Prevalence of previous hepatitis A virus infection in renal transplant patients with hepatitis C: evidence of persistent anti-hepatitis A virus immune response

Data concerning the prevalence of hepatitis A virus (HAV) infection among kidney transplant recipients are scarce. There is little information concerning natural immunity acquired after acute HAV infection. In most renal transplant recipients, anti-HAV antibodies are not detectable after vaccination; it is reasonable to suppose that immunosuppressive therapy interferes with the immunity. The objective of this study was to evaluate, in an endemic area, the prevalence of anti-HAV immunoglobulin (Ig)G in renal transplant recipients with chronic hepatitis C virus (HCV) infection. The prevalence of anti-HAV IgG was assessed in 40 HCV-positive renal transplant recipients. This group showed a 90% prevalence of previous HAV infection. These findings suggest that in an endemic area, the prevalence of previous HAV infection is high, even among immunosuppressed patients. HAV antibodies acquired after natural infection are detectable even after the onset of immunosuppressive therapy. These data should be considered when renal transplant recipients are considered for HAV vaccination. Prevaccination screening of renal transplant recipients must follow the same guidelines as those for immunocompetent subjects.