High body mass index in children with sickle cell disease: a retrospective single-centre audit.
ABSTRACT: Objective:To assess the prevalence of high body mass index (BMI) in children with sickle cell disease and assess correlation between BMI and disease severity. Design:Retrospective chart review followed by statistical analysis. Setting:A single tertiary paediatric clinic in inner city London. Patients:All patients with sickle cell disease, including homozygous haemoglobin (HbSS) and compound heterozygous Hb (HbSC), age 2-18 years receiving clinical care at the centre, were included in the study. Interventions:Height and weight measurements, steady-state laboratory blood tests, hospital admission rates, adjunct therapy such as hydroxycarbamide or blood transfusions and obstructive sleep apnoea (OSA) data were obtained from the hospital electronic patient records. Main outcome measures:To study the prevalence of high BMI and to identify any correlation between BMI and disease severity. Results:385 patients were included. 64 children (17%) were overweight or obese, of which a significantly higher number of children with HbSC were obese or overweight (23 out of 91, 25%) compared with those with HbSS (36 out of 273, 13%), p?0.001. No correlation was found between high BMI and presence of OSA, and markers of disease severity such as admission rates, fetal haemoglobin or lactate dehydrogenase levels. Conclusions:High BMI did not correlate with disease severity in this cohort of patients with sickle cell disease. Obesity was more prevalent in females and those with HbSC. Further prospective studies are needed to determine long-term effects of BMI in disease severity and outcome.
Project description: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.
Project description:Sickle cell disease (SCD) in patients of HbSC genotype is considered similar, albeit milder, to that in homozygous HbSS individuals--but with little justification. In SCD, elevated red cell cation permeability is critical as increased solute loss causes dehydration and encourages sickling. Recently, we showed that the KCl cotransporter (KCC) activity in red cells from HbSC patients correlated significantly with disease severity, but that in HbSS patients did not. Two transporters involved in red cell dehydration, the conductive channels Psickle and the Gardos channel, behaved similarly in red cells from the two genotypes, but were significantly less active in HbSC patients. By contrast, KCC activity was quantitatively greater in HbSC red cells. Results suggest that KCC is likely to have greater involvement in red cell dehydration in HbSC patients, which could explain its association with disease severity in this genotype. This work supports the hypothesis that SCD in HbSC patients is a distinct disease entity to that in HbSS patients. Results suggest the possibility of designing specific treatments of particular benefit to HbSC patients and a rationale for the development of prognostic markers, to inform early treatment of children likely to develop more severe complications of the disease.
Project description:Sickle cell disease (SCD) is an inherited anemia that afflicts millions worldwide. Kidney disease is a major contributor to its morbidity and mortality. We examined contemporary and historical SCD populations to understand how renal disease behaved in hemoglobin SS (HbSS) compared with HbSC.Kidney function was examined in the multicentered Treatment of Pulmonary Hypertension and Sickle Cell Disease with Sildenafil Therapy (Walk-PHaSST) Trial (HbSS=463; HbSC=127; years 2007-2009) and historical comparator populations from the Cooperative Study of Sickle Cell Disease (CSSCD; HbSS=708) and the Multicenter Study of Hydroxyurea in Sickle Cell Disease (MSH; HbSS=299).In adults with SCD, eGFR was lower among older individuals: -1.78 ml/min per 1.73 m(2) per year of age (95% confidence interval [95% CI], -2.06 to -1.50; Walk-PHaSST Trial), -1.75 ml/min per 1.73 m(2) per year of age (95% CI, -2.05 to -1.44; MSH), and -1.69 ml/min per 1.73 m(2) per year of age (95% CI, -2.00 to -1.38; CSSCD) in HbSS compared with -1.09 ml/min per 1.73 m(2) per year of age (95% CI, -1.39 to -0.75) in HbSC (Walk-PHaSST Trial). Macroalbuminuria was seen in 20% of participants with SCD (HbSS or HbSC; P=0.45; Walk-PHaSST Trial), but microalbuminuria was more prevalent in HbSS (44% versus 23% in HbSC; P<0.002). In the Walk-PHaSST Trial, albuminuria was associated with hemolysis (higher lactate dehydrogenase, P<0.001; higher absolute reticulocyte count, P<0.02; and lower Hb, P=0.07) and elevated systolic BP (P<0.001) in HbSS. One half of all participants with HbSS (20 of 39) versus one fifth without (41 of 228) elevated tricuspid regurgitant jet velocity (?3 m/s; adverse prognostic indicator in SCD) had macroalbuminuria (P<0.001). In the CSSCD, overt proteinuria, detected (less sensitively) by urine dipstick, associated with higher 3-year mortality (odds ratio, 2.48; 95% CI, 1.07 to 5.77). Serum bicarbonate was lower in HbSS (23.8 versus 24.8 mEq/dl in HbSC; P<0.05) and associated with reticulocytopenic anemia and decreased renal function.In SCD, albuminuria or proteinuria was highly prevalent, in HbSS more than in HbSC. Proteinuria associated with mortality in HbSS. Older individuals had a lower than expected eGFR, and this was more prominent in HbSS. Current management does not routinely address renal complications in SCD, which could plausibly reduce morbidity and mortality.
