A Unique Case of Autoimmune Hepatitis Developing in a Patient with Kikuchi-Fujimotoʼs Disease

Abstract

Purpose: We describe a 35 year old Hispanic woman with Kikuchi-Fujimoto's disease (KFD) who developed jaundice; abnormal liver function tests (LFTs) and was found to have developed autoimmune hepatitis (AIH). KFD (histiocytic necrotizing lymphadenitis) is a rare condition of unknown etiology first described in 1972 independently by Kikuchi and Fujimoto. It is a nonmalignant disease characterized by fever and cervical adenopathy and has a self-limiting course. This is the first reported case of a patient with histologically confirmed KFD developing AIH. One prior case report has described KFD occurring after AIH. A 35 year old Hispanic female was referred to our hepatology clinic due to complaints of worsening fatigue and jaundice for two weeks. Her past medical history was significant for KFD diagnosed 14 months ago via cervical lymph node biopsy. She was not on any treatment. On examination, the patient's vital signs were stable and she was afebrile. Abdominal examination was significant for mild tenderness in the right upper quadrant without any guarding or rigidity. Pertinent abnormal laboratory data included Aspartate aminotransferase/Alanine aminotransferase (AST/ALT) 1122/1247 U/L, Alakaline phosphatase 213 U/L, Gammaglutamyl transferase 216 U/L, total bilirubin 5.7 mg/dl, conjugated bilirubin 3.6 mg/dl, total protein 8.5 g/dl, albumin 3.3 g/dl, elevated Immunoglobulin G (IgG) level 2450 mg/dl and anti-smooth muscle antibody positive 1:640. The complete blood count, serum chemistry, viral hepatitis serologies, iron panel, ferritin, ceruloplasmin, alpha one antitrypsin, anti-nuclear antibody, anti-mitochondrial antibody and tissue-transglutaminase antibody were normal. Liver ultrasound was suggestive of mild diffuse fatty infiltration. A liver biopsy was performed which showed lymphoplasmacytic infiltrates, interface hepatitis, grade 4/4 inflammation, stage 2/4 fibrosis. The patient was diagnosed with AIH based on the clinical presentation, laboratory data and the biopsy results. The pre-treatment AIH score was 18. The patient was started on prednisone 60 mg orally daily for one week and there was significant improvement in LFTs. The steroid dose was tapered in the following weeks and the patient was noted to have complete normalization of LFTs and IgG by the fifth week of therapy. Azathioprine 75 mg daily was added with the tapering of the prednisone dose. Six months post-diagnosis, the patient is asymptomatic on a maintenance dose of prednisone 5 mg and azathioprine 75 mg daily. The coexistence of KFD and AIH is extremely rare in the reported literature. Our case is unique as it is the first reported case of histologically confirmed KFD who developed jaundice and was subsequently found to have AIH.