Disease severity and renal function among sickle cell anaemia patients in a tertiary hospital, South-south, Nigeria: a cross sectional study.

Background: Renal disease is a recognized complication of sickle cell anaemia (SCA), especially from the third decade of life and is linked to disease severity. This study assessed the association between disease severity and renal function among SCA patients using routine and newer markers of renal function. Methods: This cross-sectional study recruited 85 SCA patients. Disease severity was assessed using modified Adegoke criteria which include the frequency of transfusion, painful crises, packed cell volume, and history of complications such as hypertension and chronic leg ulcers. Renal function was assessed using urea, creatinine, and beta-2-microglobulin (β2-M). Association was determined between renal function and disease severity using Pearson's correlation. P-value < 0.05 was taken as significant. Results: The mean age of participants was 27.2 ± 7.6 years with 41(48.2%) males and 44 (51.8%) females. The mean packed cell volume, serum creatinine, serum urea, and β2-M were 24.0± 4.1%,17.6±7.5 mg/dL, 0.7±0.3mg/dL, 3.4±1.2mg/l respectively. A majority (54.1%) of them had a mild disease while 35.3% and 10.6% had moderate and severe diseases, respectively. Forty of the SCA patients had urine specific gravity below 1.010. The mean values of systolic blood pressure (p=0.001) diastolic blood pressure (p=0.001), serum creatinine (p=0.028) and β2M (p=0.019) significantly increased with disease severity. There was a significant positive correlation between SCA disease severity and serum urea (r=0.229; p=0.035), and serum β2-microglobulin (r=0.270; p=0.012). Conclusion: Sickle cell anaemia severity is associated with a decline in renal function using both traditional and novel renal markers. Serum β2-M may serve as a useful marker of renal function and disease severity in SCA.