Nocturnal hypoxaemia is common in adults with sickle cell anaemia.

The symptoms and sequelae of sickle cell anaemia (SCA) are caused by the polymerization of deoxygenated sickle haemoglobin, and people with SCA may be uniquely susceptible to adverse outcomes from hypoxia and haemoglobin desaturation. We examined by oximetry adults (aged 18-45 years) with SCA presenting symptoms indicative of polysomnography, at a single institution, irrespective of treatment, for nocturnal hypoxaemia. Clinical labs and blood for in vitro assessments were taken upon enrolment and after 8-12 weeks of oxygen therapy or observation. Of 21 screened participants, nine (43%) had sufficient nocturnal hypoxaemia to warrant oxygen therapy (≥5 min at SpO2 ≤ 88%). Time spent at SpO2 ≤ 88% associated with age (p = 0.0092), annual hospitalizations (p = 0.0018) and anaemia (p = 0.0139), as well as plasma levels of TNFα (p = 0.0019) and IL-4 (p = 0.0147). Longitudinal analysis showed that WBC significantly decreased during the follow-up period in hypoxic individuals but not in non-hypoxic individuals (p = 0.0361 and p = 0.6969 respectively). Plasma levels of CCL2 and IL-1ra tended to increase, while levels of red blood cell reactive oxygen species tended to decrease with oxygen therapy. Overall, nocturnal hypoxaemia was common in this pilot study population and associated with plausible clinical comorbidities; oxygen therapy may decrease inflammation and oxidative damage in hypoxic individuals.

The Danish national haemoglobinopathy screening programme: Report from 16 years of screening in a low-prevalence, non-endemic region.

The Danish national haemoglobinopathy screening programme seeks to determine parental haemoglobinopathy carrier state antenatally. In this retrospective register-based study, we evaluated the 16-year trajectory of this programme, utilising the Danish Red Blood Cell Centre's laboratory database, covering approximately 77% of the Danish population. During the study period, we observed a substantial increase in annual diagnostic examinations performed, from 389 in 2007 to 3030 in 2022. Women constituted 88% of these cases, aligning with the emphasis of the screening programme. Of these, 54% of women of reproductive age (15-40 years) and 10% of women >40 years were specified as pregnant. During our study period, 61 children were born with a severe haemoglobinopathy, out of which 23 children were born from mothers not residing in Denmark during their first trimester thus not included in the screening programme. Prenatal invasive testing was performed for 60 fetuses, identifying 12 with homozygous or compound heterozygous haemoglobinopathy. The Danish haemoglobinopathy screening programme has provided screening, information and reproductive choices for numerous families. During the study period, screening for haemoglobinopathies has been steadily increasing and is expected to continue to increase. Awareness of and adherence to the screening programme is subject of further investigation and optimisation.

The enigma of sickle cell hepatopathy: Pathophysiology, clinical manifestations and therapy.

Sickle cell disease (SCD) is one of the most common genetic disorders in the world predominantly affecting economically disadvantaged populations. There is a notable discrepancy between the growing adult SCD population and available diagnostic and therapeutic interventions for SCD. Sickle cell hepatopathy (SCH) is an all-inclusive term to describe the acute and chronic liver manifestations of SCD. The pathophysiology of SCH follows no defined pattern or sequence that poses challenges to clinicians and researchers alike. Evidence is lacking for this underreported disease at various levels from diagnostic to therapeutic options. This paper reviews the basic pathophysiology, clinical features, biochemical and radiological findings of various SCH manifestations and outlines the management of each condition. Old and new therapy options in SCD including hydroxyurea, red blood cell exchange transfusion, ursodeoxycholic acid, voxelotor, l-glutamine and crizanlizumab have been reviewed to investigate the role of these options in treating SCH. The role of liver transplant, haematopoietic stem cell transplant and gene therapy in SCH patients have been reviewed.

Shift in emergency department utilization by frequent attendees with sickle cell disease during the COVID-19 pandemic: A multicentre cohort study.

