Occult hepatitis B virus infection among chronic hemodialysis patients in Alexandria, Egypt.

The prevalence of end-stage renal disease has increased dramatically in developing countries. Hepatitis B virus (HBV) infection is a global health problem that represents a significant co-morbidity event that has led to outbreaks of hepatitis B. There are inadequate data concerning occult HBV infection among Egyptian chronic hemodialysis patients. This study aimed to detect occult HBV infection among chronic hemodialysis patients in Alexandria, Egypt. A cross-sectional study was performed on 100 patients with end-stage renal disease that received maintenance hemodialysis and had tested negative for HBV surface antigen. Blood samples were collected before the initiation of hemodialysis. Sera were tested for hepatitis C virus (HCV) and hepatitis B core (HBc) antibodies using ELISA, and HBV DNA was detected by SYBR Green real-time PCR using specific primers for the s and c genes and by nested PCR using pol gene-specific primers. The serum activity of alanine and aspartate aminotransferase (ALT and AST) were also measured. Anti-HCV and anti-HBc antibodies were detected in 34% and 48% of patients, respectively, and 70.6% of anti-HCV positive patients were also positive for anti-HBc antibodies. This association was statistically significant (p=0.001). HBV DNA was detected in 32% of the hemodialysis patients. A significant association was determined between the presence of HBV DNA and anti-HCV positivity (p=0.021). Aminotransferases were elevated in 21% of the studied patients, more often in patients with positive anti-HCV profiles than in patients negative for anti-HCV (p<0.05). In conclusion, the serological markers of HBV infection should be verified with molecular tests to investigate possible occult infections, especially among anti-HBc-positive hemodialysis patients, to improve our understanding of their clinical, laboratory, and epidemiological characteristics.