Drug induced autoimmune hepatitis: a single center experience. Yilmaz Bilgic 1* , Hakan Harputluoglu 2 , Cengiz Yilmaz 1 , Nese Karadag 3 , Yasir Furkan Cagin 1 , Sami Akbulut 4 , Yüksel Seckin 1 , Orkide Kutlu 5 , Oguzhan Yildirim 1 , Murat Harputluoglu 1 1 Department of Gastroenterology, Inonu University, Malatya, Turkey 2 Department of Medical Oncology, Inonu University, Malatya, Turkey 3 Department of Pathology, Inonu University, Malatya, Turkey 4 Department of General Surgery, Inonu University, Malatya, Turkey 5 Department of Internal Medicine, Inonu University, Malatya, Turkey Abstract Objective: Many drugs such as minocycline, nitrofurantoin, halothane, non-steroidal anti-inflammatory drugs, anti TNF (Tumor Necrosis Factor) antagonists can induce the autoimmune hepatitis. Herein, we aimed to assess patients suffering from drug induced autoimmune hepatitis who were hospitalized with acute hepatitis like transaminase elevations to our clinic between 2009-2015. Method: The patients were determined using simplified diagnostic criteria of the International Autoimmune Hepatitis Group. Results: We determined 9 patients whose score were compatible with the diagnosis of Autoimmune hepatitis (AIH). Three patients were older than 50, and six patients were between 19 and 31. Seven of nine patients were female. The drugs thought responsible for AIH were as follows; ciprofloxacin alone, amoxicillin plus nimesulid, amoxicillin plus ornidazole, amoxicillin alone, a combined oral contraceptive pill plus a mixture of natural drugs, metronidazole plus dexketoprofen, ramipril plus metronidazole, levofloxacin alone and venlafaxine plus mianserin for each case. Five of nine patients had been followed up conservatively upon discontinuation of drug(s) and did not need any treatment during hospitalization and resolved spontaneously. Four patients received immunosuppressive treatment which was withdrawn in 3 of those 4 patients after 3 to 6 months upon remission without relapse. Conclusion: Drug induced autoimmune hepatitis (DIAIH) can be presented with acute hepatitis of unknown etiology. Female sex seems to be a risk factor for DIAH. Treatment decisions should be given according to patient’s clinical status and follow up at acute presentations. There can be no treatment need, but, when needed generally a short course of immunosuppressive treatment can be sufficient. Keywords: Drug, Autoimmunity, Hepatitis. Accepted on January 20, 2017 Objective Autoimmune hepatitis (AIH) is an inflammatory liver disease that predominantly affects women and is characterized by hypergammaglobulinaemia, circulating autoantibodies, interface hepatitis on liver histology, and a favourable response to immunosuppression [1]. AIH may present with a variety of clinical manifestations, ranging from asymptomatic disease to fulminant liver failure. Early diagnosis is important in all instances because the disease can be highly responsive to immunosuppressive therapeutic options. Left untreated, the disease is associated with high morbidity and mortality [2]. The pathogenesis of AIH postulate an environmental agent that triggers a cascade of T-cell-mediated events directed at liver antigens in a host genetically predisposed to this disease, leading to a progressive necroinflammatory and fibrotic process and ultimately cirrhosis in the liver. Environmental agents assumed to induce AIH have not been delineated, but viruses, certain drugs and herbal agents may lead to AIH [3]. Drug induced autoimmune hepatitis (DIAIH) has been reported to be caused by several drugs. Minocyline, nitrofurantain, halothane, tienciclic acid, dihydralazine, methyldopa, ornidazole, alpha and beta interferon, statins, fibrates and anti- TNFα agents are the examples of reported drugs that may induce AIH [3-5]. AIH is a clinicopathological diagnosis and for an objective diagnosis scoring systems are used. In 1993, the International Autoimmune Hepatitis Group published first scoring system for AIH [6] with a revision released in 1999 [7]. A simplified scoring system was published in 2008 [8], ISSN 0970-938X www.biomedres.info Biomed Res- India 2017 Volume 28 Issue 15 Biomedical Research 2017; 28 (15): 6528-6532 6528