While the coronavirus disease-2019 (COVID-19) might have increased acute episodes in people living with sickle cell disease (SCD), it may also have changed their reliance on emergency department (ED) services. We assessed the impact of the COVID-19 pandemic and lockdowns on ED visits in adult SCD people followed in five French reference centres, with a special focus on 'high users' (≥10 visits in 2019). We analysed the rate of ED visits from 1 January 2015 to 31 December 2021, using a self-controlled case series. Among 1530 people (17 829 ED visits), we observed a significant reduction in ED visits during and after lockdowns, but the effect vanished over time. Compared to pre-pandemic, incidence rate ratios for ED visits were 0.59 [95% CI 0.52-0.67] for the first lockdown, 0.66 [95% CI 0.58-0.75] for the second and 0.85 [95% CI 0.73-0.99] for the third. High users (4% of people but 33.7% of visits) mainly drove the reductions after the first lockdown. COVID-19 lockdowns were associated with reduced ED visits. While most people returned to their baseline utilization by April 2021, high users had a lasting decrease in ED visits. Understanding the factors driving the drop in ED utilization among high users might inform clinical practice and health policy.

Left ventricular global longitudinal strain and acute myocardial injury in patients with sickle cell disease admitted to the intensive care unit for vaso-occlusive crisis.

In patients with sickle cell disease (SCD), SCD-related cardiomyopathy may be partly due to repeated ischaemic events related to sickling during vaso-occlusive crises, but few clinical studies support this hypothesis. We evaluated the incidence of acute myocardial ischaemia during vaso-occlusive crises as assessed by the left ventricular global longitudinal strain (LVGLS) and high-sensitive cardiac troponin T (hs-cTnT). We included adult patients with SCD admitted to the intensive care unit (ICU) for vaso-occlusive crisis. We collected hs-cTnT and measured LVGLS with echocardiography at admission (day 1), day 2, day 3 and ICU discharge. Among 55 patients included, considering only the first hospitalization of patients admitted several times, 3 (5%) had elevated hs-cTnT at ≥1 time point of the ICU stay. It was ≤2 times the upper limit of normal in two of these patients. LVGLS was altered at ≥1 time point of the ICU stay in 13 (24%) patients. Both hs-cTnT and LVGLS were abnormal at ≥1 time point of the hospital stay in 2 (4%) patients. Acute myocardial injury as assessed by troponin elevation and LVGLS impairment was a rare event during vaso-occlusive crises.

Association of biomarkers of endothelial function, coagulation activation and kidney injury with persistent albuminuria in sickle cell anaemia.

Persistent albuminuria (PA) is common in sickle cell anaemia (SCA). With the association of chronic kidney disease (CKD) with increased mortality, biomarkers that predict its development or progression are needed. We evaluated the association of select biomarkers with PA in adults with SCA using Kruskal-Wallis rank-sum test and logistic regression models, with adjustment for multiple testing. Of 280 subjects, 100 (35.7%) had PA. Median plasma levels of soluble vascular cell adhesion molecule-1 (VCAM-1) (1176.3 vs. 953.4 ng/mL, false discovery rate [FDR] q-value <0.003), thrombin-antithrombin complex (5.5 vs. 4.7 ng/mL, FDR q-value = 0.04), and urinary angiotensinogen (AGT) (12.2 vs. 5.3 ng/mg, FDR q-value <0.003), urinary nephrin (30.6 vs. 27.2 ng/mg, FDR q-value = 0.04), and urinary kidney injury molecule-1 (KIM-1) (0.8 vs. 0.5 ng/mg, FDR q-value <0.003), normalized to urine creatinine, were significantly higher in subjects with PA. In multivariable analysis, only urinary AGT (odds ratio = 1.058, FDR q-value <0.0001) remained a significant predictor of PA. In addition, soluble VCAM-1 (FDR q-value <0.0001), D-dimer (FDR q-value <0.0001), urinary AGT (FDR q-value <0.0001), KIM-1 (FDR q-value <0.0001), and nephrin (FDR q-value <0.0001) were significantly associated with urine albumin-creatinine ratio in multivariable analyses. Longitudinal studies to evaluate the predictive capacity of biomarkers for the development and progression of CKD in SCA are warranted.

Persistent albuminuria and chronic kidney disease in adults with sickle cell anaemia: Results from a multicenter natural history study.

