High level of persistent liver injury is one of clinical characteristics in treatment‐naïve acute onset autoimmune hepatitis: experience in a community hospital

Background There is, as yet, no gold standard for making the diagnosis of acute onset autoimmune hepatitis (A-AIH). Novel histological characteristics have been reported, but etiologies other than AIH could show similar histological pattern. We attempted to determine what clinical characteristics we should consider as A-AIH different from other etiologies, and to whom histological characteristics should be applied for the diagnosis. Methods Clinical, biochemical, immunological and pathological features of 46 patients (35 women, mean age 55.9 ± 14.2 years) with non-severe A-AIH admitted to a community hospital between 2001 and 2015 were analyzed. Results Immunoglobulin G level was normal in 28%, and anti-nuclear antibody titer was < × 80 in 28%. Liver histology of 49% showed acute form and 51% chronic one. Centrilobular necrosis/collapse and/or plasma cell accumulation, rosette formation were characteristic for A-AIH. High levels of alanine aminotranferase persisted in 21 patients who could be observed for equal to or more than 4 weeks before the start of treatment. Conclusions Long persistence of high levels of alanine aminotransferase would be one of clinical features for considering A-AIH along with conventional features. Histological diagnostic features should be applied for such patients. Guidelines for diagnosing A-AIH should be urgently drawn up.