This retrospective study characterized the demographic, clinical, and laboratory data of patients with IBD in whom AP preceded disease onset, and compared the presentation between children and adults. Pediatric and adult patients presenting with AP as the first symptom of IBD over 10 years at 7 university hospitals were identified. AP preceding the diagnosis of IBD was found in 10 of 460 pediatric patients with IBD (2.17%), compared with only 2 of 3500 adults (0.06%). Eight children had colonic disease (4 Crohn disease, 4 ulcerative colitis [3 pancolitis]). Mean amylase level was 1419 (range 100 to 1370). Three children (30%) had mildly elevated transaminases. Median time between onset of first episode of AP in relation to onset of IBD was 24 (range 1-156) weeks. AP most commonly presented with abdominal pain. IBD presenting as AP was more frequent among the pediatric population with IBD in comparison to adults, and it was more common in patients with colitis than in those with ileal disease, suggesting that patients with idiopathic AP should be investigated thoroughly for a possible diagnosis of IBD. (J Pediatr Gastroenterol Nutr. 2011 Apr 7. [Epub ahead of print]) PMID: 21478760.