Gastrointestinal lipomatosis; A Rare Cause of Adult Jejunal Intussusception

Clinical History

A 44-year-old female presented with colicky upper abdominal pain and multiple episodes of bilious vomiting. Her bowels had not opened for five days. We were concerned about a small bowel obstruction and she had an abdominal x-ray which revealed air/fluid levels involving the gastric region.

Imaging Findings

The CT abdomen shows a rare case of gastrointestinal lipomatosis which caused jejunal intussusception (fig1-3). This was confirmed on histology.
Figure 1 shows an axial section of abdomen CT showing extensive lipomatous infiltration of the stomach wall (top left arrow). There is extensive lipomatous infiltration of the proximal duodenum (bottom left arrow), distal duodenum (bottom middle arrow) and proximal jejunum (bottom right arrow).
Figure 2 demonstrates Intussusception noted at the proximal jejunum (arrow) where one can note two concentric hyperdense rings, formed by the inner bowel and the folded edge of the outer bowel (target sign). Distally one can begin to notice the lipomatous infiltration and collapsing of the bowel.
The key finding to note in figure 3 is the collapse of bowel distal to the intussusception at the proximal jejunum (arrow).

Discussion

Gastrointestinal lipomatosis is a rare condition involving diffuse lipomatous infiltration of the gastrointestinal submucosa [1]. The aetiology still remains to be solved but possible postulations include congenital causes, defects in fat metabolism and embryonic displacement of adipose tissue [2, 3]. There is no gender or genetic disposition and the disease presents most often in the 40’s [3]. There are many cases in the literature of solitary or isolated gastrointestinal lipomas which are the second most common benign tumours of the gastrointestinal tract affecting approximately 1.5-3% of the general population [4]. Gastrointestinal lipomatosis is most often diagnosed on CT or MRI and confirmed with histology [5]. On CT, lipomas most often appear as spherical masses with well-defined margins and absorption densities of 40-120 Hounsfield units (HU), which is characteristic of fatty composition [2]. On MRI one sees high signal on T1 and T2 Fast Spin Echo (FSE) and saturation on fat saturated sequence, which has 100 percent sensitivity and specificity [5].
Adult intussusception is also extremely rare, affecting 2 to 3 per every 1 million people per annum and differs from paediatric intussusception in its aetiology and treatment, as well as presentation [6]. It most often presents as vague colicky abdominal pain (71%), nausea and vomiting (68%), partial obstruction (48%) or a palpable mass [6]. CT abdomen has a sensitivity of 80% for detecting intussusception in adults [6]. On the CT abdomen, the target sign is the most characteristic sign. Here we see the layers of bowels duplicated to create concentric rings from the telescoping of one bowel segment into another, which is seen when imaged at right angles to the lumen, or a sausage-like mass when imaged longitudinally [2]. Intravenous contrast, if used, can be seen to be trapped between the layers of bowel.
This patient had a jejunal-jejunal bypass proximal to the thickened area of jejunum. Following the operation, she was started on a liquid diet and her symptoms settled.
In conclusion, this case highlights the importance CT abdomen in the acute abdomen and is the best imaging modality to diagnose and assess the characteristics and extensiveness of gastrointestinal lipomatosis.
Conservative management is generally advised in asymptomatic patients with gastrointestinal lipomatosis.
Small bowel resection is the preferred method to treat acute intussusception in adults. However, in a case of acute intussusception secondary to extensive gastrointestinal lipomatosis, one must consider other surgical options such a jejunal-jejunal bypass, as in this case.

Differential Diagnosis List

Final Diagnosis

Adult Jejunal Intussusception secondary to Gastrointestinal lipomatosis

URL:	https://www.eurorad.org/case/14268
DOI:	10.1594/EURORAD/CASE.14268
ISSN:	1563-4086