important to start this prophylactic treatment when the child is an infant. The daily regimen with 800 IU could be more effective for reaching levels ≥30 ng/ml, and, especially in preadolescent and adolescent patients, we should raise awareness about the importance of good bone health.

Effect of High-dose Vitamin A Supplementation in Children With Sickle Cell Disease: A Randomized, Double-blind, Dose-finding Pilot Study

Suboptimal vitamin A status (serum retinol <30 µg/dL) is associated with poor clinical outcomes in children with the hemoglobin-SS disease (HbSS), and supplementation with the recommended daily allowance of retinol is ineffective in improving vitamin A status. In a single-center randomized blinded dose-finding pilot study, we compared vitamin A and nutritional status in children with HbSS to healthy children and explored the impact of high-dose supplementation on the primary outcome serum vitamin A status. Exploratory outcomes included hematologic, nutritional, immunologic, and muscle function status in children with HbSS. A mixed-effects linear regression model evaluated associations between vitamin A dose, serum retinol, and exploratory outcomes. Twenty healthy children participated, and 22 subjects with HbSS were randomized to oral 3000 or 6000 IU/d retinol for 8 weeks; 21 subjects completed all evaluations. Serum retinol, growth, and nutritional status were all suboptimal in HbSS subjects at baseline, and supplementation did not change vitamin A status. Fetal hemoglobin (Δ=2.5, 95% confidence interval [CI], 0.5-4.3), mean corpuscular volume (Δ=2.7, 95% CI, 0.7-4.7), mean corpuscular hemoglobin (Δ=1.4, 95% CI, 0.5-2.3), and mean corpuscular hemoglobin concentration (Δ=0.5, 95% CI, 0.1-0.9) all improved with supplementation. Mild improvements in erythrocyte indices, growth status, and muscle function occurred independent of hydroxyurea use.

Vitamin D supplementation and pain-related emergency department visits in children with sickle cell disease

OBJECTIVES

Sickle cell disease (SCD) is the most prevalent inherited hematological disorder and affects 100,000 individuals in the United States. Pain is the most common cause of emergency department (ED) visits in the SCD population, which profoundly affects quality of life. Vitamin D supplementation is a potential target for reducing pain. Thus, the goal of the present study was to identify the prevalence of vitamin D deficiency and explore the relationship between vitamin D supplementation and ED visits in pediatric patients with SCD.

DESIGN

We conducted a retrospective chart review of 110 patients with SCD aged 8-16 years who had at least one ED visit for SCD pain during the 6-year study period. Patients were categorized into three vitamin D supplementation groups: patients who did not receive supplementation, patients supplemented with 25-hydroxyvitamin D levels (< 30 ng/mL), and patients supplemented with at least one sufficient 25-hydroxyvitamin D level (≥ 30 ng/mL).

RESULTS

Overall, 45 % of patients were vitamin D deficient. Only 20 % of patients had sufficient vitamin D levels. This number increased to 55 % when examining only patients who did not receive vitamin D supplementation. For patients supplemented with vitamin D, the number of ED visits was significantly lower after they reached the sufficient range (≥ 30 ng/mL), p = 0.03.

CONCLUSIONS

Our findings indicate that reductions in the number of pain-related ED visits may be achieved by normalizing 25-hydroxyvitamin D levels with supplementation. In addition, findings highlight the need for screening and vitamin D supplementation being incorporated into routine care for pediatric patients with SCD.

Review of Sickle Cell Disease and Spinal Pathology

STUDY DESIGN

Sickle cell disease (SCD) is a relatively common blood disorder that has profound implications on the musculoskeletal system and particularly the spine; however, there is a paucity of data in the literature discussing this important topic.

OBJECTIVES

(1) To elucidate common spinal pathologies affecting patients with SCD, as well as the medical and surgical treatments available for these patients. (2) To discuss indications for surgical management of spinal complications of SCD and important for orthopedic surgeons when taking patients with SCD to the operating room.

METHODS

A narrative review of the literature was performed.

RESULTS

Patients with SCD have a significantly higher risk of developing spinal pathologies including vertebral osteomyelitis, compression fracture, vertebral vaso-occlusive crises, and osteoporosis, among others. In addition, patients with sickle cell disease are particularly susceptible to developing perioperative and post-operative complications including surgical site infection, implant malfunction, and vertebral body compression fracture. Postoperatively patients with SCD are prone to developing complications and adequate hydration is necessary in order to reduce complications of SCD.

CONCLUSIONS

Several spinal pathologies may arise secondary to SCD and distinguishing these pathologies from one another may be challenging due to similarities in symptoms and inflammatory markers. Although most patients with SCD can benefit from conservative treatment involving rest, symptomatic therapy, antibiotic therapy, and/or orthosis, surgical intervention may be indicated in certain cases. It is preferable to avoid surgery in patients with SCD due to an increased risk of complications such as wound infection and vaso-occlusive crisis.

Asthma in children with sickle cell disease

PURPOSE OF REVIEW

Asthma is common in children with sickle cell disease (SCD) and appears to be associated with increased morbidity. Providers caring for children with SCD have struggled with the question of whether asthma exists as a true comorbidity or whether certain aspects of the chronic inflammatory disease gives children with SCD an asthma-like phenotype.

RECENT FINDINGS

Clinical signs and symptoms seen in children with asthma in the general population, such as wheezing, airway hyperresponsiveness, atopy, elevated leukotrienes, and abnormal lung function are seen in children with SCD both with and without a diagnosis of asthma.

SUMMARY

Current evidence highlights that the presence of lung disease in children with SCD has significant implications irrespective of the underlying cause, including asthma. Further research should focus on well tolerated and effective interventions to prevent disease-related complications for children with pulmonary complications of SCD.

Height-corrected low bone density associates with severe outcomes in sickle cell disease: SCCRIP cohort study results

Low bone mineral density (BMD) disproportionately affects people with sickle cell disease (SCD). Growth faltering is common in SCD, but most BMD studies in pediatric SCD cohorts fail to adjust for short stature. We examined low BMD prevalence in 6- to 18-year-olds enrolled in the Sickle Cell Clinical Research and Intervention Program (SCCRIP), an ongoing multicenter life span SCD cohort study initiated in 2014. We calculated areal BMD for chronological age and height-adjusted areal BMD (Ht-aBMD) z scores for the SCCRIP cohort, using reference data from healthy African American children and adolescents enrolled in the Bone Mineral Density in Childhood Study. We defined low BMD as Ht-aBMD z scores less than or equal to -2 and evaluated its associations with demographic and clinical characteristics by using logistic regression analyses. Of the 306 children and adolescents in our study cohort (mean age, 12.5 years; 50% female; 64% HbSS/Sβ0-thalassemia genotype; 99% African American), 31% had low areal BMD for chronological age z scores and 18% had low Ht-aBMD z scores. In multivariate analyses, low Ht-aBMD z scores associated with adolescence (odds ratio [OR], 7.7; 95% confidence interval [CI], 1.94-30.20), hip osteonecrosis (OR, 4.0; 95% CI, 1.02-15.63), chronic pain (OR, 10.4; 95% CI, 1.51-71.24), and hemoglobin (OR, 0.74; 95% CI, 0.57-0.96). Despite adjusting for height, nearly 20% of this pediatric SCD cohort still had very low BMD. As the SCCRIP cohort matures, we plan to prospectively evaluate the longitudinal relationship between Ht-aBMD z scores and markers of SCD severity and morbidity.

