Introduction: Necrotizing pancreatitis (NP) is a severe inflammatory process involving the pancreas, peripancreatic soft tissue, and mesenteric fat particularly in the transverse mesocolon and the root of the small bowel mesentery. Mesocolic involvement with this necrotizing process can directly and indirectly affect the blood supply to the colon resulting in ischemia, end-organ damage, and the need for colectomy. The aim of this study was to define the incidence and clinical outcome of patients requiring colectomy is the setting of NP.Methods: Records of all patients with acute pancreatitis (ICD-9 code 577.0) admitted to Indiana University Hospital between January 1996 and April 2008 were crossed-referenced with radiographic imaging data to identify patients with NP. Of 340 patients with NP, 37 patients required colectomy (Colectomy group). These patients were matched for age, gender, body mass index (BMI), and medical co-morbidities (diabetes, hypertension, coronary artery disease, pulmonary disease) with 37 NP patients who did not require colectomy (control group). Indications for and timing of colectomy were recorded, and clinical outcomes of the two groups were compared. Data were analyzed with Student’s t-test, Chi square and Fisher exact test. P value of less than 0.05 was considered statistically significant.Results: Eleven percent of all patients with NP (37/340) required colectomy. Indications for colectomy were: ischemia (20, 54%); fistula (8, 22%); intraoperative perforation (4, 11%); and other (5, 14%). Six percent of patients had colectomy prior to debridement, 40% required colectomy during initial pancreatic debridement, and 54% required the colectomy following the initial debridement. Outcomes for controls and colectomy patients are shown in the Table. Conclusions: These data show that: 1) colonic involvement is common in the setting of necrotizing pancreatitis, 2) ischemia is the most common indication for colectomy, and 3) patients requiring colectomy have significantly longer length of stay, readmission rate, and number of operations compared to those who did not require colectomy. In the setting of necrotizing pancreatitis, colectomy is common and portends a complex clinical course; clinicians must have a high index of suspicion for as well as an appreciation of the consequences of colonic involvement.

Group	Age	BMI	Length of Stay (LOS)	# Re-admissions	Total LOS	# Operations	# Debridment	Mortality
Control	54±3	28±1	24±1	0.9±0.2	30±2	1.8±0.2	1.3±0.1	2/37 (5%)
Colectomy	54±2	26±1	37±5*	3.0±0.6*	63±5*	3.9±0.4*	1.9±0.1*	7/37 (19%)

*p <0.01 vs control