Acute pancreatitis with pseudocyst formation in a patient with polyarteritis nodosa.

Polyarteritis nodosa (PAN) is a term that includes patients with necrotizing inflammation of medium sized arteries, and excludes those with microscopic vessel involvement. Its manifestations are protean and include constitutional symptoms such as fever, malaise, weight loss, myalgia, peripheral neuropathy, rash, and gut and renal involvement. Although gastrointestinal manifestations have been noted in up to a third of patients with PAN, clinical presentation with pancreatic involvement has been reported only rarely. We describe a patient with PAN who developed acute pancreatitis with pseudocyst formation as well as infarcts in the spleen and liver.