Susceptibility to hepatitis A in patients with chronic liver disease due to hepatitis C virus infection: missed opportunities for vaccination.

Hepatitis A virus (HAV) superinfection is associated with a high risk of liver failure and death in patients with underlying chronic liver disease. Although HAV vaccination is recommended for all patients with chronic hepatitis C virus (HCV) infection, little is known about adherence to these recommendations in clinical practice. The aims of this study were to determine the frequency of HAV testing and vaccination among patients with chronic HCV infection. We conducted a retrospective cohort study of 1,193 patients diagnosed with chronic HCV infection over a 1-year period. During 1,646 person-years of follow-up, patients were seen by their primary care provider a median of 10.0 times (interquartile range, 4.0-20.0). HAV antibody testing was performed in 640 subjects (53.6%), and 317 (49.5%) of those tested were susceptible (HAV antibody negative). Only 94 of the 1,193 patients (7.9%) received the HAV vaccine, including 26.8% of the 317 susceptible patients, 0.9% of the 323 patients who were already immune to HAV, and 1.1% of the 553 subjects who were never tested. Among the 94 vaccinated patients, 45 received only one dose of the vaccine. Three of the unvaccinated patients developed acute HAV infection during follow-up, and 1 of them died of acute liver failure. In conclusion, despite published recommendations to vaccinate against HAV in patients with chronic HCV infection, we found that HAV testing and vaccination rates were low in clinical practice. Public health programs to increase awareness about HAV vaccination in patients with chronic liver disease are needed.