Description
Case report
A 30-year-old woman presented with severe lower, colicky abdominal pain and difficulty in passing flatus. Clinical examination revealed suprapubic tenderness.
An abdominal CT was performed which revealed a soft-tissue mass in the pelvis demonstrating ‘a target sign’ appearance confirming the diagnosis of intussusception (figure 1). The effect of the intussusceptum within the intussuscipiens creates a layered appearance. There is loss of gas within the rectum, instead, this is replaced by a soft-tissue mass of fat density (Hounsfield units −10) (figure 2). A diagnosis of rectosigmoid intussusception was carried out based on the CT findings with a presumptive diagnosis of an intramural lipoma as the primary lead point. Surgical reduction was performed with resection of the distal sigmoid colon. Histology confirmed an intramural lipoma of the sigmoid colon.
Figure 1.
Axial images of a contrast-enhanced CT scan of the pelvis. On the left the mesentery is seen to twist as bowel begins to telescope through another loop of bowel (red arrow). On the right the typical ‘target sign’ appearance of intussusception may be appreciated (red arrow).
Figure 2.
On the left: axial slice of a contrast-enhanced CT scan through the pelvis demonstrating soft tissue of fat density (intramural lipoma) within the rectum which proved to be the lead point for the intussusception (red arrow). On the right: coronal reconstruction demonstrating the layered appearance of bowel within bowel (red arrow).
Discussion
A rare cause of abdominal pain in adults is intussusception. Telescoping of bowel causes symptoms of bowel obstruction and in infants typically presents with ‘blackcurrent jelly’ stools. Intussusception occurs more frequently in the paediatric age group, with 5% of cases occurring in adults. In children, no underlying cause is generally found, while in adults 90% will be caused by an underlying pathology.1
CT has been reported to be the most valuable tool for the diagnosis of intussusception, proving to be superior to ultrasound and contrast studies.2 In adults, intussusception is usually treated by surgical intervention. This is because of the high probability of an underlying structural lead point which may be malignant in nature.3
Learning points.
Radiological investigation is paramount in confirming the diagnosis.
Keep in mind rare conditions which may present as abdominal pain.
Intussusception in adults is more often associated with an underlying lead point.
Footnotes
Contributors: CA and EV performed the literature review and drafted the article. RG and AM performed the radiological diagnosis of the patient.
Competing interests: None.
Patient consent: Obtained.
Provenance and peer review: Not commissioned; externally peer reviewed.
References
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