A rare cause of painless obstructive jaundice in the elderly – a case series

Summary: A series of two case reports discusses the differential diagnosis of painless jaundice in the elderly and points to autoimmune pancreatitis as one of its rarer causes. In search for the cause, the first step is to rule out the malignant origin of the obstruction using the clinical picture, imaging examinations, and EUS-guided biopsy. An imaging examination can initially point to the possibility of autoimmune pancreatitis, but in the case of focal pancreatic involvement the distinction from cancer is unreliable. Elevated concentration of IgG4 antibodies can further increase the probability of IgG4-associated pancreatitis. Histological examination of the pancreas will help reveal typical features of autoimmune pancreatitis such as lymphoplasmacytic infiltrate, storiform fibrosis, obliterating phlebitis and increased number of IgG4 positive plasma cells. Once the diagnosis is probable, it is advisable to start a treatment with steroids. A quick decrease in cholestatic markers and bilirubin is typical. Patients with autoimmune pancreatitis require long-term follow-up, to adjust the treatment in case of relapses, the risk of developing exocrine or endocrine insufficiency, and in case of IgG4 associated disease due to the risk of other organ systems involvement. The risk of pancreatic cancer is still a matter of discussion. Key words: autoimmune pancreatitis – IgG4 – obstructive jaundice – case report