Vitamin D, bilirubin and urinary albumin-creatinine ratio in adults with sickle cell anaemia

Abstract

The interaction between vitamin D deficiency (VDD) and dysfunction of both the kidney and liver is still poorly understood in different health states of SCA. This study determined serum levels of vitamin D and indices of liver and renal function in adult sickle cell anaemia subjects. Sixty subjects with sickle cell anaemia (30 in steady state [SSCA] and 30 in vaso-occlusive crisis [VOC]) and 30 apparently healthy individuals with HbAA genotype were recruited into this study. Standard methods were used for the determination of total protein, albumin, bilirubin, urinary creatinine and albumin while serum vitamin D was determined using ELISA. Differences between groups were determined using Student’s t-test or Man-Whitney U test as appropriate with p<0.05 considered as statistically significant. Serum vitamin D was significantly lower in sickle cell anemia (SCA) subjects and the deficiency was more profound in VOC when compared with the control subjects. SCA subjects with vitamin D level <50 nmol/L had significantly higher levels of total bilirubin (TBIL) and conjugated bilirubin (CBIL) compared with those who had ≥50 nmol/L vitamin D level. There was no significant difference in vitamin D level between SCA subjects with one or less episode of SCA crisis per year and SCA subjects with two or more episodes of SCA crisis per year although, the median vitamin D level was lower in the latter. Vitamin D deficiency is more pronounced in SCA subjects in vaso-occlusive crisis and elevated serum bilirubin was observed in SCA subjects with low serum vitamin D level.