High risk APOL1 genotypes and kidney disease among treatment naïve HIV patients at Kano, Nigeria.

INTRODUCTION: Racial disparities are known in the occurrence of kidney disease with excess risks found among people of African descent. Apolipoprotein L1 (APOL1) gene variants G1 and G2 are associated with kidney disease among HIV infected individuals of African descent in the USA as well as among black population in South Africa. We set out to investigate the prevalence of these high-risk variants and their effects on kidney disease among HIV infected patients in Northern Nigeria with hitherto limited information despite earlier reports of high population frequencies of these alleles from the Southern part of the country. METHODS: DNA samples obtained from the whole blood of 142 participants were genotyped for APOL1 G1 and G2 variants after initial baseline investigations including assessment of kidney function. Participants comprised 50 HIV positive patients with no evidence of kidney disease, 52 HIV negative individuals with no kidney disease and 40 HIV positive patients with chronic kidney disease (CKD) evidenced by persistent proteinuria and/or reduced eGFR, who also had a kidney biopsy. All the HIV positive patients were newly diagnosed and treatment naïve. RESULTS: The distribution of the APOL1 genotypes among the study participants revealed that 24.6% had a G1 risk allele and 19.0% a G2. The frequency of the High Risk Genotype (HRG) was 12.5% among those with CKD compared to 5.8% in the HIV negative group and zero in the HIV positive no CKD group. Having the HRG was associated with a higher odds for developing HIV Associated Nephropathy (HIVAN) (2 vs 0 risk alleles: OR 10.83, 95% CI 1.38-84.52; P = 0.023; 2 vs 0 or 1 risk alleles: OR 5.5, 95% CI 0.83-36.29; P = 0.07). The HRG was also associated with higher odds for Focal Segmental Glomerulosclerosis (FSGS) (2 vs 0 risk alleles: OR 13.0, 95% CI 2.06-81.91; P = 0.006 and 2 vs 0 or 1 risk alleles: OR 9.0, 95%CI 1.62-50.12; P = 0.01) when compared to the control group. CONCLUSION: This study showed a high population frequency of the individual risk alleles of the APOL1 gene with higher frequencies noted among HIV positive patients with kidney disease. There is high association with the presence of kidney disease and especially FSGS and HIVAN among treatment naive HIV patients carrying two copies of the HRG.

Histopathological Pattern of Kidney Diseases Among HIV-Infected Treatment-Naïve Patients in Kano, Nigeria.

INTRODUCTION: Kidney biopsy in patients with HIV-associated kidney diseases allows for histopathologic diagnosis and institution of appropriate treatment as well as proper prognostication. There is a paucity of data on the histopathological pattern of HIV-associated kidney diseases in most sub-Saharan African countries. This study was aimed at evaluating the histopathologic patterns of kidney diseases seen among HIV-infected treatment-naive patients in our center as this will allow for proper diagnosis and institution of appropriate treatment. METHODS: In this cross-sectional study, consecutive patients who satisfied inclusion criteria and consented to participate were recruited. Percutaneous kidney biopsies were carried out as day procedures under real-time ultrasound guidance using an automatic spring-loaded biopsy gun as per our unit protocols. Baseline investigations including urea, creatinine, electrolytes, CD4 count, complete blood count, and glomerular filtration rate (eGFR) calculations, urinalysis and urine protein creatinine ratios were done on all the participants. RESULTS: Fifty-five patients who satisfied the inclusion criteria were studied. The mean age of the study population was 38.34± 9.26 years, with 32% females. Mean serum creatinine was 249.6±164.6 µmol/L, and mean CD4 count was 238 ±210 cells/mL. The commonest histological type was FSGS seen in 20 patients (37.7%), followed by HIVAN seen in 17 (32.1%) patients; chronic interstitial nephritis in 7 patients (13.2%) and 6 (11%) had no significant pathological finding. Compared to non-HIVAN, HIVAN patients tended to have higher systolic BP (p= 0.05); higher serum creatinine levels (p= 0.05); lower eGFR (0.03) and higher urine protein to creatinine ratio [uPCR; p= 0.02]. CONCLUSION: Kidney involvement is still a form of presentation among HIV-infected treatment-naïve patients and though a wide range of glomerular and tubulointerstitial lesions may be seen, FSGS and HIVAN are still the most common. We recommend assessment of kidney function, including urinalysis, as part of the routine evaluation of newly diagnosed HIV patients and biopsy where indicated to prognosticate and institute appropriate early treatment.