Isoniazid-Induced Acute Pancreatitis with Pseudocyst

Numerous medications have the potential to induce acute pancreatitis. However, isoniazid-induced acute pancreatitis is extremely rare. Drug-induced acute pancreatitis can be diagnosed by improvement after stopping the drug and recurrence of pancreatitis when rechallenged. We present a case of severe acute pancreatitis accompanied by multiple large pseudocysts after isoniazid treatment for pulmonary tuberculosis. We confirmed that isoniazid induced pancreatitis by rechallenging after treatment cessation. Most previous reports of isoniazid-induced pancreatitis have been clinically mild forms, and the patient fully recovered with supportive management. However, this case presents severe and permanent pancreatic damage that developed with 5 weeks of isoniazid treatment. When a patient presents with manifestations of pancreatitis during treatment of tuberculosis that includes isoniazid, the physician should consider isoniazid-induced pancreatitis. (Korean J Med 2012;82:594-598)