Acute pancreatitis caused by severe Legionella pneumophila infection.

We report three cases of severe community-acquired Legionella pneumophila pneumonia with acute pancreatitis. Pancreas involvement is unusual. The clinical presentations consisted of painless pancreatitis with only elevation of serum pancreatic enzymes (case 1), tender abdomen with edematous pancreas on computed tomography scan (case 2) and necrosis (case 3). We discuss the possible mechanisms of L. pneumophila associated acute pancreatitis for which the pathophysiology is still undetermined: infection, toxin release or cytokine secretion.