Clinical and laboratory correlates of chronic kidney disease (CKD) in sickle cell anaemia remain incompletely defined. In a multicenter cohort study, we evaluated the prevalence of persistent albuminuria (PA) and characteristics associated with PA, albumin-creatinine ratio (ACR) and decreased estimated glomerular filtration rate (eGFR) using logistic, linear and multinomial regression models, respectively. Of 269 participants (median age: 30 years; 57.2% females), the prevalence of PA was 35.7%. Using baseline ACR values of <100 and ≥100 mg/g, the probabilities of PA were 30.0% and 94.6%, respectively. In multivariable logistic regression analyses, male sex (ß = 0.80 [SE = 0.36], p = 0.024) and ACE inhibitors/ARBs use (ß = 1.54 [SE = 0.43], p < 0.001) were associated with higher likelihoods of PA, while higher haemoglobin (ß = -0.33 [SE = 0.13], p = 0.009) and HbF (ß = -0.04 [SE = 0.02], p = 0.041) were associated with lower likelihoods of PA. In multivariable multinomial regression analyses, older age (ß = 0.06 [SE = 0.02], p = 0.004) and higher alkaline phosphatase (ß = 0.01 [SE = 0.00], p = 0.004) were associated with higher odds of having eGFR 60-90 versus eGFR>90 mL/min/1.73 m2 using the cystatin C-based CKD-EPI-2012 equation. Additionally, higher systolic blood pressure (ß = 0.11 [SE = 0.03], p = 0.001) and blood urea nitrogen (ß = 0.45 [SE = 0.12], p < 0.001) were associated with higher odds, while higher haemoglobin (ß = -1.22 [SE = 0.43], p = 0.004) was associated with lower odds of having eGFR<60 versus eGFR>90 mL/min/1.73 m2. PA and decreased eGFR are associated with measures of disease severity and comorbid conditions (Clinicaltrials.gov Identifier: NCT03277547).

Sickle cell anaemia control mission: Implementation of a comprehensive care model in Anuppur, Madhya Pradesh.

Background & objectives Sickle cell disease (SCD) is a common genetic disorder, predominantly found in the tribal population of India. The examples of models providing comprehensive care and management to individuals with SCD in public health facilities are sparse. The Sickle Cell Anaemia Control Mission is one such model implemented by Jan Swasthya Sahyog, a non-profit organization in collaboration with the National Health Mission in the Anuppur district of Madhya Pradesh. This article aimed to identify the key learnings from this programme that can guide the public health system strengthening with respect to SCD. Methods The Sickle Cell Anemia Control Mission Programme included door to door screening for anaemia, SCD and blood group. SCD cases were included in the programme and other individuals with Anemia were referred for further care. Care for individuals with SCD included counselling, provision of hydroxyurea, regular follow up of clinical parameters and management of complications. Care for individuals with SCD was provided through monthly patient support group (PSG) meetings and regular outpatient /in-patient care at public health facilities. Quantitative data on programme design, screening and patient management collected during programme implementation were used for analysis. Results A total of 39421 persons were screened in 18 months (August 2018-March 2020). Of these 81.9 per cent persons were anaemic, 16.9 per cent had sickle cell trait and 779 (1.98%) had SCD. Eighty-six already diagnosed individuals joined the programme for care. People from all caste categories were diagnosed with SCD. Out of 865 individuals with SCD, 157 underwent regular 9-11 months follow up and showed improvement in clinical symptoms and drug compliance. Interpretation & conclusions Central India has a significant burden of anaemia and SCD. This study found that SCD is present in non-tribals as well. PSGs are an efficient way to deliver non-emergency care for chronic diseases such as SCD.

Acute kidney injury is more common in hospitalised children with sickle cell anaemia in Africa.

AIM: To document the prevalence, severity, hospital outcome and factors associated with acute kidney injury (AKI) in hospitalised children with sickle cell anaemia (SCA). METHODS: In this prospective observational study involving children aged 0.5-17 years with SCA requiring hospitalisation, we used serum creatinine level at 0 and 48 h of hospitalisation to determine the presence of AKI. RESULTS: The study involved 155 children with SCA aged 0.5-17 years with a median (interquartile range) age of 7.8 (4.3-11.0) years. Acute kidney injury occurred in 27 (17.4%) children with 33.3% reaching stage 3. Hepatomegaly (81.5% vs. 55.4%; p = 0.015), splenomegaly (33.3% vs. 10.9%; p = 0.003), dipstick proteinuria (22.2% vs. 5.4%; p = 0.004), and hematuria (29.6% vs. 3.1%; p = <0.001) were more common in those with AKI. In contrast, children with AKI had lower haematocrit (16.9% vs. 22.2%; p = <0.001) and serum bicarbonate (16.7 vs. 19.1 mmoL/L; p = 0.010) compared with those without AKI. Those with AKI had longer hospital stay (median [interquartile range]: 7 [4-12] days vs. 4 [3-6] days; p = 0.008). CONCLUSION: AKI is common among hospitalised children with AKI and is associated with longer hospital stay.

