In solid organ transplant (SOT) recipients, hepatitis E virus (HEV) can cause potentially life-threatening chronic hepatitis E, which can be treated efficiently with ribavirin (1-3).Kamar et al reported a series of 69 SOT recipients who acquired acute HEV infection after transplantation (4). Immunocompetent symptomatic patients usually show viremia of <30 days' duration (5). In the study by Kamar et al, however, 41 patients (59%) developed a persistent infection lasting >6 months (4). In no case was HEV clearance observed between months 3 and 6 after infection; therefore, the authors defined chronic HEV infection as persistence of HEV viremia for >3 months (4).In contrast to these previous data, we describe a case of spontaneous clearance of HEV infection after >3 months in a SOT recipient.A woman aged 47 years presented at our outpatient clinic for a routine annual checkup. She had undergone liver transplantation for Budd-Chiari syndrome 7 years earlier.Her immunosuppression consisted of tacrolimus and mycophenolate mofetil. At the time of presentation, she did not have any clinical symptoms, and transaminases, bilirubin and g-glutamyl transferase were within the normal range.Since 2012 we have routinely tested all liver transplant recipients presenting for annual checkup for HEV RNA by polymerase chain reaction. This patient tested positive unexpectedly, with a high HEV RNA load ( Figure 1A). She had tested negative 12 months earlier. Because the asymptomatic patient had a realistic chance of clearing the assumed acute infection, we decided not to treat the infection immediately but rather to wait 3 months until the patient conformed to the definition of chronic hepatitis E.Over the next 3 months, the viral load was stable and the transaminases increased only temporarily, with maximum values of twice the upper limit of normal ( Figure 1B). Six weeks after diagnosis of HEV infection, the patient suddenly developed flu-like symptoms, including weakness, arthralgia and nausea. These symptoms were followed by an HEV-specific B cell response, indicated by an increase of anti-HEV IgM and IgG OD levels within the semiquantitative Euroimmun assay (Euroimmun, Luebeck, Germany) ( Figure 1A). Although symptoms disappeared spontaneously, the anti-HEV level increased and the HEV viral load declined, followed by clearance of infection. Conclusions(i) The previously suggested definition of chronicity of HEV infection by viral persistence of >3 months is not sufficient. In immunosuppressed patients, spontaneous clearance can occur after a time period of >3 months. Apart from a short episode of symptoms (arthralgia and nausea) immediately prior to viral clearance, the patient was asymptomatic during the whole viremic period. Analogous to infections with hepatitis B virus or hepatitis C virus, we define chronic hepatitis E as persistent viremia for >6 months.

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Changes of central venous pressure due to changes of PEEP and positioning were not correlated with changes of venous hepatic blood flow parameters as measured after equilibration. Strategies aiming for low central venous pressure cannot be supported by these results. However, before ruling out low-CVP-strategies during liver resections these results should be confirmed by further studies.