Intussusception

An intussusception is a generally acute condition in which a section of the intestine folds into the section next to it. Cases will often involve the small intestine, however cases involving the large intestine do occur. Patients may present with abdominal pain, vomiting, abdominal bloating and blood in the stool. An Intussusception is not considered life threatening unless it has been allowed to develop, or otherwise remained untreated for some time. 

The mechanics of intussusception often result in occlusion of the bowel lumen, or a small bowel obstruction. Additionally, complications such as peritonitis and bowel perforations are also indicated¹.

Intussusception is most common in infancy and early childhood and is three times more prevalent in males³. 

Pathophysiology

In children, the cause of Intussusception is not properly understood. In adults, the cause is believed to be related to a pre-existing lead point, a condition in which part of the intestinal tissue protrudes into the lumen of the bowel.

The most common type of intussusception is when the ileum enters the cecum. It is also possible for the ileum or jejunum to prolapse onto themselves. The exact mechanism is poorly understood, but it is believed that peristaltic motions of the bowel can draw the proximal section into the distal section, however, the opposite is also possible.

A cause cannot be identified in up to 90% of cases¹.

A common misconception is that the rotavirus vaccine was the cause of many cases of intussusception. Although a link was determined in earlier versions of the vaccine, a difinitive correlation could not be established, and current versions of the vaccine has so far established no link to the condition².

Diagnostic scans

Intussusceptions are easily recognisable on CT scans as large solid “doughnut” like mass. They may also be visible on simple x-ray, but are usually only visible due to the backup of intestinal contents.

Classification

Ileocolic intussusceptions are by far the most common, followed by ileo-ileo-colic.

1. 77%    Ileocolic
2. 12%    Ileo-ileo-colic
3. 4%      Ileoleal
4. 2%      Colocolic
5. 1%      Multiple
6. 0.2%  Retrograde
7. 2.8%  Others

Video

The following video from Dr. Mellick demonstrates an acute presentation of intussusception in a young patient, and the resulting treatment of the condition.

Further Reading

Medscape | DiseaseDB | Medline

Image Credit: Wikimedia Commons