Provider prescription of hydroxyurea in youth and adults with sickle cell disease: A review of prescription barriers and facilitators.

Sickle cell disease (SCD) is an inherited red blood cell disorder associated with frequent painful events and organ damage. Hydroxyurea (HU) is the recommended evidence-based treatment of SCD. However, among patients eligible for HU, prescription rates are low. Utilizing a scoping review approach, we summarized and synthesized relevant findings regarding provider barriers and facilitators to the prescription of HU in youth and adults with SCD and provided suggestions for future implementation strategies to improve prescription rates. Relevant databases were searched using specified search terms. Articles reporting provider barriers and/or facilitators to prescribing HU were included. A total of 10 studies met the inclusion criteria. Common barriers to the prescription of HU identified by providers included: doubts around patients' adherence to HU and their engaging in required testing, concerns about side effects, lack of knowledge, cost and patient concerns about side effects. Facilitators to the prescription of HU included beliefs in the effectiveness of HU, provider demographics and knowledge. Findings suggest significant provider biases exist, particularly in the form of negative perceptions towards patients' ability to adhere to taking HU and engaging in the required follow-up. Improving provider knowledge and attitudes towards HU and SCD may help improve low prescription rates.

Current developmental screening practices in young children with sickle cell disease.

Despite recent developmental screening guidelines, rates of neurodevelopmental disorders (NDDs) remain lower than expected in children with sickle cell disease (SCD). A retrospective chart review identified 276 eligible patients; 214 charts were available for developmental screening and 207 charts for autism-specific screening. Developmental surveillance/screening was conducted in 70% of charts and autism-specific screening in 19% of charts. Validated tools were used in 32% of developmental screenings and 92% of autism-specific screenings. Many children (57%) were screened outside recommended ages. In conclusion, children with SCD are not regularly receiving appropriate developmental screening and surveillance by their healthcare providers.

Association of haemolysis markers, blood viscosity and microcirculation function with organ damage in sickle cell disease in sub-Saharan Africa (the BIOCADRE study).

Sickle cell anaemia (SCA) is a monogenic disease with a highly variable clinical course. We aimed to investigate associations between microvascular function, haemolysis markers, blood viscosity and various types of SCA-related organ damage in a multicentric sub-Saharan African cohort of patients with SCA. In a cross-sectional study, we selected seven groups of adult patients with SS phenotype in Dakar and Bamako based on the following complications: leg ulcer, priapism, osteonecrosis, retinopathy, high tricuspid regurgitant jet velocity (TRV), macro-albuminuria or none. Clinical assessment, echocardiography, peripheral arterial tonometry, laboratory tests and blood viscosity measurement were performed. We explored statistical associations between the biological parameters and the six studied complications. Among 235 patients, 58 had high TRV, 46 osteonecrosis, 43 priapism, 33 leg ulcers, 31 retinopathy and 22 macroalbuminuria, whereas 36 had none of these complications. Multiple correspondence analysis revealed no cluster of complications. Lactate dehydrogenase levels were associated with high TRV, and blood viscosity was associated with retinopathy and the absence of macroalbuminuria. Despite extensive phenotyping of patients, no specific pattern of SCA-related complications was identified. New biomarkers are needed to predict SCA clinical expression to adapt patient management, especially in Africa, where healthcare resources are scarce.

Neurofilament light chain: A potential biomarker for cerebrovascular disease in children with sickle cell anaemia.