Endocrine and metabolic complications in children and adolescents with Sickle Cell Disease: an Italian cohort study

BACKGROUND

Children with Sickle Cell Disease (SCD) show endocrine complications and metabolic alterations. The physiopathology of these conditions is not completely understood: iron overload due to chronic transfusions, ischemic damage, and inflammatory state related to vaso-occlusive crises may be involved. Aims of this study were to evaluate the growth pattern, endocrine complications, and metabolic alterations and to detect the relationship between these conditions and the SCD severity in affected children and adolescents.

METHODS

Fifty-two children and adolescents with SCD [38 homozygous sickle hemoglobin (HbSS) and 14 heterozygous sickle hemoglobin (HbSC); age range 3-18 years] were recruited. Anthropometric [height, body mass index (BMI), arm span, sitting height, target height (TH), and pubertal status] and laboratory [blood cell counts, hemolysis indices, metabolic and nutritional status indices and hormonal blood levels] data were evaluated. The SCD severity was defined according to hematological and clinical parameters.

RESULTS

Height-SDS adjusted for TH and BMI-SDS were significantly higher in HbSC children than in HbSS ones. Forty-eight out of 52 patients (92%) had at least one metabolic and/or endocrine alteration: insufficiency/deficiency of vitamin D (84.7%), insulin resistance (11.5%), growth hormone deficiency (3.8%), subclinical hypothyroidism (3.8%), and hypogonadism (1.9%). Levels of vitamin D were significantly and negatively correlated with clinical indicators of the SCD severity. Subjects with HbSS genotype show significant lower levels of both insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein 3 than children with HbSC. In the study population IGF-1 values were significantly and positively correlated with Hb and negatively with lactate dehydrogenase.

CONCLUSIONS

Metabolic alterations and endocrine complications are very common in children and adolescents with SCD. A regular follow-up is necessary to identify subjects at risk for complications to precociously start an appropriate treatment and to improve the quality of life of SCD patients.

Vitamin D Intake and Status of Children With Sickle Cell Disease in Montreal, Canada

Sickle cell disease (SCD) and vitamin D deficiency share manifestations such as bone complications and bony pains. Canadian SCD children are characterized by compromised sun exposure all year long and potential dietary deficiency, which combined to SCD-causing high nutritional demands, may lead to impaired vitamin D status. The objectives of this study were to document vitamin D status and intake and assess the relationship between vitamin D status and SCD-related outcomes in Canadian children with SCD followed in a tertiary pediatric center. Our study population included 119 children (47% males, median age [interquartile range]: 11.1 [9.2-14.8]) mainly of Haitian and Sub-Saharan African origin who had at least one measure of serum 25-hydroxyvitamin D (25OHD) performed between June 2015 and February 2017. Predominant genotypes were homozygous hemoglobin S (60%) and sickle hemoglobin-C (32%). Vitamin D deficiency (25OHD<30 nmol/L) and insufficiency (30 to 49 nmol/L) were present in 31% and 37% of children, respectively. Vitamin D-sufficient children (25OHD>50 nmol/L) had higher hemoglobin levels, lower leukocyte, reticulocyte, and neutrophil counts, compared with vitamin D-deficient and insufficient children. Vitamin D intake was low and modestly correlated to serum 25OHD levels. Acute SCD complications in the preceding 2 years were not associated with vitamin D status in these children.

Vitamin D and Nonskeletal Complications among Egyptian Sickle Cell Disease Patients

Lower levels of vitamin D have been documented in many patients with sickle cell disease (SCD), but data are still inconclusive regarding the association between vitamin D deficiency (VDD) and the occurrence or the severity of various SCD complications. Our study aimed to detect the prevalence of vitamin D deficiency among Egyptian patients with SCD and to associate it with the clinical course of the disease. We measured the level of 25-hydroxy vitamin D in 140 children (age from 4.3 to 15.5years), 80 patients with SCD and 60 controls using enzyme-linked immunosorbent assay. Vitamin D was deficient in 60% of SCD compared to 26.7% of controls. Severe VDD was significantly higher in SCD patients than controls. Patients were divided into 2 groups; Normal group (32 patients) and Deficient group (48 patients). There were statistically significant differences between the 2 groups regarding their age, height percentile, the presence of clinical jaundice, and osseous changes (P values 0.043, 0.024, 0.001, and 0.015, respectively). Hemoglobin and hematocrit values were significantly lower in Deficient group (P values 0.022 and 0.004, respectively) while the levels of aspartate aminotransferase, lactate dehydrogenase, and total and indirect bilirubin were significantly higher in the same group (P values 0.006, 0.001, 0.038, and 0.016, respectively). The frequency of blood transfusions, hospitalization, and vasoocclusive crisis previous year as well as the history of bone fracture and recurrent infections proved to be significantly higher in Deficient group. These findings suggest that VDD may play a role in the pathogenesis of hemolysis and other complication of SCD. Vitamin D monitoring and supplementation in patients with SCD should be implemented as a standard of care to potentially improve health outcomes in these affected patients.

Dietary intakes and nutritional status of children with sickle cell disease at the Princess Marie Louise Hospital, Accra - a survey

Background

Sickle cell disease (SCD) is a chronic genetic blood disorder common among people of African descent, which places nutritional burden among affected individuals. The aim of the study was to determine the dietary intake and nutritional status of children with SCD.

Method

This was a cross sectional study that involved 120 children with SCD aged 3-12 years at the paediatric outpatient department of Princess Marie Louise Hospital (PML) in Accra. A semi-structured questionnaire was used to take information on participant's demographic characteristics and clinical data were obtained from their medical records. Dietary data were obtained using 24-h dietary recall and food frequency questionnaire. Height and weight were measured for participants and their haemoglobin levels were determined to assess their anaemia status.

Results

Intakes of participants were below recommendations for most nutrients, particularly for calcium and antioxidant vitamins (vitamin C and E). Adequacy of nutrient intake declined with age and children with genotype HbSS had a lower tendency to meet dietary recommendations (aOR = 0.45, 95% CI: 0.18, 1.10; p = 0.084). More than a third of the study children (38%) were malnourished, with older children having a tendency to be malnourished compared to the younger ones. Children with the SS genotype were more likely to be stunted (aOR = 3.48, 95% CI: 1.10, 11.01), compared to other genotypes.

Conclusion

Malnutrition is prevalent among children with SCD and hence there is the need to develop comprehensive management coupling nutritional therapy to medical care to improve their nutritional status. Nutritional management should focus much on calcium-rich foods and antioxidants nutrients particularly vitamin C and E to reduce rapid erythrocyte haemolysis and chronic anaemia.

Response to Long-term Vitamin D Therapy for Bone Disease in Children With Sickle Cell Disease

Patients with sickle cell disease (SCD) are at risk for bone fragility from multiple factors including vitamin D deficiency. To date, no studies have evaluated the efficacy and safety of long-term vitamin D therapy for bone disease in children with SCD. We report a cohort of 4 children with SCD found to have severe vitamin D deficiency, secondary hyperparathyroidism, and abnormal bone mineral density treated with monthly high-dose oral cholecalciferol over 2 years. All patients exhibited a positive response to therapy without hypervitaminosis D or hypercalcemia. Further studies are needed to standardize guidelines for optimal vitamin D dosing and prevention of toxicity.

The Epidemiology and Management of Lung Diseases in Sickle Cell Disease: Lessons Learned from Acute and Chronic Lung Disease in Cystic Fibrosis

Although sickle cell disease and cystic fibrosis are two of the most common monogenic diseases presenting in childhood worldwide, cystic fibrosis and sickle cell disease enjoy vastly different funding and collaborative research efforts. Pulmonary complications in cystic fibrosis have well established guidelines and multidisciplinary involvement focusing on comorbidities, routine monitoring, infectious complications, nutrition, and treatment recommendations. These guidelines can provide a framework on which to build knowledge of lung disease in sickle cell disease.

