Image: Colonic Hematoma Complicating Pediatric Colonoscopy

**Background:** Colonic intramural hematoma is a rare complication of diagnostic colonoscopy, with only a handful of reported cases in adults and even fewer in children. In pediatric patients, colonic hematomas have been associated with accidental or nonaccidental trauma, bleeding disorders, and anticoagulant therapy. This case is one of the first reported instances of colonic hematoma complicating diagnostic colonoscopy in a pediatric patient. The lack of awareness and published images of this complication can lead to misdiagnosis and unnecessary extensive evaluations.

**Methods:** This is a case report of a 6-year-old girl with chronic constipation who was referred for intermittent mass per rectum. A colonoscopy was performed to exclude a rectal polyp. The procedure was complicated by poor bowel preparation and looping of the colonoscope in the redundant sigmoid colon, resulting in poor visualization and a prolonged but successfully completed procedure. On withdrawal of the colonoscope, four discreet vascular lesions were observed between the splenic flexure and sigmoid colon. These lesions were raised, purple in color, interspersed with normal colonic mucosa, and not actively bleeding. The initial impression was angiodysplasia with concern for blue rubber bleb nevus syndrome. Subsequently, coagulation studies, computerized tomography angiogram of the chest and abdomen, esophagogastroduodenoscopy, and capsule endoscopy were performed and were all normal. A repeat flexible sigmoidoscopy three months later was normal, and the previously visualized lesions were no longer present.

**Key Results:** The vascular lesions seen during the initial colonoscopy were most likely intramural hematomas resulting from trauma secondary to looping of the colonoscope and loop reduction maneuvers. The lesions resolved spontaneously without intervention, as confirmed by normal repeat sigmoidoscopy at three months. The case highlights that no cases of colonic hematoma have been reported in the Pediatric Endoscopy Database System-Clinical Outcomes Research Initiative database (personal communication from Dr Douglas Fishman, June 15, 2021). The misdiagnosis led to an extensive evaluation for angiodysplasia, which could have been avoided if the hematoma had been correctly identified.

**Clinical Implications:** This case underscores the importance of recognizing colonic intramural hematoma as a potential complication of diagnostic colonoscopy in children, especially when technical difficulties such as looping occur. Awareness of this entity can prevent unnecessary and invasive diagnostic workups for conditions like angiodysplasia or blue rubber bleb nevus syndrome. The spontaneous resolution of the hematomas without intervention suggests a benign course, but clinicians should be vigilant for this complication to avoid misdiagnosis and associated patient anxiety and healthcare costs.