Epidemiological characteristics and clinical manifestations of hepatitis E virus infection in Bulgaria: A report on 20 patients.

Introduction: Hepatitis E is one of the leading clinical manifestations of acute viral hepatitis in developing countries. In industrialized countries, during the past several years, sporadic "autochthonous" cases of HEV infection have been increased.
Objective: The aim of this study was to analyze the epidemiological, clinical and laboratory features of HEV infection among patients hospitalized at the Department of Infectious Diseases in Military Medical Academy, Sofia, Bulgaria.
Methods: A retrospective study of 806 cases of acute viral hepatitis was performed at the Department of Infectious Diseases in Military Medical Academy, Sofia, Bulgaria, between December 2004 and September 2012.The etiological diagnosis was established by ELISA. The statistical analysis was performed using Excel 2007 (Microsoft, Redmond, Washington, USA) and SPSS Statistics 19.0 (IBM Corp., Armonk, NewYork, USA).
Results: Specific reaction to anti-HEV-IgM and anti-HEV-IgG antibodies were detected in 20 (2.48%) of 806 patients. The most observed clinical presentations were jaundice (85%), fatigue (85%), anorexia (65%), abdominal discomfort (55%) and fever (40%). The mean values of aspartate transaminase and alanine transaminase were 521 IU/l and 881 IU/l, respectively. The cholestasis was slight, marked with mean values of gamma-glutamyl transferase and alkaline phosphatase, respectively 418 IU/I and 486 IU/I.
Conclusion: We report twenty autochthonous sporadic cases of acute infection with HEV. The zoonotic etiology of the virus as well as the foodborne transmission of the infection is discussed. We found that aging and pre-existing underlying diseases are risk factors for a severe course of the HEV infection.