The Association of Serum 25-Hydroxyvitamin D With Biomarkers of Hemolysis in Pediatric Patients With Sickle Cell Disease

Although vitamin D deficiency (VDD) has been linked to anemia among sickle cell disease (SCD), its relationship with hemolysis is unclear. Serum 25-hydroxyvitamin D and biomarkers of hemolysis (hemoglobin [Hb]/hematocrit, reticulocyte percentage, absolute reticulocyte, and lactate dehydrogenase [LDH] levels) in 36 hydroxyurea-naive SCD children were quantified. Correlations were significantly positive with Hb/hematocrit (r=0.40, P=0.017; r=0.45, P=0.006, respectively); inverse with reticulocyte percentage, absolute reticulocyte, and LDH (r=-0.44, P=0.008; r=-0.47, P=0.007; r=-0.45, P=0.007, respectively). In VDD groups, Hb was lower (P=0.014), reticulocyte counts and LDH were higher (P=0.047 and 0.003, respectively). Serum 25-hydroxyvitamin D correlated with biomarkers of hemolysis in SCD and VDD may play a role in SCD pathogenesis.

Prevalence of Vitamin D Deficiency Varies Widely by Season in Canadian Children and Adolescents with Sickle Cell Disease

Sickle cell disease (SCD) is an inherited disorder caused by a variant (rs334) in the β-globin gene encoding hemoglobin. Individuals with SCD are thought to be at risk of vitamin D deficiency. Our aim was to assess serum 25-hydroxyvitamin D (25OHD) concentrations, estimate deficiency prevalence, and investigate factors associated with 25OHD concentrations in children and adolescents with SCD attending BC Children's Hospital in Vancouver, Canada. We conducted a retrospective chart review of SCD patients (2-19 y) from 2012 to 2017. Data were available for n = 45 patients with n = 142 25OHD measurements assessed using a EUROIMMUN analyzer (EUROIMMUN Medizinische Labordiagnostika AG, Lübeck, Germany). Additional data were recorded, including age, sex, and season of blood collection. Linear regression was used to measure associations between 25OHD concentration and predictor variables. Overall, mean ± SD 25OHD concentration was 79 ± 36 nmol/L; prevalence of low 25OHD concentrations (<30, <40, and <75 nmol/L) was 5%, 17% and 50%, respectively. Mean 25OHD concentrations measured during Jul-Sep were higher (28 (95% confidence interval CI: 16-40) nmol/L higher, P < 0.001) compared to Jan-Mar. Vitamin D deficiency rates varied widely by season: Based on 25OHD <30 nmol/L, prevalence was 0% in Oct-Dec and 6% in Jan-Mar; based on <40 nmol/L, prevalence was 0% in Oct-Dec and 26% in Jan-Mar.

Vitamin D Deficiency and Its Association with Inflammatory Markers, Lipid Profile and Regulatory T-cells in Pediatric Sickle Cell Disease Patients

We investigated vitamin D deficiency in pediatric sickle cell disease patients and its association with selected bone, lipid and inflammatory parameters. The study included 64 patients (33 SS and 31 SB) and 21 carriers (AS). Blood was obtained to assess levels of vitamin D, WBC, CRP, Ca, P, ALP, PTH, triglyceride, total cholesterol, LDL, VLDL, HDL, IL-2, IL-12, TNF-α, IL-4, IL-6, IL-10 and regulatory T cells. The patients were grouped according to their genotype (SS, SB) and vitamin D status (low or normal). Carriers were also grouped as low or normal vitamin D. Laboratory findings were similar between low and normal Vit D groups in SS, SB and AS genotypes except a lower IL-12 in SB-low vitamin D compared SB-normal vitamin D group. Acute chest syndrome was more frequent in SS-low Vit D (63%) compared to SS-normal Vit D (25%), SB-low Vit D (21%) and SB-normal Vit D (33%) (P = 0.045). Both SS and SB with low vitamin D had higher VLDL (P = 0.006 and P = 0.022), TNF-α (P = 0.001) and regulatory T cells (P = 0.000) compared to AS-low vitamin D. Both SS and SB with normal vitamin D had higher levels of regulatory T cells (P = 0.000) compared to AS-normal vitamin D. Vit D was not a modifier of selected inflammation, bone and lipid parameters in sickle cell disease. Acute chest syndrome was comparably more frequent in SS-low vitamin D. Increase of regulatory T cells in the patients was a result of chronic inflammation in sickle cell disease.

The role of nutrition in the pathophysiology and management of sickle cell disease among children: A review of literature

Sickle cell disease (SCD) is one of the common inherited blood disorders in humans and has been associated with decreased dietary intake which results in poor nutritional status and impaired growth. Nutrition is one of the most important but often forgotten aspect of care of patients with chronic disorders and there have been emerging concern in literature on increased nutritional needs of SCD patients. This paper sought to review the available literature on the roles of individual nutrients in the pathophysiology and management of SCD among children. Children with SCD have been shown to exhibit suboptimal status with respect to both macronutrients and micronutrients. Thus, nutrition could play an important role in the management of SCD. However, there is paucity of evidence coming from trials with large sample sizes to support the suggestion that supplementation with various nutrients that have been considered in this review will be helpful.

Growth and Growth hormone - Insulin Like Growth Factor -I (GH-IGF-I) Axis in Chronic Anemias

Anaemia is a global public health problem affecting both developing and developed countries with major consequences for human health as well as social and economic development. It occurs at all stages of the life cycle, but is more prevalent in pregnant women and young children. Iron deficiency anaemia (IDA) was considered to be among the most important contributing factors to the global burden of disease. Prolonged and/or chronic anemia has a negative effect on linear growth especially during the rapid phases (infancy and puberty). Additionally infants with chronic IDA have delayed cognitive, motor, and affective development that may be long-lasting. In view of the significant impact of chronic anemias on growth, pediatricians endocrinologists and hematologists should advocate primary prevention and screening for growth disturbance in these forms of anemias. The extent of the negative effect of different forms of chronic anemias on linear growth and its possible reversibilty is addressed in this review. The possible mechanisms that may impair growth in the different forms of anemias are addressed with special attention to their effect on the growth hormone (GH) – insulin like growth factor -I (IGF-I). (www.actabiomedica.it)

Vitamin D supplementation for sickle cell disease

BACKGROUND

Sickle cell disease is a genetic chronic haemolytic and pro-inflammatory disorder. The clinical manifestations of sickle cell disease result from the presence of mutations on the beta globin genes that generate an abnormal haemoglobin product (called haemoglobin S) within the red blood cell. Sickle cell disease can lead to many complications such as acute chest syndrome, stroke, acute and chronic bone complications (including painful vaso-occlusive crisis, osteomyelitis, osteonecrosis and osteoporosis). With increased catabolism and deficits in energy and nutrient intake, individuals with sickle cell disease suffer multiple macro- and micro-nutritional deficiencies, including vitamin D deficiency. Since vitamin D maintains calcium homeostasis and is essential for bone mineralisation, its deficiency may worsen musculoskeletal health problems encountered in sickle cell disease. Therefore, there is a need to review the effects and the safety of vitamin D supplementation in sickle cell disease.

OBJECTIVES

To investigate the hypothesis that vitamin D supplementation increases serum 25-hydroxyvitamin D level in children and adults with sickle cell disease.To determine the effects of vitamin D supplementation on general health such as growth status and health-related quality of life; on musculoskeletal health including bone mineral density, pain crises, bone fracture and muscle health; on respiratory health which includes lung function tests, acute chest syndrome, acute exacerbation of asthma and respiratory infections; and the safety of vitamin D supplementation in children and adults with sickle cell disease.

