Seroprevalence of human immunodeficiency virus, hepatitis B and C viruses among haemodialysis patients in two newly opened centres in Cameroon

Introduction Haemodialysis (HD) patients are potentially susceptible to infection with blood borne viral agents especially; Human Immunodeficiency Virus (HIV), hepatitis B (HBV) and hepatitis C Viruses (HCV), compared to the general population. We described their epidemiology in two newly created haemodialysis units in Cameroon: the Buea and Bamenda haemodialysis centres. Methods A cross sectional study: included were patients who had spent at least three months in haemodialysis. HBV, HCV and HIV serologies were determined and patients' characteristics extracted from patient's records. Results We included 104 participants (44 in Buea and 60 in Bamenda). Mean age was 48 years and 65.4% were men. Median duration in dialysis was 14 months. One of the three viral markers was present in 40.1% of patients. The hepatitis B surface antigen, anti-HCV and anti-HIV antibody prevalence were respectively 10.6%, 19.2%, 13.5%. A history of sexually transmitted infection was the only variable associated with anti-HIV antibody positivity Conclusion The sero-prevalence of HBsAg, HCV and HIV are high in the two centres. HIV prevalence may have reflected its etiology as a cause of ESKD. HCV remains a cause for concern and needs further evaluation. There is urgent need for the implementation of preventive and control measures.


Hepatitis B Virus (HBV), Hepatitis C Virus (HCV) and Human
Immunodeficiency Virus (HIV) infections are major public health problems worldwide. It is estimated that over 350 million people are chronically infected with HBV [1], more than 185 million with HCV [2] and over 35 million with HIV [3]. The greatest burden of disease is in low and middle income countries. These viruses singly or as coinfections can induce hepatic inflammation which potentially results in progressive fibrosis leading to cirrhosis and hepatocellular carcinoma. Haemodialysis (HD) patients are potentially susceptible to infection with these blood borne viral agents (HBV, HCV, HIV) compared to the general population making them a persistent public health concern as they are a cause of increased morbidity and mortality [4,5]. The prevalence of HBV in dialysis facilities in Western Europe, United States of America and Japan has been shown to range between 0-6.6% [6,7]. By contrast in Asia Pacific it ranged from 1.3 to 14.6% [8]. The prevalence of HCV in HD varies greatly ranging from a low 1% to as high as 70% being generally below 5% in high income countries [9]. To address the growing demand for management of End stage Kidney Disease (ESKD), HD services were progressively decentralised from 2009 to second level regional hospitals. There are now a total of seven centres. In the Douala HD centre, the largest and busiest in Cameroon, the prevalence of HBV and HIV in 166 HD patients was 7.8% and 10.8% respectively [11]. However, in this same centre and at around the same time frame, baseline prevalence of HBV, HCV and HIV in ESKD patients prior to commencing HD was 6.2%, 20.6% and 9.3% respectively [12].
Focus on the prevalence of blood borne viruses in HD centres and the determination of their risk factors will enable health planners in Cameroon to operate more effectively, to reduce disease prevalence and ultimately reduce rates of morbidity and mortality. Initial and regular evaluation may play an important role especially in the new centres which have limited experience with HD. The aim of this study was to determine the prevalence and factors associated with HBsAg, anti-HCV and HIV antibodies among HD patients in two newly created HD centers in Cameroon. Yaounde is over 300km from each of the centres.

Methods
Page number not for citation purposes 3 Study population patients: In both centres, all patients on maintenance hemodialysis for at least three months were eligible for this study. Informed and written consent was obtained from each participant. Data was collected, using a pre-tested structured questionnaire, by a trained final year medical student. Sociodemographic data (age, residence, marital status and educational level), potential risk factors for acquiring blood borne infections (blood transfusions, previous surgery, tattoos, history of sexually transmissible infections (STI) and duration on HD) were noted and patient files were used to complete the information and clinical data.
Laboratory procedures; five millilitres of blood was collected by a nurse using standard procedures for peripheral venipuncture from each patient before commencement of the HD session. This was to avoid interaction of the blood with heparin which is given during dialysis. We screened for HIV using immunochromatographic tests Diagnostics product GmbH Marburg, Germany). Ethical clearance was sought and obtained by the institutional review board (IRB) of the Faculty of Health Sciences, Buea. Administrative clearance was also given by the South West and North West Regional delegates of public health and the chief medical officers for the Buea and Bamenda regional hospitals.

Statistical analysis:
Results are presented as count (percent). We categorised age in groups of 20 years and used the Chi 2 or fishers exact test to look for association between HbsAg, anti-HCV and anti-HIV antibodies and other categorical variables. We also used a 2 sample proportion test to compare the prevalences of HbsAg, anti-HCV and anti-HIV antibodies in the two regions. The level of significance in hypothesis testing was set at the level of 5%. Results were analysed using STATA 12 (Stata Corporation, college station, Texas, USA).
Ethical considerations: Ethical clearance was obtained from the institutional review board of the Faculty of Health sciences, University of Buea. Administrative authorization was sought and obtained from the South West and North West Regional delegates of public health and the chief medical officers for the Buea and Bamenda regional hospitals. Confidentiality, anonymity and privacy of all participants were guaranteed at all levels of this study. Written consent was provided by each and every participant.

Results
We included 104 participants in this study (44 in Buea and 60 in Bamenda) and their mean age was 48 (sd: 16) years. Table   1 Table 2 shows the prevalences of HbsAg, anti-HCV and anti-HIV antibodies by sociodemographic, comorbidities and potential risk factors for acquiring these infections in the participants. Diabetes was associated with anti-HCV antibody positivity, whilst age and history of STI were both associated to anti-HIV antibody positivity. No association was found between HBsAg positivity and all the variables tested.

Discussion
The HD procedure per se, as well as disturbances in both innate and adaptive immunity significantly contributes to increased susceptibility to infections in patients on maintenance HD. Among

Conclusion
The sero-prevalence of HBsAg, HCV and HIV are high in the two newly opened HD centres studied in Cameroon. While the HBV prevalence in chronic HD patients may have reflected the burden of the disease in the general population, that of HIV may have reflected its etiology as a cause of ESKD. HCV in HD remains a cause for concern and needs to be further evaluated. There is need for multicentre studies in Cameroon as it will give a better picture of the burden of these blood borne viral infections in HD. This improved understanding will help to emphasize the urgent need for

Acknowledgments
We would like to express our gratitude to Elvis Temfack who was initially involved with the data analysis, Gobina Ronald and Kegne who were the medical officers in charge, the healthcare teams and all the patients of the Buea and Bamenda HD centres, for their cooperation. Table 1: Baseline characteristics of the study population (N=104)