Cerebrovascular injury frequently occurs in children with sickle cell anaemia (SCA). Limited access to magnetic resonance imaging and angiography (MRI-MRA) in sub-Saharan Africa impedes detection of clinically unapparent cerebrovascular injury. Blood-based brain biomarkers of cerebral infarcts have been identified in non-SCA adults. Using plasma samples from a well-characterized cross-sectional sample of Ugandan children with SCA, we explored relationships between biomarker levels and MRI-detected cerebral infarcts and transcranial Doppler (TCD) arterial velocity. Testing was performed using a 4-plex panel of brain injury biomarkers, including neurofilament light chain (NfL), a central nervous system neuron-specific protein. Mean biomarker levels from the SCA group (n = 81) were similar to those from non-SCA sibling controls (n = 54). Within the SCA group, NfL levels were significantly higher in those with MRI-detected infarcts compared to no infarcts, and higher with elevated TCD velocity versus normal velocity. Elevated NfL remained strongly associated with MRI-detected infarcts after adjusting for sex and age. All non-SCA controls and SCA participants lacking MRI-detected infarcts had low NfL levels. These data suggest potential utility of plasma-based NfL levels to identify children with SCA cerebrovascular injury. Replication and prospective studies are needed to confirm these novel findings and the clinical utility of NfL versus MRI imaging.

Enhanced IgG immune response to COVID-19 vaccination in patients with sickle cell disease.

Patients with sickle cell disease (SCD) are considered to be immunocompromised, yet data on the antibody response to SARS-CoV-2 vaccination in SCD is limited. We investigated anti-SARS-CoV-2 IgG titres and overall neutralizing activity in 201 adults with SCD and demographically matched non-SCD controls. Unexpectedly, patients with SCD generate a more robust and durable COVID-19 vaccine IgG response compared to matched controls, though the neutralizing activity remained similar across both cohorts. These findings suggest that patients with SCD achieve a similar antibody response following COVID-19 vaccination compared to the general population, with implications for optimal vaccination strategies for patients with SCD.

Vaccination in sickle cell disease: Immunocompromised or immunocompetent?

Sickle cell disease (SCD) is an immunocompromised condition and patients with SCD may have a reduced immune response to certain vaccinations. The report by Nakahara et al. demonstrated that SCD patients exhibited elevated and more sustained IgG production following COVID-19 vaccination, when compared to healthy controls. This suggests that the immune response to vaccinations may vary among different types of vaccines in individuals with SCD. Commentary on: Nakahara et al. Enhanced IgG immune response to COVID-19 vaccination in patients with sickle cell disease. Br J Haematol 2023;202:937-941.

Significant haemoglobinopathies: A guideline for screening and diagnosis: A British Society for Haematology Guideline: A British Society for Haematology Guideline.

Antenatal screening/testing of pregnant women should be carried out according to the guidelines of the National Health Service (NHS) Sickle Cell and Thalassaemia Screening Programme. Newborn screening and, when necessary, follow-up testing and referral, should be carried out according to the guidelines of the NHS Sickle Cell and Thalassaemia Screening Programme. All babies under 1 year of age arriving in the United Kingdom should be offered screening for sickle cell disease (SCD). Preoperative screening for SCD should be carried out in patients from ethnic groups in which there is a significant prevalence of the condition. Emergency screening with a sickle solubility test must always be followed by definitive analysis. Laboratories performing antenatal screening should utilise methods that are capable of detecting significant variants and are capable of quantitating haemoglobins A2 and F at the cut-off points required by the national antenatal screening programme. The laboratory must ensure a provisional report is available for antenatal patients within three working days from sample receipt.

Brain volume in Tanzanian children with sickle cell anaemia: A neuroimaging study.

Brain injury is a common complication of sickle cell anaemia (SCA). White matter (WM) and cortical and subcortical grey matter (GM), structures may have reduced volume in patients with SCA. This study focuses on whether silent cerebral infarction (SCI), vasculopathy or anaemia affects WM and regional GM volumes in children living in Africa. Children with SCA (n = 144; aged 5-20 years; 74 male) and sibling controls (n = 53; aged 5-17 years; 29 male) underwent magnetic resonance imaging. Effects of SCI (n = 37), vasculopathy (n = 15), and haemoglobin were assessed. Compared with controls, after adjusting for age, sex and intracranial volume, patients with SCA had smaller volumes for WM and cortical, subcortical and total GM, as well as bilateral cerebellar cortex, globus pallidus, amygdala and right thalamus. Left globus pallidus volume was further reduced in patients with vasculopathy. Putamen and hippocampus volumes were larger in patients with SCA without SCI or vasculopathy than in controls. Significant positive effects of haemoglobin on regional GM volumes were confined to the controls. Patients with SCA generally have reduced GM volumes compared with controls, although some subcortical regions may be spared. SCI and vasculopathy may affect the trajectory of change in subcortical GM and WM volume. Brain volume in non-SCA children may be vulnerable to contemporaneous anaemia.

