Renal manifestations of human immunodeficiency virus in the era of antiretroviral treatment in South Africa.

Abstract

Background: Sub-Saharan Africa carries the global burden of human immunodeficiency virus (HIV) infection. Renal disease is a well-recognized and closely associated complication of HIV infection. The burden of kidney disease in Africa is aggravated by poor socio-economic factors and by the lack of access to healthcare and to resources. Most of what is known regarding HIV related kidney disease has come from research done in high income countries. Aim: Demonstrating the current stance on renal manifestations of HIV in South Africa in the era of antiretroviral treatment (ART). Study design: This is a cross-sectional study. Mixed data acquisition methods using qualitative and quantitative research approaches were applied in this study in order to achieve the objectives. These included a systematic scoping review and a retrospective chart review. Data collection and analysis: The systematic scoping review began with a database search of published literature based on studies conducted in South Africa. The following databases: Google Scholar, PubMed, Medline, Cochrane Library, Worldcat.org and EBSCO host were searched to obtain relevant literature. We formulated a standardized data extraction table according to the PICO model. We presented a narrative account of the findings by performing a thematic content analysis of the included studies. For the chart review we extracted data from medical records of all new patients initiated on ART from April 2010 to December 2013. The sample size was 350 patient records. We collected data at baseline (pre-ART) and then at 6, 12, 18 and 24 months on ART. Descriptive statistics were used to describe the characteristics of HIV-related renal manifestations at the King Edward VIII Hospital ART clinic. Results: The results of the systematic scoping review showed that normal renal function occurred in 28.4% to 79% of patients, mild renal impairment occurred in 19% to 57.1% and moderate renal impairment in 2% to 14.4%. Only 1.3% of patients had severe renal impairment. Both the Cockcroft-Gault equation (after correcting for bias) and the 4-variable Modification of Diet in Renal Disease equation (without the ethnicity factor for African Americans) have been validated for the estimation of glomerular filtration rate (eGFR) in Black South Africans. HIV-associated nephropathy was the most prevalent histology seen (57.2%). Older age, a lower CD4 count, a low haemoglobin and a detectable viral load were linked to renal impairment. Renal function improved in the first year of commencing ART. With regards to the chart review, 64% of the cohort was female, 99% were African and the mean age was 36.9±9.7 years. At baseline, 10 patients had hypertension, 6 had diabetes, 61 were co-infected with tuberculosis (TB) and 157 patients had a high body mass index (BMI) with 25.4% being categorized as overweight and 19.4% obese. Regarding baseline renal function, the majority of the patients had a normal renal function: 90.4% (95% confidence intervals (CI):86%-93%); 7.0% (CI:5%-10%) had moderate renal impairment; 1.3% (CI:0%-3%) had severe renal impairment; and 1.3% (CI:0%-3%) had kidney failure. The risk of renal impairment increased by 1.06 (CI: 1.03 – 1.10) times as BMI increased by one unit. The association of hypertension (HPT) with abnormal renal function was found to be insignificant, p>0.05. The majority of patients were initiated on tenofovir disoproxil fumarate (TDF) (90.6%), in combination with lamivudine (3TC) (100%) and either efavirenz (EFV) (56.6%) or nevirapine (NVP) (43.4%). Conclusion: The scoping review highlights age, CD4 cell count, haemoglobin, detectable viral load as factors associated with renal impairment and the improvement in renal function with use of ART. As more patients are started on ART according to the ‘test and treat’ approach to HIV prevention and management in South Africa, it is possible that the benefit may extend to the burden of kidney disease, however, hypertension, diabetes and obesity may reduce these benefits. The chart review found a low prevalence of baseline renal impairment in HIV-infected ART-naïve outpatients. An improvement in renal function after the commencement of ART has been demonstrated among this population. However, the long-term outcomes of patients with HIV-related renal disease is not known.