SEARCH METHODS

We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched database such as PubMed, clinical trial registries and the reference lists of relevant articles and reviews.Date of last search: 15 December 2016.

SELECTION CRITERIA

Randomised controlled studies and quasi-randomised controlled studies (controlled clinical studies) comparing oral administration of any form of vitamin D supplementation to another type of vitamin D or placebo or no supplementation at any dose and for any duration, in people with sickle cell disease, of all ages, gender, and phenotypes including sickle cell anaemia, haemoglobin sickle cell disease and sickle beta-thalassaemia diseases.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data and assessed the risk of bias of the included study. They used the GRADE guidelines to assess the quality of the evidence.

MAIN RESULTS

One double-blind randomised controlled study including 46 people with sickle cell disease (HbSS, HbSC, HbSβ+thal and HbSβ0thal) was eligible for inclusion in this review. Of the 46 enrolled participants, seven withdrew before randomisation leaving 39 participants who were randomised. Only 25 participants completed the full six months of follow up. Participants were randomised to receive oral vitamin D3 (cholecalciferol) (n = 20) or placebo (n = 19) for six weeks and were followed up to six months. Two participants from the treatment group have missing values of baseline serum 25-hydroxyvitamin D, therefore the number of samples analysed was 37 (vitamin D n = 18, placebo n = 19).The included study had a high risk of bias with regards to incomplete outcome data (high dropout rate in the placebo group), but a low risk of bias for other domains such as random sequence generation, allocation concealment, blinding of participants, personnel and outcome assessors, selective outcome reporting; and an unclear risk of other biases.Compared to the placebo group, the vitamin D group had significantly higher serum 25-hydroxyvitamin D (25(OH)D) levels at eight weeks, mean difference 29.79 (95% confidence interval 26.63 to 32.95); at 16 weeks, mean difference 12.67 (95% confidence interval 10.43 to 14.90); and at 24 weeks, mean difference 15.52 (95% confidence interval 13.50 to 17.54). We determined the quality of the evidence for this outcome to be moderate. There was no significant difference of adverse events (tingling of lips or hands) between the vitamin D and placebo groups, risk ratio 3.16 (95% confidence interval 0.14 to 72.84), but the quality of the evidence was low. Regarding the frequency of pain, the vitamin D group had significantly fewer pain days compared to the placebo group, mean difference -10.00 (95% confidence interval -16.47 to -3.53), but again the quality of the evidence was low. Furthermore, the review included physical functioning PedsQL scores which was reported as absolute change from baseline. The vitamin D group had a lower (worse) health-related quality of life score than the placebo group but this was not significant at eight weeks, mean difference -2.02 (95% confidence interval -6.34 to 2.30). However, the difference was significant at both 16 weeks, mean difference -12.56 (95% confidence interval -16.44 to -8.69) and 24 weeks, mean difference -12.59 (95% confidence interval -17.43 to -7.76). We determined the quality of evidence for this outcome to be low.

AUTHORS' CONCLUSIONS

We included only one low-quality clinical study which had a high risk of bias with regards to incomplete outcome data. Therefore, we consider that the evidence is not of sufficient quality to guide clinical practice. Until further evidence becomes available, clinicians should consider the relevant existing guidelines for vitamin D supplementation (e.g. the Endocrine Society Clinical Practice Guidelines) and dietary reference intakes for calcium and vitamin D (e.g. from the USA Institute of Medicine). Evidence of vitamin D supplementation in sickle cell disease from high quality studies is needed. Well-designed, randomised, placebo-controlled studies of parallel design, are required to determine the effects and the safety of vitamin D supplementation in children and adults with sickle cell disease.

Vitamin D Deficiency in Adult Sickle Cell Patients

INTRODUCTION

Vitamin D levels in adult black Americans with sickle cell disease (SCD) are comparatively lower than those found in the general population of black Americans. The objectives of this study were to examine the prevalence of Vitamin D deficiency (VDD) in adults with various subtypes of sickle cell disease and identify risk factors for vitamin D deficiency.

METHODS

In a retrospective study serum Vitamin D25(OH)D and/or VitaminD1,25(OH)2D levels were obtained in 120 subjects with sickle cell disease. Baseline studies also included LFTs, total protein, albumin, total bilirubin, and creatinine levels. In a portion of subjects that were treated with oral ergocalciferol vitamin D levels and chemistries were obtained within 6 months of treatment. Data was statistically analyzed with Welch two sample t-tests and individual simple linear regressions (including logarithmic values) for each variable.

RESULTS

Vitamin D25(OH)D levels were found to be significantly lower in a group of subjects with Hgb SS disease, than in a group with other subtypes of sickle cell disease. In both groups combined, significant (p = 0.05) and clinically suggestive negative correlations with Vitamin D25(OH)D were seen for total bilirubin and total protein, respectively. When total bilirubin and total protein levels were compared between the Hgb SS and HgbS/other groups, t-test revealed these levels were significantly higher in the Hgb SS group levels at p < 0.001 and p = 0.005, respectively.

IMPLICATIONS

Low total Vitamin D25(OH)D levels in adults with sickle cell disease may be a reflection of chronic inflammation and overall disease severity.

Tartrate-Resistant Acid Phosphatase 5b in Young Patients With Sickle Cell Disease and Trait Siblings: Relation to Vasculopathy and Bone Mineral Density

Bone involvement is a frequent cause of acute morbidity in sickle cell disease (SCD). Tartrate-resistant acid phosphatase 5b (TRACP 5b), a bone resorption marker, is produced specifically by activated osteoclasts. We assessed bone mineral density (BMD) in 30 young patients with SCD and 17 asymptomatic patients with sickle cell trait (SCT) compared with 32 healthy controls and determined TRACP 5b levels in relation to vascular complications. Serum ferritin, alkaline phosphatase (ALP), and TRACP 5b were measured. Echocardiography was performed with assessment of BMD using dual energy X-ray absorptiometry (DXA). The BMD was decreased in patients with SCD compared with SCT and controls (P = .005), with no significant difference between the latter 2 groups. Patients with SCD had higher incidence of bone complications than SCT group and controls (P = .03). The SCD group with abnormal DXA scan had higher ferritin and ALP than normal BMD. Serum TRACP 5b was significantly higher in patients with SCD than SCT and controls (P = .003). The TRACP 5b levels were associated with severe vaso-occlusive crisis (P = .022). Patients treated with hydroxyurea and those on chelation therapy had lower TRACP 5b levels than untreated patients. The TRACP 5b level was positively correlated with lactate dehydrogenase, while there was no relation with ferritin, ALP, or BMD. We suggest that bone complications frequently occur in SCD as reflected by low BMD and high ALP and TRACP 5b. Hemolysis and iron overload may be involved in the occurrence of these complications. The lack of correlation between abnormal DXA scan and high TRACP 5b suggests that bone disease in SCD is multifactorial.

