PURPOSE: Colonoscopic splenic injuries are rare. We reviewed our institutional experience with splenic rupture as a result of colonoscopy to define the incidence and management. METHODS: Review of all patients from 1980 through June 2008 sustaining a splenic injury during colonoscopy. RESULTS: Four patients (of 296,248 colonoscopies) sustained a splenic injury directly from colonoscopy performed at our institution (incidence 0.001%). Three additional patients were treated at our tertiary referral center after splenic injury from colonoscopy performed elsewhere. Follow-up was complete in all patients over a median of 22 months (range 1-164 months). The seven patients ranged in age from 40 to 70 years old. Indications for colonoscopy included diarrhea (n=3), abdominal pain (n=2), screening (n=1), and colonic polyps (n=1). Only 2 patients had a history of prior abdominal operation(s). All patients had an adequate bowel preparation and only 2 colonoscopies were described as difficult. The most common symptom of splenic rupture was abdominal pain (n=4) with a mean decrease in hemoglobin of 6.5 g/dl (range 4.5 - 8.5 g/dl). Six patients received a mean of 5.5 units of packed red blood cells (range 2-14 units). Splenic injury was diagnosed by computed tomography (CT) in 5 patients. Two (of the 5) CT scans were performed at our institution and available for review showed grade III splenic lacerations. All patients were managed with emergent splenectomy upon diagnosis; 6 within 24 hours of the index colonoscopy, and 1 who presented more than 24 hours after colonoscopy. No patients had pre-existing splenic disease on surgical pathology. There were no post-operative complications or deaths. The mean duration of stay was 10 days (range 7-15). CONCLUSION: Splenic injury during colonoscopy is a rare but serious complication. Patients present with abdominal pain, a precipitous decrease in hemoglobin and require emergent splenectomy due to the acute nature of their presentation. Splenic injury can occur in the absence of splenic pathology or adhesions from prior celiotomy.