Project description:To study degrees of chronic kidney disease (CKD) using creatinine clearance in adult Nigerian patients with sickle-cell disease (SCD).One hundred SCD patients, made up of 79 HbSS (homozygous haemoglobin S) patients and 21 HbSC (heterozygous haemoglobins S and C) patients, were investigated prospectively, along with 50 normal controls. Their sociodemographic data, weight and drug history were documented. Each participant underwent dipstick urinalysis, and creatinine clearance was calculated following a 24-hour urine collection and serum creatinine measurement. They were categorized into stages of CKD based on the creatinine clearance.Of the 79 HbSS patients, 14 (18%), 28 (35%), 33 (42%) and 4 (5%) had stage 1, 2, 3 and 4 CKD, respectively. In the HbSC group, 3 (14%), 9 (43%) and 9 (43%) patients had stage 1, 2 and 3 CKD, respectively. Proteinuria was noted in 16 (20%) HbSS patients but not in any of the HbSC patients. Of the subjects aged ?24 years (n = 49), 9 (18%), 18 (37%), 21 (43%) and 1 (2%) had stage 1, 2, 3 and 4 CKD, respectively. Of those aged >24 years (n = 51), 8 (16%), 19 (37%), 21 (41%) and 3 (6%) had stage 1, 2, 3 and 4 CKD, respectively. None of the subjects had stage 5 CKD.In this study, the adult subjects with SCD had various degrees of CKD. Adequate follow-up and active intervention are advocated to delay the onset of end-stage nephropathy.
Project description:Sickle cell disease (SCD) is caused by a pathogenic hemoglobin (Hb) mutation, yet patients can have dramatically variable clinical manifestations. Here we address the genetic basis of this clinical heterogeneity. Using a systems genetics approach, we performed whole blood gene expression analysis and eQTL analysis on different clinical phenotypes in SCD patients. We generated whole blood gene expression profiles for 311 West-African children recruited from the National Sickle Cell Disease Centre in Cotonou, Benin which included 250 patients with varying degrees of SCD severities and 61 age-matched controls. SCD is caused by a point-mutation in the beta-hemoglobin gene that changes the normal HbAA protein into, most often, an abnormal HbSS or HbSC protein. The SCD patients recruited in the study either had HbSS or HbSC phenotypes and were categorized into different 3 clinical states based on follow-up status (Rahimy, MC, et al. Effect of a comprehensive clinical care program on disease course in severely ill children with sickle cell anemia in sub-Saharan African setting. Bood 102, 834-838. 2002). When patients are refered to the clinic, they are enrolled when they are in steady-state condition, and are labeled as entry (E). Patients followed at the SCD clinic are labeled as FU. Control patients were recruited and are labeled as C. Patients were also assigned a severity score (Sebastiani, P. et al. A network model to predict the risk of death in sickle cell disease. Blood 110, 2727-2735, 2007). Hemoglobin protein status (Hb phenotype) was confirmed for each patient using standard electrophoretic techniques. We generated genotypes for 263 of these individuals and performed principal component analysis (PCA) which identified 2 signigicant genotypic principal components (gPC1 and gPC2). Using the gene expression and genotyping data, we performed an eSNP analysis. . Gene expression data presented in this study.