Safety and Efficacy of High-dose Daily Vitamin D3 Supplementation in Children and Young Adults With Sickle Cell Disease

Suboptimal vitamin D (vit D) status (<32 ng/mL) is ubiquitous among African American children with type SS sickle cell disease (SCD-SS). The vit D supplemental dose to normalize vit D status is unknown. Five to 20-year-old African American children with (n=21) and without (n=23) SCD-SS were randomized to vit D3 supplementation (4000 or 7000 IU/d) and evaluated at 6 and 12 weeks for changes in vit D and SCD status. A dose was considered unsafe if serum calcium was elevated associated with elevated serum 25 hydroxyvitamin D (25(OH)D). At baseline 95% of subjects with SCD-SS and 87% of healthy controls had suboptimal vit D status (mean±SD, 19.2±7.2 and 22.3±9.3 ng/mL, respectively). After 12 weeks supplementation, both D3 doses were safe and well tolerated. Neither group achieved the a priori efficacy criterion of 25(OH)D≥32 ng/mL in >80% of subjects (45% in SCD-SS and 63% in controls). However, for both subjects with SCD-SS and healthy subjects by 12 weeks, deficient (<20 ng/mL) vit D status was eliminated only in those receiving 7000 IU/d. For subjects with SCD-SS, by 12 weeks there was a significant (all P<0.05) increase in fetal hemoglobin, decrease in high-sensitivity C-reactive protein, and reduction in the percentage of subjects with a high platelet count.

[Vitamin D in children and adolescents with sickle cell disease: an integrative review]

Objective:

To review the literature about the prevalence of vitamin D deficiency and its consequences in children and adolescents with sickle-cell disease.

Data sources:

The literature survey was performed through the bibliographic databases MEDLINE; U.S. National Library of Medicine and National Institutes of Health (PubMed); Literatura Latino-Americana e do Caribe em Ciências da Saúde (Lilacs), and the Cochrane Library. The keywords were selected using Medical Heading Terms (MeSH): “vitamin D” OR “vitamin D deficiency” AND “anemia, sickle cell” AND “child” AND “adolescent”. The search was limited to articles in English, Spanish and Portuguese, published until April 2014.

Data synthesis:

Eleven articles were selected among the 18 found. In 6 of the 11 studies, serum levels of vitamin D in children and/or adolescents with sickle-cell anemia were low. The prevalence of vitamin D deficiency in patients with sickle-cell anemia exceeded that of the comparison group. The low intake of vitamin D, seasonality, exposure to sun, increased metabolism associated with the hemoglobinopathy, and age increase were factors associated with the deficiency. There was an association between a significant vitamin D deficiency and bone weakness and painful crises. There was a positive correlation between increased levels of vitamin D by supplementation and functional, physical capacity.

Conclusions:

The vitamin D deficiency in children and adolescents with sickle-cell disease is prevalent and requires further studies to demonstrate its association with comorbidities and possible benefits of vitamin D supplementation.

Vitamin D deficiency and acute vaso-occlusive complications in children with sickle cell disease

BACKGROUND

Vitamin D is increasingly recognized for its roles in non-skeletal disorders. Patients with sickle cell disease (SCD) have a high prevalence of vitamin D deficiency but data are limited with respect to possible associations between low vitamin D and acute vaso-occlusive complications. We examined whether vitamin D deficiency is associated with acute pain and acute chest syndrome (ACS) in children with SCD.

PROCEDURE

A cross-sectional study was conducted in 95 children with SCD who had serum 25-hydroxyvitamin D (25-OHD) measured during comprehensive care examinations. History of acute pain and ACS within two years of obtaining 25-OHD was collected. Associations between 25-OHD levels and acute vaso-occlusive events were analyzed by logistic regression. Odds ratios and 95% confidence intervals were calculated for the risk of pain and ACS associated with vitamin D deficiency (25-OHD <20 ng/ml).

RESULTS

Subjects were 3-20 years old (median 10.6); 48 males, 47 females; 46 African, 49 Hispanic; 72 SS, 20 SC, 1 S/β(0) Thalassemia, and 2 S/β(+) Thalassemia. Median 25-OHD was 16 ng/ml. Fifty-six (59%) were vitamin D-deficient. Thirty-one (33%) and 29 (31%) had at least one episode of pain and ACS, respectively. Serum 25-OHD was significantly associated with pain (P = 0.0121) but not with ACS (P = 0.628). Of those with pain, 73% (23/31) were vitamin D-deficient while 26% (8/31) had 25-OHD ≥20 ng/ml (P = 0.04, OR = 2.7, 95%CI = 1.05-6.94).

CONCLUSIONS

Our findings emphasize the high prevalence of vitamin D deficiency and its potential association with acute pain in SCD. Correcting low vitamin D may offer a simple, low-cost intervention to help reduce acute vaso-occlusive complications.

Prevalence of vitamin D deficiency in sickle cell disease: a systematic review

Vitamin D deficiency has emerged as a public health focus in recent years and patients with sickle cell disease (SCD) reportedly have a high prevalence of the condition. Our objectives were to summarize definitions of vitamin D deficiency and insufficiency used in the literature, and to determine the prevalence and magnitude of each in patients with SCD through a systematic review conducted according to PRISMA guidelines. From a PubMed search, 34 potential articles were identified and 15 met eligibility criteria for inclusion. Definitions of deficiency and insufficiency varied greatly across studies making direct comparisons difficult. This review provides evidence to suggest that suboptimal vitamin D levels are highly prevalent among those with SCD, far more so than in comparable non-SCD patients or matched control populations. Defining deficiency as vitamin D <20ng/mL, prevalence estimates in SCD populations range from 56.4% to 96.4%. When compared with results from the population-based National Health and Nutrition Examination Survey, however, the general African American population appeared to have a similarly high prevalence of vitamin D deficiency. African American patients with and without SCD were both substantially higher than that of Caucasians. What remains to be determined is whether there are adverse health effects for patients with SCD because of concurrent vitamin D deficiency.

Vitamin D levels are low in adult patients with sickle cell disease in Jamaica and West Africa

Background

Patients with sickle cell disease in the USA have been noted to have lower levels of vitamin D – measured as 25-hydroxyvitamin D (25(OH)D) – compared to controls. Average serum 25(OH)D levels are also substantially lower in African Americans than whites, while population distributions of 25(OH)D among Jamaicans of African descent and West Africans are the same as among USA whites. The purpose of this study was to examine whether adult patients with sickle cell disease living in tropical regions had reduced 25(OH)D relative to the general population.

Methods

We analyzed serum 25(OH)D in stored samples collected from studies in Jamaica and West Africa of adult patients with sickle cell disease and adult population controls.

Results

In samples of 20 Jamaicans and 50 West Africans with sickle cell disease mean values of 25(OH)D were 37% and 39% lower than controls, respectively. Metabolic abnormalities in the absorption and conversion pathways are possible causes for the consistent relative deficiency of 25(OH)D in sickle cell disease.

Conclusions

Low 25(OH)D levels in tropical Africa where the burden of sickle cell disease is highest, deserve further investigation, and a randomized trial is warranted to address efficacy of supplementation.

Bone mineral density patterns in vitamin D deficient African American men with sickle cell disease

OBJECTIVE

To describe bone mineral density (BMD) patterns by densitometry in adult African American (AA) men with sickle cell disease (SCD) who are vitamin D deficient (Vit DD).

INCLUSION/EXCLUSION CRITERIA

All SCD phenotypes were eligible. Those with chronic renal failure or hyperparathyroidism were excluded.

DATA COLLECTION

Demographics, body mass index and SCD genotype.

LABORATORY

Albumin, ferritin, calcium, phosphorus, 25-hydroxy vitamin D and intact-parathyroid hormone were obtained. BMD, T and Z scores: T scores at the lumbar spine were used to categorize normal, osteopenia and osteoporosis based on World Health Organization criteria.

STATISTICAL ANALYSES

Mean ± standard deviation was used to describe continuous data, whereas categorical data were described by counts and percentages. The χ test was used to analyze categorical variables; Student's t test or one-way analysis of variance, when appropriate, was used to compare continuous variables. Rates of osteopenia-osteoporosis were determined, and the parameter with 95% confidence interval (CI) of a proportion was constructed. All tests were 2-sided, and a P ≤ 0.05 was considered statistically significant. We used StatView Version 5.01 (SAS institute Inc, Cary, NC) for the statistical analysis.

