Transient Colonic Intussusception Versus Colon Adenocarcinoma: A Case Report on Ultrasound Features in the Emergency Department.

Intussusception in adults is a rare pathology due to the telescoping of a bowel segment into a section adjacent to it. Almost all cases are linked to a pathological lead point, which is often a colorectal carcinoma where the intussusception involves the large intestine. Likely to occur in the same clinical setting, the differential diagnosis between intussusception and colon carcinoma by ultrasound in the emergency department can be quite challenging. We present a rare case of transient colonic intussusception with a well-differentiated colon adenocarcinoma as the lead point in a 43-year-old patient. The point of care ultrasound (POCUS) revealed the target sign characteristic of intussusception at the level of maximum pain, associated with a pseudokidney sign. However, the pseudokidney sign was indeed an adenocarcinoma of the ascending colon visualized by colonoscopy and per op.