Early splenomegaly and septicaemia in homozygous sickle cell disease: A birth cohort study.

BACKGROUND: Patients with homozygous sickle cell disease (HbSS) and clinical splenomegaly by 6 months of age appeared at greater risk of invasive infections after 5 years of the Jamaican Cohort Study. We determined whether this risk remained significant over a longer study period, using a more rigorous definition of infection and examining the contribution of potential confounders. METHODS: Newborn screening of 100,000 consecutive deliveries during 1973-1981 detected 311 births with HbSS. Age at first clinical splenomegaly was used to categorize 285 of these patients in whom this could be determined: at or before 7 months (early), after 7 months (later), or 'never' palpated despite repeated examinations. Infective episodes were confined to 'first infections confirmed by positive culture'. Using a generalized linear model, the risk of septicaemia was assessed in each group, after adjusting for potential confounders. RESULTS: Of 93 'first infections', 42 occurred in 105 subjects in the 'early' group, 49 in 157 subjects in the 'later' group, and two in 23 subjects in the 'never' group; the observed to expected ratio of 1.42, 0.90 and 0.22 was highly significant (p = .003). Assessed as risk ratios, 'early' splenomegaly had a significantly higher risk ratio (RR) for septicaemia (RR = 7.4, confidence interval [CI]: 1.1-50.7, p < .05) when compared to the 'never' group adjusting for vaccine exposure and foetal haemoglobin concentration. The most common organisms were Streptococcus pneumoniae, Salmonella species, Haemophilus influenzae and Staphylococcus aureus. CONCLUSION: Early clinical splenomegaly in HbSS remains a predictor of septicaemia, defining a group that may require closer monitoring.

Cystatin C-derived estimated glomerular filtration rate in children with sickle cell anaemia.

BACKGROUND: Sickle cell disease is the most common inherited blood disorder in humans and constitutes a major public health burden. It is a multisystemic condition with long-term renal complications. Early detection of sickle cell nephropathy and initiation of appropriate interventions are associated with improved survival and quality of life. This study aimed to compare the cystatin C-derived estimated glomerular filtration rate (GFR) of the study groups and also, to correlate the clinical features of chronic kidney disease (CKD) with decreased GFR in children with sickle cell anaemia (SCA). METHODS: This hospital-based cross-sectional analytic study recruited 86 SCA subjects in steady-state and 86 age and sex-matched healthy HbAA controls aged 1-14 years who attended the Paediatric Haematology and Outpatient clinics of Federal Medical Centre Bida over six months. Data were collected using a semi-structured questionnaire, and participants' length/height, weight, and blood pressure were measured using standard procedures. Blood samples were drawn for serum cystatin C assay via the sandwich enzyme-linked immunosorbent assay (ELISA) technique. Filler's equation was used to calculate the glomerular filtration rate. RESULTS: There was a significant difference in the mean cystatin C-derived GFR between the two groups, i.e. 116 ± 30mL/min/1.73m2 vs. 106 ± 24mL/min/1.73m2 for the SCA and control groups, respectively (p = 0.017). The prevalence of supernormal GFR (i.e. GFR > 140mL/min/1.73m2) and decreased GFR (i.e. GFR < 90mL/min/1.73m2) was 19.8% and 22.1%, respectively, in children with SCA. There was no significant association between the age at diagnosis of SCA, blood transfusions, blood pressure, packed cell volume and presence of peripheral oedema with decreased GFR in the study subjects. CONCLUSIONS: Supernormal GFR is common in children with SCA and there is no significant association between clinical features of CKD with decreased GFR. Regular evaluation of renal function is, however, recommended in children with SCA for early detection and treatment of renal complications in order to halt the progression to end-stage kidney disease (ESKD).

Evaluation of Homocysteine Status and its Correlation with Disease Severity in Individuals with Sickle Cell Anaemia in Steady State.