RESULTS

Seventy-eight AA men with SCD disease and Vit DD were enrolled in this study. We found that 42% of the men studied had low-BMD (osteopenia or osteoporosis) using T scores at the lumbar spine to establish densitometry strata. The prevalence of osteoporosis was 14%.

CONCLUSIONS

A large proportion of adult AA men with SCD and Vit DD showed low BMD.

Effect of prophylactic vitamin D on anesthetic outcome in children with sickle cell disease

Background:

Few previous studies proved that complications related to sickle cell disease (SCD) were common with regional anesthesia compared with general anesthesia while others reported no differences. This study was carried out to evaluate the role of prophylactic vitamin D on anesthetic outcome among male children with SCD undergoing circumcision.

Materials and Methods:

A comparative study was carried out on 58 children undergoing circumcision with the regional block under light general anesthesia. The study sample was classified into two groups: one group received daily 400 IU vitamin D for 6 months before surgery while the other group without vitamin D. All patients were followed regarding the post-operative analgesia and the incidence of post-operative SCD related complications (acute chest syndrome, painful crisis and cerebrovascular accident). Data were analyzed with Statistical Package for Social Sciences version 13, produced by IBM SPSS, Inc. in Chicago, Illinois, USA.

Results:

There was a highly significant difference between the two groups (P < 0.001) regarding first analgesic request and total analgesic consumption per day: there was delayed analgesic request and less total analgesic consumption per day in vitamin D group. Comparison of post-operative sedation scores showed highly significant difference (P < 0.001) between the two groups, Sedation scores was increased significantly in vitamin D group. This study also reported that the administration of vitamin D was associated with less noticeable post-operative SCD complications.

Conclusion:

The use of prophylactic vitamin D in SCD will result in delayed post-operative analgesic request and less total analgesic requirement. Administration of vitamin D was also associated with less post-operative complications.

The association of transfusion status with antioxidant enzymes and malondialdehyde level in Nigerians with sickle cell disease

BACKGROUND

Sickle cell disease (SCD) often leads to chronic hemolytic anemia of varying severity, and blood transfusion may be employed in the management of SCD complications.

OBJECTIVE

The aim of the study was to evaluate the effect of blood transfusion on the activities of some antioxidant enzymes as well as lipid peroxide and to relate transfusion status to these enzymes and malondialdehyde (MDA) in SCD patients.

MATERIALS AND METHODS

Glutathione peroxidase (GPX), superoxide dismutase, catalase, MDA, and lipoproteins were assayed in 87 SCD and 20 age- and sex-matched subjects with normal hemoglobin. Of the 87 SCD patients, 30 had multiple transfusions, 21 had been transfused once while 36 had not been transfused within the last 3 months.

RESULTS

Statistically significant decrease in the mean levels of GPX (P = 0.045) and Cu/Zn SOD (P = 0.001) and increased (P = 0.001) MDA were observed in the transfused compared to non-transfused patients. Similarly, significant decrease (P = 0.001) in Cu/Zn SOD and increase (P = 0.01) in MDA were observed in multi transfused compared to those who had been transfused once. Transfusion status correlated (P <0.047) inversely with Cu/Zn SOD and positively with MDA.

CONCLUSION

Reduced activity levels of serum antioxidant enzymes and increased mean levels of MDA were observed in transfused compared to non-transfused SCD patients and these changes correlated with transfusion status.

TNF-α, IFN-γ, IL-10, and IL-4 levels were elevated in a murine model of human sickle cell anemia maintained on a high protein/calorie diet

Increased frequency and risk of infection is one of the well described complications of sickle cell anemia (SCA). Dietary supplementation in children with SCA and growth retardation improved growth and decreased incidence of infection. We investigated the impact of a high protein diet on weight gain, hematological profile, and immune cytokine levels in the Berkeley model of SCA, 16 of which were randomized to either regular mouse diet with 20% of calories from protein (n = 8) or a test feed with 35% of calories from protein (n = 8). Control mice (C57BL/6, n = 16) were correspondingly randomized, and were all feed ad libitum for three months with actual intake estimated by subtracting the weight of gnaw waste from that of the feed given. Blood was collected at sacrifice by cardiac puncture and plasma levels of T helper cell 1 (TH1) and TH2 associated cytokines were measured using a multiplex antibody immobilized bead assay. SCA mice receiving the 35% protein diet had modest improvements in weight, red blood cell count, and hemoglobin level, with a slight decrease in reticulocyte count compared with SCA mice on the regular mouse diet. Furthermore, they also had significantly higher plasma levels of cytokines tumor necrosis factor (TNF)-α (P = 0.02), interferon (IFN)-γ (P = 0.01), interleukin 10 (IL-10; P = 0.02), and IL-4 (P = 0.02) compared with those that received the 20% protein diet. We conclude that providing additional protein calories to transgenic SCA mice increased the plasma levels of acute inflammatory cytokines associated with immune response to infection, which might partly explain decreased episodes of infection observed among supplemented children with SCA.

A review on vitamin d deficiency treatment in pediatric patients

Vitamin D is essential for calcium absorption and for maintaining bone health in the pediatric population. Vitamin D deficiency may develop from nutritional deficiencies, malabsorption, enzyme-inducing medications, and many other etiologies. It may present as hypocalcemia before bone demineralization at periods of increased growth velocity (infancy and adolescence) because the increased calcium demand of the body cannot be met. In children, inadequate concentrations of vitamin D may cause rickets and/or symptomatic hypocalcemia, such as seizures or tetany. In this review, we will discuss the pharmacology behind vitamin D supplementation, laboratory assessments of vitamin D status, current literature concerning vitamin D supplementation, and various supplementation options for the treatment of vitamin D deficiency in the pediatric population.

Considerations for Care: Management of Asthma in the Child with Sickle Cell Disease

Asthma is difficult to diagnose in the child with sickle cell disease because symptoms and pulmonary function abnormalities are similar to the spectrum of pulmonary manifestations in sickle cell disease. There are no published reports of controlled trials of asthma medications in children with sickle cell disease. Thus, treatment decisions should be guided by the Expert Panel Report 3: Guidelines for the Diagnosis and Management of Asthma (www.nhlbi.nih.gov/guidelines/asthma/asthgdln.pdf). However, issues specific to children with sickle cell disease should be considered. Initial strategies should focus on control of environmental triggers, as effectiveness on asthma outcomes is proven and the cost for implementation can be low. Use of short- and long-acting β₂-agonists may prolong QTc, particularly in this population of children who already have a higher prevalence of prolonged QTc than the general population. Long-acting β₂-agonist use has been associated with life-threatening asthma exacerbations with potentially higher risks in African Americans. Montelukast has been reported to increase suicidal thinking and behavior, and persons with asthma and sickle cell disease are already at risk for these events. Oral corticosteroids in the treatment of acute chest syndrome may increase risk of readmission even in children with asthma. The lack of prospective controlled trials of asthma drug treatment in children with asthma and sickle cell disease compels us to move this issue forward.

Relationship between vitamin D deficiency and bone fragility in sickle cell disease: a cohort study of 56 adults

BACKGROUND

Recent studies suggest that patients with sickle cell disease (SCD) have profound vitamin D (VD) deficiency. Limited data exist on the effect of VD deficiency on bone fragility in these patients.

OBJECTIVES

To assess the prevalence of VD deficiency in adults with SCD and its consequences on bone metabolism and fragility.

