Clinical impact of influenza immunization in patients with liver cirrhosis

Background: Influenza vaccine is considered to reduce influenza-related morbidity and mortality in patients with underlying chronic medical conditions. Yet in liver cirrhosis, influenza vaccines have received little attention in determining the potential benefits. Objectives: We intended to evaluate the clinical benefits of influenza vaccination and clinical outcomes of influenza in patients with liver cirrhosis. Methods: We performed a controlled, prospective clinical trial of 311 cirrhotic patients, who were enrolled in October 2004. Among them, 198 patients were vaccinated with a trivalent influenza vaccine and the rest were not vaccinated. Both groups were followed with respect to the occurrence of influenza-like illness (ILI) until May 2005. Results: Overall incidences of ILI (p = 0.064) and culture positivity of influenza (p = 0.009) were remarkably higher in unvaccinated group compared to the vaccinated group. Most of the cirrhotic patients with influenza had fever (91.6%) and complained of myalgia (83.3%) without respiratory symptoms, which were not typical clinical presentations of influenza. Influenza vaccination also decreased influenza-related complication rates in patients with liver cirrhosis. Conclusion: Influenza vaccination should be recommended to all cirrhotic patients. High suspicion is required for early diagnosis and antiviral treatment, allowing for the frequent hepatic decompensation among cirrhotic patients.