Transverse Colonic Intussusception in an Adult

A 79-year-old man presented with several days of intermittent sharp abdominal pain and melena. Computed tomography revealed transverse colonic intussusception with a hepatic flexure lipoma acting as the lead point (Fig. 1). Symptoms resolved following right hemicolectomy.

Figure 1.

Coronal CT scan showing proximal colon (A) within the transverse colon (B) with a hepatic flexure lipoma (C) acting as the lead point and stool and dilated bowel proximal to the intussusception (D)

Intussusception occurs approximately 20 times more frequently in children than adults, but still accounts for up to 5% of adult bowel obstructions.^{1, 2} Any condition that disrupts normal peristalsis increases the risk of intussusception; however, most adult cases are caused by a lead point such as a neoplasm, post-surgical adhesion, intestinal ulcer, or diverticulum.¹ These lead points can be caught in an adjacent segment of bowel and then pulled further forward by peristalsis.¹ As invagination increases, the affected bowel becomes edematous and, if untreated, blood flow can be compromised leading to ischemia and necrosis.² Approximately 90% of adult cases have an identifiable cause and abdominal CT is considered the gold standard for diagnosis.¹ In contrast to pediatric cases where nonoperative reduction is sufficient, adult intussusception often requires surgical intervention both to relieve the obstruction and to aid in characterizing neoplastic lead points as benign or malignant.