Project description:Acute splenic sequestration crisis (ASSC) is a hematological emergency in young children with sickle cell disease (SCD), characterized by worsening anemia and splenomegaly, usually with reticulocytosis and thrombocytopenia. Transient aplastic crisis (TAC) due to parvovirus B19 infection occurs in older children with SCD, and typically manifests as worsening anemia with reticulocytopenia and no splenomegaly. Five older children with SCD (4 HbSC, 1 HbSS on hydroxyurea) developed ASSC concurrent with TAC and had a severe clinical course. Our cases suggest that older children with SCD and acute parvovirus infection should be monitored closely for splenomegaly and multi-system dysfunction.
Project description:BACKGROUND:Red blood cell (RBC) polymorphisms are suggested to influence the course of Plasmodium falciparum malaria. Whereas some variants have been found to be protective, others have been found to enhance parasite development. This study evaluated the effect of variant haemoglobin (Hb) and ABO blood groups on P. falciparum merozoite invasion, multiplication rates as well as gametocyte development. METHODS:Approximately 2.5 mL of venous blood was collected from each participant. Flow cytometry was used to determine the in vitro merozoite invasion rates of NF54 parasites into the blood of 66 non-parasitaemic individuals with variant Hb genotypes (HbSS, HbSC) and blood groups (A, B, O), which were then compared with invasion into HbAA blood. The ex vivo asexual parasite multiplication and gametocyte production rates of parasites from 79 uncomplicated malaria patients with varying Hb genotypes (HbAS, HbAC and HbAA) were also estimated using microscopy. RESULTS:Merozoite invasion rates were significantly reduced by about 50% in RBCs containing HbSS and HbSC relative to HbAA cells. The presence of blood group O and B reduced the invasion rates of HbSS by about 50% and 60%, respectively, relative to HbSC but the presence of blood group A removed the inhibitory effect of HbSS. The initial parasite densities in uncomplicated malaria patients with Hb genotypes HbAS and HbAC cells were similar but significantly lower than those with genotype HbAA. The ex vivo parasite multiplication rate, gametocytaemia and gametocyte conversion rates followed a similar trend but did not reach statistical significance (p?>?0.05). CONCLUSIONS:Parasite invasion rate into erythrocytes is dependent on both erythrocyte blood group antigen and haemoglobin genotype as blood group O and B provided protection via reduced merozoite invasion in RBCs containing HbSS relative to HbSC. Regardless of haemoglobin type, greater than 70% malaria patients had circulating ring stage parasites that differentiated into stage II gametocytes in 4 days.
Project description:Background:It is estimated that one out of every three Ghanaians has hemoglobin genotype mutation. This change in genetic make-up may result in genotypes such as HbAS, HbSS, and HbSC. Many children in low- and middle-income countries die even before they are diagnosed with sickle cell disease (SCD). In Africa, there are limited data on the incidence and prevalence of SCD and the Volta region of Ghana is no exception. Aim:The aim of this study was to determine the prevalence of SCD and to assess the hemoglobin variants among patients attending Ho Teaching Hospital. Methods:A retrospective study design was used to extract information from the Hospital Administration and Management Systems (HAMS) on the hemoglobin electrophoresis results and corresponding full blood count results of the SCD and sickle cell anemia (SCA) patients as well as patients who were asked to do Hb electrophoresis irrespective of their sickling status. Data were collected for the period January 2016 to December 2018. Sickle cell disease status was determined using the Hb genotypes from the Hb electrophoresis results. The full blood count was used to categorize the severity of anemia based on the hemoglobin concentration in the SCA and SCD patients. Results:A total of 1,523 subjects were included in the study of which the prevalence for sickle cell disease was 16.7%. The SCD genotypes included HbS (6.2%), HbSC (7.9%), and HbSF (2.6%). Hemoglobin C disease (HbCC) constituted 0.3% out of the total prevalence of SCD. The prevalence of anemia was 99.2%, with the severest form in HbS. Also, majority of the SCD patients had severe anemia. Difference in the severity of anemia was found to be significant among both male (P=0.006) and female (P=0.004) participants with SCD. Conclusion:Patients receiving health care at the Ho Teaching Hospital had different hemoglobin variants with HbAS recording the highest prevalence. The high incidence of hemoglobin AS implies the possibility of having an increased population of individuals with sickle cell disease in future if measures are not put in place to improve screening, counseling, and education of the public about the health threat SCD poses.