INTRODUCTION: Sickle cell anaemia (SCA) is a genetic disorder associated with chronic inflammation and a hypercoagulable state. This study evaluated the serum homocysteine level and its correlation with disease severity and body mass index (BMI) among individuals with SCA in a steady state. METHODS: A cross-sectional study was carried out and the serum level of homocysteine was analysed using the ELISA method. Disease severity and BMI were also calculated. Data generated were analyzed using SPSS software, version 21. RESULTS: Ninety subjects participated in this study and were made up of 30 homozygous sickle cell (HbSS, SCA) subjects, 30 individuals with sickle cell trait (HbAS), and 30 individuals with normal adult haemoglobin (HbAA) with a mean age of 27.3 ± 6.4years, 26.0 ± 6.0years, and 27.2 ± 6.6years respectively. The mean serum level of homocysteine among HbSS was 26.2 ± 11.8umol/l which was significantly higher than 17.9 ± 8.0umol/l and 18.9 ± 7.9umol/l among HbAA or HbAS respectively (p< 0.05). Mean BMI of 21.9 ± 2.8kg/m2 among HbSS was significantly lower than those of HbAS (23.7 ± 2.5kg/m2) and HbAA (24.7 ± 2.4kg/m2) (p<0.05). There was a positive correlation between homocysteine level and disease severity in patients with HbSS, though not significant (r = 0.168; p>0.05). There was a significant negative correlation between homocysteine level and BMI(r = -0.0258; p = 0.021); and between disease severity and BMI (r = -0.400; p = 0.028). CONCLUSION: Individuals with HbSS have significantly higher mean serum homocysteine level and lower BMI compared to HbAS and HbAA. There was a positive correlation between homocysteine level and disease severity, though not significant but a strong negative correlation between homocysteine levels and BMI, and between disease severity and BMI among HbSS participants. A similar study should be carried out on a wide scale to determine the actual relationship between homocysteine level and disease severity in SCA and whether patients will benefit from routine administration of vitamin B12, vitamin B6, and folic acid.

INTRODUCTION: La drépanocytose est une maladie génétique associée à une inflammation chronique et à un état d'hypercoagulabilité. Cette étude a évalué le taux d'homocystéine sérique et sa corrélation avec la gravité de la maladie et l'indice de masse corporelle (IMC) chez les personnes atteintes d'anémie drépanocytaire à l'état stable. MÉTHODES: Une étude transversale a été réalisée et le taux sérique d'homocystéine a été analysé à l'aide de la méthode ELISA. La gravité de la maladie et l'IMC ont également été calculés. Les données générées ont été analysées à l'aide du logiciel SPSS, version 21. RÉSULTATS: Quatre-vingt-dix sujets ont participé à cette étude, dont 30 drépanocytaires homozygotes (HbSS, SCA), 30 drépanocytaires de trait (HbAS) et 30 personnes ayant une hémoglobine adulte normale (HbAA), âgés en moyenne de 27,3 ±6,4 ans, 26,0 ±6,0 ans et 27,2 ±6,6 ans, respectivement. Le taux sérique moyen d'homocystéine chez les HbSS était de 26,2 ±11,8 umol/l, ce qui était significativement plus élevé que 17,9 ±8,0umol/l et 18,9 ±7,9umol/l chez les HbAA ou HbAS respectivement (p< 0,05). L'IMC moyen de 21,9 ±2,8kg/m2 chez les HbSS était significativement inférieur à celui des HbAS (23,7±2,5kg/m2) et des HbAA (24,7 ±2,4kg/ m2) (p<0,05). Il y avait une corrélation positive entre le niveau d'homocystéine et la sévérité de la maladie chez les patients HbSS, bien que non significative (r= 0.168 ; p>0.05). Il existe une corrélation négative significative entre le taux d'homocystéine et l'IMC (r= - 0,0258 ; p = 0,021) ; et entre la gravité de la maladie et l'IMC (r = - 0,400 ; p = 0,028). CONCLUSION: Les personnes atteintes de HbSS ont un taux moyen d'homocystéine sérique significativement plus élevé et un IMC plus faible que les personnes atteintes de HbAS et de HbAA. Il existe une corrélation positive entre le taux d'homocystéine et la gravité de la maladie, une corrélation négative non significative mais forte entre le taux d'homocystéine et l'IMC, et entre la gravité de la maladie et l'IMC chez les participants HbSS. Une étude similaire devrait être menée à grande échelle pour déterminer la relation réelle entre le taux d'homocystéine et la gravité de la maladie dans le SCA et pour savoir si les patients bénéficieront de l'administration systématique de vitamine B12, de vitamine B6 et d'acide folique. Mots clés: Gravité de la maladie, homocystéine, anémie drépanocytaire.