A 55-year-old female was referred to gastroenterology service with severe and intermittent epigastric abdominal pain of 2 weeks duration. She had unintentional weight loss of 15 lbs. The pain was not associated with food intake. She had no prior abdominal surgeries. Her medical history was significant for arterial hypertension and diabetes mellitus. Physical examination revealed normal vital signs and epigastric tenderness with no palpable mass.
A complete blood count and chemistry panel were normal. An upper endoscopy and colonoscopy revealed no apparent cause of her symptoms but were remarkable for mild gastritis, diverticulosis, and small hemorrhoids. A contrastenhanced CT scan of the abdomen and pelvis showed small bowel intussusception in the right lower quadrant in mid-ileum as shown in Figure 1. For better visualization of small bowel, CT enterography was done (Figure 2) which confirmed the intussusception. An anterograde single balloon enteroscopy was unsuccessful in reaching the site of the intussusception. Surgical resection was arranged.
- What are the clinical manifestations of small bowel intussusception in adults?
- What are the causes of small bowel intussusception?
- What are the gastrointestinal manifestations of lipomas?
- What is the radiological diagnosis?
What are the Clinical Manifestations of Small Bowel Intussusception in Adults?
Intussusception is the telescoping of a proximal segment of the intestine into an adjacent distal segment. In a retrospective study,1 abdominal pain was the most frequently reported symptom (79%). The mean duration of acute pain was 4 hours, and 80% described an intermittent and cramping pain. Other described symptoms include vomiting and diarrhea. Bloody stool and a palpable mass are frequently seen in the pediatric population, however very uncommon in adults.
What are the Causes of Small Bowel Intussusception?
According to a recent meta-analysis,2 the common causes of intussusception in adults include benign tumors, followed by malignant tumors and idiopathic causes. The most common malignancies in enteric intussusception were metastatic carcinoma, metastatic lymphoma, and gastrointestinal stromal tumor (GIST). Benign tumors that can cause enteric intussusception include hamartoma, hemangioma, polyp (inflammatory, Peutz-Jegher), lipoma, and neurofibroma. These small bowel tumors typically result in lead-point for intussusception as shown in our case.
Non-lead point intussusception has been associated with celiac disease and Crohn’s disease. Inflammation with wall thickening and decreased or dysrhythmic small-bowel motility have been the suggested underlying mechanisms of intussusception.3,4
What are the Gastrointestinal Manifestations of Lipomas?
Lipomas are submucosal tumors that can grow in any part of the gastrointestinal tract and up to 20-25%5 are found in the small bowel. Most commonly lipomas are asymptomatic and found incidentally during endoscopic procedures. When symptomatic, they may have pseudopedicle that leads to intussusception. At times, they can ulcerate and cause anemia due to microscopic blood loss.
What is the Radiological Diagnosis?
The imaging modalities to assess intussusception include CT scan, ultrasound, and barium enema. The accuracy of the CT scan is varied widely, and has been reported to be 58-100%6 and is the preferred initial test of choice. Classic findings on CT scan include the target, bulls-eye, or sausageshaped lesions. When compared to a regular CT scan, CT enterography uses thinner sections and a large amount of low-density enteric contrast. CT enterography better depicts the small bowel wall and lumen making it a superior tool to assess small bowel neoplasms with a sensitivity of 84% and specificity of 96.9%.7
In our case, the CT scan of the abdomen showed small bowel intussusception involving a 12 cm segment within the right abdomen, with the characteristic sausage-shaped appearance (Figure 1). The CT enterography showed small bowel intussusception in the mid ileum and the lead point was a lipoma which measured 23 x 29 x 16 mm (Figure 2). The small bowel lipoma was not evident on the contrast-enhanced CT scan of the abdomen and single balloon enteroscopy.
- Cochran AA, Higgins GL, 3rd, Strout TD. Intussusception in traditional pediatric, nontraditional pediatric, and adult patients. Am J Emerg Med. 2011;29(5):523-527.
- Hong KD, Kim J, Ji W, Wexner SD. Adult intussusception: a systematic review and meta-analysis. Tech Coloproctol. 2019;23(4):315-324.
- Gonda TA, Khan SU, Cheng J, Lewis SK, Rubin M, Green PH. Association of intussusception and celiac disease in adults. Dig Dis Sci. 2010;55(10):2899-2903.
- Lopez-Tomassetti Fernandez EM, Lorenzo Rocha N, Arteaga Gonzalez I, Carrillo Pallares A. Ileoileal intussusception as initial manifestation of Crohn’s disease. Mcgill J Med. 2006;9(1):34-37.
- Thompson WM. Imaging and findings of lipomas of the gastrointestinal tract. AJR Am J Roentgenol. 2005;184(4):1163-1171.
- Marsicovetere P, Ivatury SJ, White B, Holubar SD. Intestinal Intussusception: Etiology, Diagnosis, and Treatment. Clin Colon Rectal Surg. 2017;30(1):30-39.
- Ilangovan R, Burling D, George A, Gupta A, Marshall M, Taylor SA. CT enterography: review of technique and practical tips. Br J Radiol. 2012;85(1015):876-886.