The impact of HIV infection and men who have sex with men status on hepatitis A infection: The experience of two tertiary centres in Northern Italy during the 2017 outbreak and in the 2009-2016 period

Hepatitis A is a self-limiting infection representing the most common cause of viral hepatitis worldwide. Despite being a low incidence region, in the European Union, an increasing number of cases have been reported since summer 2016, resulting in a large outbreak in 2017, involving mainly men who have sex with men (MSM). Some reports described a different clinical course of hepatitis A virus in patients infected by human immunodeficiency virus (HIV) or MSM. We consecutively collected all the hospitalized cases of hepatitis A referred to two tertiary centres in Northern Italy in 2017 and retrospectively analysed the electronic records of the 2009-2016 period (pre-2017). We evaluated demographics data, risk factors, comorbidities and laboratory results to see whether MSM status or HIV infection influenced the disease. Overall, 117 cases were identified in 2017:107 (91%) were male, 78 reported themselves as MSM (66%) and 17 (14.5%) were infected by HIV. For the pre-2017 period, 48 cases were reported: 29 (60%) were male and 3 (6.2%) were infected by HIV. After stratification for HIV infection, MSM status and occurrence period, no differences were found in aspartate aminotransferase, alanine aminotransferase, γ-glutamyl transpeptidase; bilirubin, alkaline phosphatase and bilirubin values, hospitalization length, HIV viral load and CD4+cells count. HIV-positive patients presented a higher number of patients with INR>1.5 at admission. MSM status and HIV infection did not affect neither the clinical course nor the severity of hepatitis A.