Liver and renal biochemical profiles of people with sickle cell disease in Africa: a systematic review and meta-analysis of case-control studies

Abstract

Abstract
Background
Sickle cell disease (SCD) is a genetic blood disorder characterized by a painful vaso-occlusive crisis due to the sickling of red blood cells in capillaries. Complications often lead to liver and renal dysfunctions, contributing to morbidity and mortality, particularly for children under 5. This systematic review and meta-analysis aimed to evaluate the liver and renal functions of people with SCD (HbSS) compared to those without it (HbAA) in Africa.

Methods
The protocol was registered with PROSPERO (CRD42022346771). We searched PubMed, Embase, Web of Science, and Google Scholar using the keywords “liver function”, “renal function”, “sickle cell disease”, and “Africa” on 6th May 2023 for peer-reviewed articles with abstracts in English. We included case-control studies comparing SCD (HbSS) with controls without hemoglobinopathies (HbAA). We used the random-effect model to calculate the pooled average values for the blood tests of people with SCD in RStudio version 4.2.2.

Results
Overall, 17 articles were analyzed from five African countries involving 1312 people with SCD and 1558 controls. The pooled mean difference of liver enzymes aspartate transaminase (AST) was 8.62 (95% CI − 2.99–20.23, I2 = 97.0%, p < 0.01), alanine transaminase (ALT) 7.82 (95% CI − 0.16–15.80, I2 = 99%, p < 0.01) and alkaline phosphatase (ALP) − 2.54 (95% CI − 64.72 – 59.64, I2 = 99%, p < 0.01) compared to controls. The pooled mean difference for the renal biochemical profiles creatinine − 3.15 (95% CI − 15.02; 8.72, I2=99%, p < 0.01) with a funnel plot asymmetry of t = 1.09, df = 9, p = 0.3048 and sample estimates bias of 6.0409. The pooled mean difference for serum urea was − 0.57 (95% CI − 3.49; 2.36, I2 = 99%, p < 0.01), and the estimated glomerular filtration (eGFR) rate was 19.79 (95% CI 10.89–28.68 mL/min/1.73 m2, I2 = 87%, p < 0.01) compared to controls. Conclusion People with SCD have slightly elevated liver enzymes and estimated glomerular filtration rates compared to controls in Africa. With all the heterogeneity (I2) > 50%, there was substantial variation in the reported articles’ results.