Intussusception

Question 1

Define intussusception.

Answer 1

Invagination of proximal bowel (intussuscepian) into distant component (intussusceptum).

Question 2

Explain the aetiology for intussusception.

Answer 2

90% idipathic.
Physiological lead point: Peyer’s patch (gastroenteritis enlarges)
Pathological lead point: malignancy, Meckl’s diverticulum, Henoch-Schonlein purpura

Question 3

Summarise the epidemiology of intussusception.

Answer 3

Most common cause of SBO in 3m-2y

Rare <3m

M > F 2:1

Question 4

What are the presenting symptoms of intussusception?

Answer 4

Triad:

Vomiting (May be bile stained depending on site)

Colicky severe pain (can become inconsolable)

Red currant jelly stool: late signs due to mucosal necrosis + sloughing

Question 5

What are the signs of intussusception?

Answer 5

Abdo distention with sausage shaped mass in RUQ
Emptiness on palpation in RLQ (Dance’s sign)

Question 6

What are appropriate investigations for intussusception?

Answer 6

1. Abdo USS: may show donut sign/ target mass (think: intUSSusception)
2. AXR (paucity of air in RUQ + large bowel, thickened wall, poorly defined liver edge, dilated small bowel loops)
3. Barium/ gastrogaffin enema if have 1 of 3 Ps: Perforation, Peritonitis, Pale complexion

Question 7

What is the management plan for intussusception?

Answer 7

EMERGENCY

If stable:

• Fluid resus
• NG tube insertion if repeatedly vomiting
• Air insufflation under radiological control (traditionally barium enema: pneumatic forces bowel to un-telescope - take x rays throughout

If unstable/ perforated:

• Surgical reduction with broad spectrum abx (clindamycin + gentamicin)
• Remove non-viable bowel

Question 8

What are complications associated with intussusception?

Answer 8

Shock

Peritonitis

Intestinal perforation

Question 9

What should be done if there is recurrent intussusception?

Answer 9

Recurrence risk 5%

Investigate for a lead point

(Meckel’s diverticulum, Polyps, Appendix)

Question 10

What is the most common site of intussusception?

Answer 10

Ileum into caecum through ileocaecal valve

Question 11

Describe the pathophysiology of intussusception

Answer 11

1. Stretching + constriction of mesentery
2. Venous return obstruction
3. Engorgement + bleeding from mucosa, fluid loss
4. Bowel perforation, peritonitis + gut necrosis

Question 12

What are Peyer’s patches?

Answer 12

Oval/ round lymphoid follicles located in lamina propria layer of mucosa + extending into submucosa of ileum.