METHODS

This prospective study included 56 SCD adult patients (mean age 29.8 ± 9.5 years), in a clinically steady state. Clinical and laboratory data were recorded. Bone mineral density (BMD) was measured using dual X-ray absorptiometry. Fracture history, BMD, avascular osteonecrosis, H-shaped vertebra and markers of mineral metabolism were compared between two groups of patients presenting very low (≤ 6 ng/mL, n=26) (group 1) and low (>6 ng/mL, n=26) (group 2) 25(OH)D concentration, respectively.

RESULTS

Median 25(OH)D concentration was 6 ng/mL. VD deficiency (25(OH)D <10 ng/mL) was found in 42 out of 56 patients (75%) and secondary hyperparathyroidism in 40 (71.4%). History of fracture was documented in 17 patients (30.3%), osteopenia and/or osteoporosis in 39.6% of patients. Overall, patients of group 1 were more likely to have sustained a fracture (42.8%) compared to patients of group 2 (17.8%) (p=0.04). These patients had also lower body mass index and significantly higher parathyroid hormone, C-terminal telopeptides of type I-collagen and bone-specific alkaline phosphatase serum levels. There was no difference between group for BMD, avascular osteonecrosis history, H-shaped vertebra, and disease severity markers.

CONCLUSION

This study suggests that VD deficiency is a key feature in SCD-bone disease. It is highly prevalent and associated with hyperparathyroidism, bone resorption markers, and history of fracture. The optimal supplementation regimen remains to be determined.

Status of vitamin D in children with sickle cell disease living in Madrid, Spain

Patients with sickle cell disease have vitamin D deficiency and poor bone health which makes them prone to have an increased risk of fractures and osteoporosis in adulthood. We performed a prospective, cross-sectional study in children diagnosed with sickle cell disease living in Madrid, Spain. The purpose of this study was to evaluate the status of vitamin D of these children. Patients 0-16 years old were enrolled between 2008 and 2011. We studied demographics, calcium metabolism, and bone health, especially by measuring levels of 25-hydroxyvitamin D (25(OH)D), during different seasons of the year, and bone densitometry (beyond 4 years of age). Seventy-eight children were included in the study. Mean age was 4.8 ± 4.3 years, and mean serum 25(OH)D level was 21.50 ± 13.14 ng/ml, with no differences in 25(OH)D levels within different seasons. Fifty-six percent of children had levels of 25(OH) vitamin D of <20 ng/ml, whereas 79 and 18 % of them had levels of <30 and <11 ng/ml, respectively. Secondary hyperparathyroidism was observed in 25 % of children. Densitometry was performed in 33 children, and an abnormal z-score was seen in 15.2 % of them with no correlation with levels of 25(OH)D.

CONCLUSIONS

Vitamin D deficiency is highly prevalent in children with sickle cell disease, who are residing in Madrid, Spain, and it is detected at a young age. We propose that early intervention may increase the possibility of an adequate bone density later in life.

Vitamin D concentrations among healthy children in Calgary, Alberta

OBJECTIVE

To examine the relationship between serum vitamin D concentrations, dietary intake and body mass index among healthy children living in Calgary, Alberta.

METHODS

The present cross-sectional study included healthy children two to 13 years of age who presented to the Alberta Children's Hospital for elective surgery during a 12-month period. Data including the child's weight, height, age, sex, ethnicity, dietary intake, use of vitamin supplements, physical activity and time spent outdoors were collected. Serum concentrations of 25-hydroxyvitamin D (25[OH]D) were measured using commercial immunoradiometric assay kits.

RESULTS

Serum 25(OH)D concentrations were available for 1442 of 1862 participants, of whom 862 (59.8%) were boys. The mean (± SD) serum 25(OH)D concentration was 86.1±35.1 nmol/L (range 10 nmol/L to 323 nmol/L). Five hundred thirty-nine (37.4%) participants had insufficient vitamin D status (25[OH]D between 25 nmol/L and lower than 75 nmol/L), and vitamin D deficiency (25[OH]D 25 nmol/L or lower) was present in 29 subjects (2.0%). Children in the older age group (nine to 13 years) were more likely to have suboptimal vitamin D (P<0.001). Other risk factors significantly associated with suboptimal vitamin D status included overweight or obesity, nonwhite ethnicity, winter months, dietary vitamin D intake of less than 200 IU/day and less time spent outdoors.

CONCLUSION

A high rate of suboptimal vitamin D concentrations was observed among the participants. Beyond promoting a vitamin D-enriched diet, physicians should also consider the body mass index and other risk factors to determine the optimal vitamin D intake for children living in the area studied.

Vitamin D deficiency and comorbidities in children with sickle cell anemia

Vitamin D deficiency is known to be common among patients with sickle cell anemia (SCA). Vitamin D levels were measured in 139 children (aged 7.9 to 15.1 years) to study its association with SCA morbidities; severe deficiency <10 ng/mL was present in 64.0% and only 2.2% were sufficient (>30 ng/mL). Vitamin D levels were associated with pulmonary function (forced expiratory volume in 1 second [FEV(1)]), but not associated with either rates of acute pain or acute chest syndrome episodes. Further studies are needed to be able to compare outcomes in those with deficiency to those with sufficiency, as well as to treating patients with SCA with vitamin D to better establish a possible link, if any, between vitamin D and SCA morbidity.

Asthma in sickle cell disease: implications for treatment

Objective. To review issues related to asthma in sickle cell disease and management strategies. Data Source. A systematic review of pertinent original research publications, reviews, and editorials was undertaken using MEDLlNE, the Cochrane Library databases, and CINAHL from 1947 to November 2010. Search terms were [asthma] and [sickle cell disease]. Additional publications considered relevant to the sickle cell disease population of patients were identified; search terms included [sickle cell disease] combined with [acetaminophen], [pain medications], [vitamin D], [beta agonists], [exhaled nitric oxide], and [corticosteroids]. Results. The reported prevalence of asthma in children with sickle cell disease varies from 2% to approximately 50%. Having asthma increases the risk for developing acute chest syndrome , death, or painful episodes compared to having sickle cell disease without asthma. Asthma and sickle cell may be linked by impaired nitric oxide regulation, excessive production of leukotrienes, insufficient levels of Vitamin D, and exposure to acetaminophen in early life. Treatment of sickle cell patients includes using commonly prescribed asthma medications; specific considerations are suggested to ensure safety in the sickle cell population. Conclusion. Prospective controlled trials of drug treatment for asthma in patients who have both sickle cell disease and asthma are urgently needed.

Understanding Growth Failure in Children With Homozygous Sickle-Cell Disease

Sickle-cell disease is the most prevalent genetic hematologic condition in the United States. Numerous studies have demonstrated poor growth and delayed maturation in children with homozygous sickle-cell disease; however, the pathophysiology remains inadequately understood. Affected children have normal weight and length at birth, and then around 6 months of age their growth patterns begin to diverge from the norm. The growth deficits experienced by these children remain a problem with clinical significance and intangible consequences. A review of literature has provided insight into the multifactorial basis of the growth failure experienced by this population. It is important that nurses and health care providers are familiar with the growth patterns unique to sickle-cell disease and recognize their role in clinical practice.

