Beta-sitosterol-induced Acute Pancreatitis: A Case Report and Review of the Literature.

While drug-induced pancreatitis from corticosteroids has been well described in the medical literature, the exact mechanism is unclear. We present the first reported case of drug-induced pancreatitis from beta-sitosterol, a naturally occurring plant sterol structurally similar to cholesterol, obtained primarily through Western diet and supplementation. A 57-year-old male with a history of situs inversus and benign prostatic hyperplasia presented from an outside facility with a two-day history of worsening epigastric pain radiating to the right upper quadrant. Lipase was markedly elevated at 572 U/L. CT scan and ultrasound of the abdomen were remarkable for acute pancreatitis with acute necrotic collections and normal appearing gallbladder and bile ducts without the presence of gallstones. The patient was managed with aggressive intravenous hydration and supportive management and had resolution of symptoms. At his follow-up appointment, the patient disclosed that he had started a new herbal supplement, beta-sitosterol, on the morning after his symptoms began. Abdominal magnetic resonance cholangiopancreatography obtained at follow-up appointment showed interval resolution of pancreatitis and normal biliary anatomy. In the absence of classical risk factors for acute pancreatitis, a diagnosis of drug-induced pancreatitis secondary to beta-sitosterol was made. The patient was advised to avoid beta-sitosterol, and thus continued to remain asymptomatic. We describe the first reported case of drug-induced pancreatitis from beta-sitosterol, a common phytosterol found in many over the counter supplements worldwide. After a thorough workup to exclude other causes, our case demonstrates consistent resolution of symptoms and pancreatic enzymes along with normal imaging following discontinuation of the offending agent.