Acute Pancreatitis due to pH-Dependent Mesalazine That Occurred in the Course of Ulcerative Colitis

Abstract

We report the case of a 26-year-old male who presented with acute pancreatitis during the course of treatment for pancolitic ulcerative colitis (UC) with a time-dependent mesalazine formulation, prednisolone and azathioprine (AZA). Despite a review of his clinical history and various tests, the cause of pancreatitis could not be determined. Since drug-induced pancreatitis was considered possible, administration of the time-dependent mesalazine preparation and AZA was discontinued, and conservative treatment for acute pancreatitis was performed. The pancreatitis promptly improved with these treatments, but drug lymphocyte stimulation test (DLST) for both the time-dependent mesalazine formulation and AZA was negative. A pH-dependent mesalazine formulation was given for maintenance therapy of UC. Subsequently, as the pancreatitis relapsed, drug-induced pancreatitis was strongly suspected. Administration of mesalazine was discontinued, and pancreatitis was smoothly in remission by conservative treatment. According to the positive DLST result for the pH-dependent mesalazine formulation and the clinical course, a diagnosis of pH-dependent mesalazine-induced pancreatitis due to this formulation was made. During the clinical course of UC, occurrence of drug-induced pancreatitis must always be considered.

Keywords: Mesalazine; Pancreatitis; Ulcerative colitis.

Fig. 1

Lower gastrointestinal endoscopy. a At the onset of UC. Sigmoid colon. Coarseness of the mucosa, disappearance of blood vessels seen through the mucosa, reddening, and erosion are observed continuously from the rectum to the ascending colon. b At the onset of the initial episode of pancreatitis. Sigmoid colon. Blood vessels are observed clearly through the mucosa, and no sign of inflammation is noted. c At the recurrence of pancreatitis. Sigmoid colon. No sign of inflammation is noted, as in b.

Fig. 2

Abdominal contrast-enhanced CT. a At the onset of UC. No abnormalities are noted in the pancreas. b At the onset of the initial episode of pancreatitis. The pancreas is mildly enlarged (arrow). c At the recurrence of pancreatitis. The pancreas is mildly enlarged, as in b (arrow).

Fig. 3

Clinical course.