Prevalence of vitamin D deficiency in adults with sickle cell disease

Vitamin D deficiency has been linked to fracture risk and chronic musculoskeletal pain. Adults with sickle cell disease have a high prevalence of low bone density and chronic pain with poorly defined etiologies. We recognized that vitamin D deficiency may represent a treatable etiology and sought to determine the prevalence of vitamin D deficiency in adults with sickle cell. We measured 25-hydroxy vitamin D levels in adults at 2 university-based sickle cell disease-management programs. Regression was performed in 142 patients to identify predictors of low vitamin D. Mean vitamin D levels were 9.0 ng/mL at Eastern Virginia Medical School and 12.8 ng/mL at University of Chicago; 139 of 142 (98%) had suboptimal levels (<30 ng/mL) and 85/142 (60%) were severely deficient (<10 ng/mL). Vitamin D level was not related to age, sex, hydroxyurea use, sickle cell type, or date of lab draw. Vitamin D deficiency was, therefore, nearly ubiquitous in our patient population, with a majority being severely deficient. Further studies are warranted to evaluate the effects of vitamin D repletion on clinical outcomes such as bone density, chronic musculoskeletal pain, and functional status. Clinicians caring for patients with sickle cell disease should be aware of and screen for this important clinical state.

The Role of Nutrition in Sickle Cell Disease

Finding a widely available cure for sickle cell anemia (HbSS) still remains a challenge one hundred years after its discovery as a genetically inherited disease. However, growing interest in the nutritional problems of the disease has created a body of literature from researchers seeking nutritional alternatives as a means of decreasing morbidity and improving quality of life among HbSS patients. This review demonstrates that over the past 30 years the role of protein/energy deficiency in HbSS has been more clearly defined via direct measurements, leading to the concept of a relative shortage of nutrients for growth and development, despite apparently adequate dietary intakes. Although there is still a paucity of data supporting the efficacy of macronutrient supplementation, it is becoming clearer that recommended dietary allowances (RDAs) for the general population are insufficient for the sickle cell patient. A similar shortage is likely to be true for micronutrient deficiencies, including recent findings of vitamin D deficiency that may be associated with incomplete ossification and bone disease, which are well known complications of HbSS disease. We conclude that there is need for more effort and resources to be dedicated to research (including supplementation studies of larger sample size) aimed at establishing specific RDAs for HbSS patients, much like the specific RDAs developed for pregnancy and growth within the general population.

The recognition and treatment of growth disorders - a 50-year retrospective

The past 50 years have seen great progress in the understanding and treatment of classic growth disorders. Advances such as the recognition of hormone receptor defects, the development of recombinant growth hormone, and the expanding awareness of epigenetic phenomena affecting growth are among these great achievements. Yet growth failure remains a pervasive problem among children with complex health conditions, such as survivors of childhood cancers, premature infants, organ transplant recipients, and children with cystic fibrosis. The significant increases in life expectancy among these groups underscores the potential consequences of poor growth, whether due to the underlying conditions or medical treatments, as they may have long-lasting effects into adulthood. The ongoing contributions of human biologists to the study of human growth remain essential in the recognition and treatment of growth disorders, by defining normal patterns of growth and body composition, the interplay of growth and maturation, the role of environmental, behavioral and genetic factors, and the long-term consequences of growth patterns. Examples will be given based on two common genetic disorders, cystic fibrosis and sickle-cell anemia, to highlight the relationships between growth failure, survival, and malnutrition. Also, a study of bone mineral accretion in children with cystic fibrosis will illustrate the importance of understanding patterns of growth in healthy children, and their application in the diagnosis and management of children with chronic disease. These examples accentuate the need for continued participation of human biologists in the study of growth and development and the care of children.

Nutritional deficiencies in iron overloaded patients with hemoglobinopathies

One of the hallmarks of both sickle cell disease (SCD) and thalassemia major (TM) is accelerated oxidative damage. Decreased antioxidant levels and increased oxidant stress biomarkers are found in both diseases. Although isolated vitamin deficiencies have been reported in TM and nontransfused SCD patients, a comprehensive evaluation of vitamin and trace mineral levels has never been performed in chronically transfused SCD or TM patients. As vitamins and trace minerals may be consumed as a result of chronic oxidative stress; we hypothesized that levels of these compounds would correlate with surrogates of iron overload, hemolysis, and inflammation in chronically transfused patients. Using a convenience sample of our group of chronically transfused patients we studied 43 patients with SCD (17 male, 26 female) and 24 patients with TM (13 male and 11 female). The age range for our patients varied from 1.5 to 31.4 years. Levels of vitamins A, thiamin, B6, B12, C, D, E as well as selenium, zinc, copper, and ceruloplasmin were measured. We found that 40-75% of the patients were deficient in A, C, D and selenium and 28-38% of the patients had low levels of B vitamins and folate. There was little association with iron overload, hemolysis, or inflammation. Although the precise mechanism of these deficiencies is unclear, they may contribute to the morbidity of chronically transfused hemoglobinopathy patients.

Growth and nutritional status of children with homozygous sickle cell disease

BACKGROUND

Poor growth and under-nutrition are common in children with sickle cell disease (SCD). This review summarises evidence of nutritional status in children with SCD in relation to anthropometric status, disease severity, body composition, energy metabolism, micronutrient deficiency and endocrine dysfunction.

METHODS

A literature search was conducted on the Medline/PUBMED, SCOPUS, SciELO and LILACS databases to July 2007 using the keywords sickle cell combined with nutrition, anthropometry, growth, height and weight, body mass index, and specific named micronutrients.

RESULTS

Forty-six studies (26 cross-sectional and 20 longitudinal) were included in the final anthropometric analysis. Fourteen of the longitudinal studies were conducted in North America, the Caribbean or Europe, representing 78.8% (2086/2645) of patients. Most studies were observational with wide variations in sample size and selection of reference growth data, which limited comparability. There was a paucity of studies from Africa and the Arabian Peninsula, highlighting a large knowledge gap for low-resource settings. There was a consistent pattern of growth failure among affected children from all geographic areas, with good evidence linking growth failure to endocrine dysfunction, metabolic derangement and specific nutrient deficiencies.

CONCLUSIONS

The monitoring of growth and nutritional status in children with SCD is an essential requirement for comprehensive care, facilitating early diagnosis of growth failure and nutritional intervention. Randomised controlled trials are necessary to assess the potential benefits of nutritional interventions in relation to growth, nutritional status and the pathophysiology of the disease.

High risk of vitamin D deficiency in children with sickle cell disease

Vitamin D is a particularly concerning nutrient for children with homozygous SS sickle cell disease (SCD-SS) due to their increased skin melanin concentrations, reduced levels of physical activity, and poor vitamin D intake. The goal of this study was to compare the vitamin D status of children with SCD-SS to healthy African-American children living in the same geographic area. Growth, dietary intake, serum 25-hydroxyvitamin D [25(OH)D], and intact parathyroid hormone (iPTH) concentrations were measured in 61 African-American subjects with SCD-SS and 89 healthy African-American control subjects age 5 to 18 years from the Philadelphia, PA, region (latitude 39.95 degrees N). Median serum 25(OH)D concentrations were 15 ng/mL (95% confidence interval [CI]: 13, 17) in subjects with SCD-SS and 21 ng/mL (95% CI: 18, 22) in healthy control subjects (P<0.0002). Vitamin D deficiency [25(OH)D<11 mg/mL] was found in 33% of subjects with SCD-SS and 9% of healthy control subjects (P<0.001); 25% of subjects with SCD-SS and 17% of healthy control subjects had elevated iPTH [(>59 rhog/mL), P<0.05]. Ninety-three percent of subjects with SCD-SS and 90% of healthy subjects had vitamin D insufficiency [25(OH)D<30 mg/mL]. The risk of vitamin D deficiency among subjects with SCD-SS was 5.3 (95% CI: 2.5, 8.2) times greater than control subjects, adjusted for season and age. Poor vitamin D status was prevalent in children with SCD-SS and healthy African-American children living in the same geographic area. However, children with SCD-SS were at greater risk for vitamin D deficiency than healthy African-American children.