Adult colo-colic intussusception caused by colonic lipoma: a rare case report diagnosed by emergency point care of ultrasound
A 47 years old male without any underlying diseases came to our emergency department because of acute abdominal pain lasting for 12 hours. He described the pain started gradually and localized at hypogastric area of abdomen. The character of pain was dullness and intermittently cramping without associated vomiting or diarrhea. Physical examination revealed localized tenderness mainly at the left lower quadrant(LLQ) and mid-abdomen without rebound tenderness.
The location of the pain in low abdomen and LLQ tenderness made us think that he might have sigmoid colon diverticulitis or left urolithiasis. But the emergency point of care ultrasound could only see little ascites at LLQ, there were no hydronephrosis or signs of diverticulitis.
Discovering little ascites urged us to seek where the problem was. So we scanned his abdomen more thoroughly including the liver, gall bladder, kidney and gastrointestinal tract and found more ascites in the Morrison’s pouch and an intestinal target lesion at the mid abdomen. Tracing this target lesion, we saw a hyperechoic tumor measured about 5 centimeter in diameter with fatty component. Under the impression of intussusception, the subsequent abdominal computed tomography(CT) proved a transverse colo-colonic intussusception caused by a huge lipoma.
An adult intussusception is a rarely seen abdominal emergency. And because it onsets insidiously and the presenting symptoms are nonspecific, the majority of cases are diagnosed lately after it causes bowel obstruction and small bowel ileus. In our case, we performed point of care ultrasound in the emergency in the first place and made the right diagnosis before small bowel ileus happened, on the other hand, it prevented the patient suffered from more serious symptoms of bowel obstruction and subsequent intestinal ischemia and infection. Interestingly, the patient complained about low abdominal pain throughout the event but not mid-abdominal pain where the lesion was located. This could be explained by the embryologic development theory that transverse colon belongs to hindgut and causes hypogastric pain as the initial symptom. And his LLQ tenderness could be related to peritoneal irritation by ascites.
We think that understanding the pathophysiology of abdominal pain plus properly trained and skillful use of point of care ultrasound is imperative in diagnosing and treating patients with abdominal pain in the emergency department.
