E04. Hepatitis E Infection in Inflammatory Arthritis

Abstract

Background: MTX is the most commonly used DMARD for management of inflammatory arthritis. As part of its monitoring, liver function tests are regularly checked to ensure there is no liver damage. Very often in clinical practice, the liver function tests can become abnormal, which results in attributing the abnormality to MTX, and various investigations are performed including checking for active HBV and HCV infection. Although rare in developed counties, the possibility of HEV infection must be kept in mind in patients on immunosuppression when there is an unexplained sudden increase in liver enzymes which this case report illustrates. Methods: We report two cases of abnormal liver function tests which were detected as part of routine blood monitoring performed every 3 months due to being on MTX monotherapy. The first case is of a 68 year old woman with seropositive erosive RA for 8 years and had been on stable dose of 12.5 mg once weekly for last 6 years. It was noted that she had greater than tenfold elevation of aspartate and alanine aminotransferase levels and moderate elevation of alkaline phosphatase. She felt a bit tired but otherwise well. The other case is of a 32 year old Caucasian man who was on stable dose of 20 mg once weekly for 2 years for PsA. He also felt more tired with reduced appetite and was found to have a >10-fold elevation in alanine transaminase and aspartate transaminase levels. Results: In both cases, MTX was stopped and it took around 2 months for the liver enzymes to go back to previous normal levels. In both cases, there was no history of prior travel abroad when the liver tests became abnormal. Initial non-invasive liver screen was unremarkable along with normal liver US and HBV and HCV test serology; both patients were subsequently diagnosed with having HEV infection which was confirmed by positive PCR detection and positive IgM result. In both cases, following discussion with hepatologist MTX was reintroduced once the liver enzymes had become normal with no evidence of abnormality in liver enzymes later on. HEV infection happens rarely in UK but the incidence is going up due to consumption of undercooked pork and travel to developing countries. There are no reports of chronic HEV infection following immunosuppression and outcome of HEV infection is usually favourable. Conclusion: These cases highlight the importance of arranging investigations looking for HEV infections even if there is no history of travel abroad and not attributing all liver enzyme abnormalities to MTX. The diagnosis of acute hepatitis E should be considered in patients with inflammatory arthritides with acutely raised liver enzymes who are on immunosuppressants. Disclosure statement: The author has declared no conflicts of interest.