Objective: To determine the prevalence and predictors of microalbuminuria (MA) (urine albumin-creatinine ratios (ACRs) of 30-300 µg/mg) in children with homozygous sickle cell (Hb SS) disease in Jamaica.
Patients and methods: 244 children with Hb SS disease were screened for MA. Blood samples and a retrospective review of patient records were used to determine haematological, biochemical and clinical correlates for MA.
Results: The prevalence of MA was 18.4%. The youngest child with MA was 2.8 years old. The distribution of urine ACRs was right skewed and normalised by natural log transformation. Abnormal urine ACRs ranged from 32 to 260 µg/mg. In univariable analyses with log ACR as outcome, ever having dactylitis (β=0.44; 95% CI 0.08 to 0.80; p<0.02), glomerular hyperfiltration (β=0.6; 95% CI 0.26 to 0.94; p<0.001), age (β=0.07; 95% CI 0.01 to 0.12; p<0.02), estimated glomerular filtration rate (eGFR) (β=0.01; 95% CI 0.005 to 0.02; p<0.001), haemoglobin concentration (β=-0.18; 95% CI -0.34 to -0.02; p<0.03) and haemoglobin F (β=-0.03; 95% CI -0.05 to -0.003; p<0.04) were significantly associated with MA but lactate dehydrogenase (a marker of haemolysis) was not. Adjusting for gender, age (β=0.08; 95% CI 0.02 to 0.15; p=0.01), eGFR (β=0.01; 95% CI 0.001 to 0.01; p=0.03) and body mass index (β=-0.16; 95% CI -0.28 to -0.03; p=0.02) were predictors of MA.
Conclusions: MA is seen as early as 2.8 years in children with sickle cell disease. Risk factors for MA include glomerular hyperfiltration, nutritional factors and vaso-occlusion but not haemolysis. Interventions addressing these factors may be useful.