Prevalence of HBV and Associated Genetic Polymorphism in Chronic HBV Patients of KPK-Region in Pakistan

Abstract

Hepatitis B virus (HBV) infection is a global public health concern that affects more than 2 billion people throughout the world. Among these 400 million develop chronic hepatitis infection. In year 2015 alone, 257 million individuals were living with chronic HBV infection (WHO data) while 887000 fatalities were reported due to HBV hepatocellular carcinoma and cirrhosis. Although, chronic hepatitis B (CHB) infection is rare in developed countries, in Pakistan HBV morbidity and mortality is high. One important aspect of this higher morbidity and mortality is host genetic factors. This study consists of two parts; First, 946 blood samples were screened for the prevalence of HBV and coinfection of other hepatitis viruses (HDV & HCV) in general population. Overall percentage of HBsAg-positive patients remained 22.41 % (prevalence: 224.1011 000; CI: 0.197 5 ± 0.250 7) with the highest incidence rates among relatively younger age groups (20-29 years). The prevalence of HBV-HDV co-infection was found to be 46.75/1000; CI: 0.0318 ± 0.062, while HBV-HCV co-infection was found 7.55% (16/212). In HBsAg-positive patients, anti-HBc-total was detected in 86.79%, while 25% were positive for anti-HBc-immunoglobulin M. among these patients, HBV DNA was detected in 64.13% and 10.85% were co-infected with HDV. Different symptoms were associated with the prevailing infection, including malaise (62%), anorexia (66%) and fatigue (73%). The most commonly associated symptom was abdominal discomfort. Among these patients, certain risk factors, including surgery, visit to dentist and intravenous infusions were frequently associated with the infection (X2 = 95.23; df= 11 ; P < 0.000 1). In the second part of this study, 354 blood samples (240) HBV infection, 57 clearance and 57 healthy controls) samples were collected. Based on different clinical parameters patients were categorized into healthy, spontaneously recovered, chronic with steatosis and without steatosis groups. Among 240 chronic HBV patients, 44 (18%) were found to have steatosis and n=196 (82%) had no steatosis. The gender-based distribution for the studied participants revealed that 70% were males and 30% females. Although the median age of the recruited patients was 29 years. Some common signs and symptoms among studied patients including abdominal discomfort, anorexia, fatigue, and malaise were witnessed.