Sero-prevalence, Genotypes and Risk Factors Associated with Hepatitis B Virus Infections among HIV Infected Patients Attending Malindi Sub-county Hospital in Kenya

Abstract

Human Immunodeficiency Virus (HIV) and Hepatitis B Virus (HBV) co-infections are common all over the world. Several studies have shown that HIV infection modifies the course of HBV infection by increasing rates of chronicity, prolonging the time the HBV stays in circulation and increasing liver-related morbidity. Factors such as intravenous drug use, multiple blood transfusions, presence of tattoos, unsafe sexual practices and being health workers have been implicated as drivers of infection & transmission of HBV & HIV. Determining the HBV genotypes and their diversity among HIV positive patients would help in their appropriate therapeutic management. This study was aimed at determining the sero-prevalence and genotypes of HBV isolated from HIV patients as well as the associated risk factors among patients attending the comprehensive care center at Malindi Sub-county Hospital in a descriptive cross-sectional study. Malindi was chosen as a suitable study site because of the high numbers of residents involved in sex tourism as well as intravenous drug use. A total of 446 HIV positive patients attending the CCC were recruited in this study upon consenting. Social demographic, clinical history and risk factors of the participants was obtained using a structured questionnaire. Five millilitres of whole blood was obtained from each participant, 50µl of which was used for CD4 cell counts using a flow cytometer. HBsAg serology was done using Hepanostika® HBsAg Ultra ELISA kit (BioMérieux SA) and HBV DNA was extracted from all HBsAg positive samples. Nested polymerise chain reaction (PCR) and sequencing of the Pre S1 region was done. Independent t test was used for comparison of means for the CD4 counts between the HIV mono-infected and HIV-HBV mono-infected. STATA was used to perform bivariate and multivariate analysis to determine factors associated with HBV infections using Poisson regression with significance set at P ≤0.05 and odds ratio with corresponding 95% confidence interval. Sample sequences were compared with published HBV genotypes sequences from GenBank and Phylogenetic trees were constructed using the NJ Plot software using a PHB file created through the DNA Database of Japan (DDBJ) to determine the HBV genotypes. Out of the 446 HIV positive participants screened, 126 (28.3%) were males and 320 (71.7%) females. The mean age of males was 44.93 years (SD ±10.16) while that of females was 42.22 years (SD ±10.88). Based on ELISA, 22/446 (4.93%) participants had HIV-HBV co-infection. Co-infection among males was 8.7% (11/126) compared to 3.4% (11/320) among females. Only 12 of the 22 positive samples by ELISA amplified via PCR. Out of the 12 HBV DNA positive samples 10 were successfully sequenced. Phylogenetic analysis of the Pre S1 region revealed that 9/10 (90%) samples belonged to genotype A while 1/10 (10%) belonged to genotype E. Males (p=0.028) and intravenous drug use (p= 0.008) were significantly associated HBV infections. The high prevalence (4.9%) of HBV among HIV patients attending Malindi Sub-county hospital is most likely highly driven by intravenous drug use and multiple sexual partners among the male gender. The distribution of HBV genotypes among HIV patients attending Malindi Sub-county hospital was similar to that previously reported in the general population. This study recommends for a continuous surveillance of HBV-HIV co-infections as well as analysis of HBV genotypes in different risk groups since they have an impact on disease management. Public awareness on the risk factors associated with the co-infection should also be emphasised.