Project description:BACKGROUND:Alterations in the structure of haemoglobin (Hb) are usually brought about by point mutations affecting one or, in some cases, two codons encoding amino acids of the globin chains. One in three Ghanaians are said to have sickle cell disorders, whereas malaria continues to be one of the leading causes of mortality among children. This study determined the prevalence of sickle cell disorders and malaria infection among children aged 1-12 years in the Volta Region. METHODS:This was a community-based cross-sectional survey that involved 938 children aged 1-12 years selected from three districts, one each from the 3 geographical zones of the Volta Region using a multistage sampling method. Demographic information was collected using a standard questionnaire and anthropometric indices were measured. Isoelectric focusing (IEF) electrophoresis was used to determine the Hb genotypes and sub-microscopic parasites were determined by PCR. RESULTS:The prevalence of sickling screening positive was 16.0% with an overall prevalence of sickle cell disorders being 2.0%. Among the individual genotypes making up the sickle cell disorders, genotype HbSF was the highest (0.9% as compared to 0.2%; HbSS, 0.6%; HbSC and 0.3%; HbSCF). Microscopic Plasmodium falciparum parasitaemia was detected among 5.5% of the children and 14.2% sub-microscopic prevalence by PCR. Children with sickle cell disorders were more likely to have sub-microscopic parasitaemia (AOR?=?5.51 95%CI (2.15, 14.10), p?<?0.001) as well as anaemia (AOR?=?3.03 95% CI (1.04, 8.82), p?=?0.042), compared to those with normal genotypes. There was no significant difference observed between sickle cell disorders and growth and development of the children screened. CONCLUSIONS:Sickle cell disorders were significantly associated with sub-microscopic parasitaemia as well as anaemia in this study. Establishment of sickle cell clinics in the district and regional hospitals will help in the management of children with the disorder and also generate a national database on sickle cell disorders. National neonatal screening policies must also be put in place to help in early detection and management of these disorders.
Project description:Fetal hemoglobin (HbF) is a strong modifier of sickle cell disease (SCD) severity and is associated with 3 common genetic loci. Quantifying the genetic effects of the 3 loci would specifically address the benefits of HbF increases in patients. Here, we have applied statistical methods using the most representative variants: rs1427407 and rs6545816 in BCL11A, rs66650371 (3-bp deletion) and rs9376090 in HMIP-2A, rs9494142 and rs9494145 in HMIP-2B, and rs7482144 (Xmn1-HBG2 in the ?-globin locus) to create g(HbF), a genetic quantitative variable for HbF in SCD. Only patients aged ?5 years with complete genotype and HbF data were studied. Five hundred eighty-one patients with hemoglobin SS (HbSS) or HbS?0 thalassemia formed the "discovery" cohort. Multiple linear regression modeling rationalized the 7 variants down to 4 markers (rs6545816, rs1427407, rs66650371, and rs7482144) each independently contributing HbF-boosting alleles, together accounting for 21.8% of HbF variability (r2) in the HbSS or HbS?0 patients. The model was replicated with consistent r2 in 2 different cohorts: 27.5% in HbSC patients (N = 186) and 23% in 994 Tanzanian HbSS patients. g(HbF), our 4-variant model, provides a robust approach to account for the genetic component of HbF in SCD and is of potential utility in sickle genetic and clinical studies.