Intussusception

• The most common abdominal emergency of early childhood

• The telescoping of 1 part of the bowel into itself or adjacent bowel, causing abdominal pain, vomiting, and

eventually bloody stools and lethargy

• Telescoping of the bowel causes diminished venous blood flow and bowel wall edema, which can result in

ischemia and obstruction. Eventually, arterial blood flow is inhibited and infarction of the bowel wall occurs, whichresults in hemorrhage and, if untreated, possible perforation.

• Strangulation of the bowel rarely occurs in the 1st 24 hours but evolves afterward.

• Ileocolic type accounts for 80–90% of intussusceptions; ileoileal and colocolic types also occur.

• Typical triad of acute onset of colicky abdominal pain, right upper quadrant (RUQ) mass, and “currant jelly” stools,although clinical presentation can vary

• Increased incidence in children who received the Rotashield rotavirus vaccine. The currently available vaccine (Rota Teq) has not been shown to increase the risk.

EPIDEMIOLOGY

• Male/Female ratio: 3:2

• Generally occurs in 6 months to 3 years

• Peak age from 6–12 months

Incidence

1–4/1,000 live births

ETIOLOGY

• Children <3 years: Usually idiopathic or enlarged Peyer patch from viral infection

• Children 3 years or older: Often a pathologic lead point: Meckel diverticulum, hematoma from Henoch-Schönlein

purpura or bleeding diatheses, tumors (polyps, lymphoma, sarcoma, lipoma, neurofibroma), adhesions, duplication,postsurgical anastomotic sutures or staples, cystic fibrosis

Diagnosis

SIGNS AND SYMPTOMS

History

• The typical presentation is the sudden onset of severe intermittent (colicky) abdominal pain, with the child often drawing the legs up to the abdomen and crying. Can be asymptomatic between paroxysms of pain

• Lethargy out of proportion to the severity of dehydration

• Nonbilious emesis initially, becomes bilious with progressive obstruction

• “Currant-jelly” stools (sloughed mucosa, blood, and mucous) appear in 50% of cases: A sign of longer course

Physical Exam

• Lethargic with colicky pattern of abdominal pain

• Mass in the RUQ may be palpated (“RUQ sausage”)

• Absence of bowel contents in right lower quadrant (Dance sign)

• Abdominal distention

• Rectal exam: Blood-tinged mucous or currant jelly stool; occasionally the intussusception can be felt

• Peritoneal signs if intestinal perforation has occurred

TESTS

LABORATORY

CBC, electrolytes

IMAGING

• Abdominal x-ray: Not sensitive or specific. Normal in early stages, later can have absence of gas in right lower

quadrant (RLQ) and RUQ as well as RUQ soft tissue mass; with obstruction, will have air–fluid levels, paucity of distal gas

• Abdominal ultrasound: If performed by experienced radiologist, highly sensitive and specific. “Doughnut sign” with presence of several concentric rings

• Contrast enema: Diagnostic and therapeutic with reduction often achieved. Air enema preferred because less perforation risk than barium. Can miss a lead point

CLINICAL:

• Only 30% present with the classical triad of abdominal pain, palpable abdominal mass, and currant-jelly stool, so high clinical suspicion is necessary

• Clinical status of hypovolemic patients may worsen with high-osmotic contrast agents.

DIFFERENTIAL DIAGNOSIS

• Infection: Gastroenteritis, enterocolitis, parasites

• Immunologic: Henoch-Schönlein purpura

• Miscellaneous:

1. Appendicitis

2. Meckel diverticulum: May act as a lead point in the absence of bleeding

3. Incarcerated hernia

4. Hemolytic uremic syndrome

5. Obstruction: Adhesions, hernia, volvulus, stricture, bezoar, foreign body, polyp, tumor

Treatment

INITIAL STABILIZATION

• Nasogastric tube placement: Bowel decompression

• IV line placement: Correction of fluid and electrolyte losses

GENERAL MEASURES

• Prompt reduction is imperative.

• Spontaneous reduction occurs in 5%

• Obtain surgical consultation before contrast enema reduction attempt secondary to risk of perforation; failed reduction requires surgical correction.

• Absolute contraindications to reduction by enema: Peritonitis, shock, and perforation

• Relative contraindications to reduction by enema: Symptoms >24 hours, evidence of obstruction (i.e., air fluid

levels), sonographic evidence of ischemia

• Perforation during reduction occurs in 1% of cases, mostly in the transverse colon.

SURGERY

If perforation/peritonitis exists, patient is unstable, nonoperative reduction is unsuccessful, or lead point is identified, proceed to surgical reduction.

Follow-up Recommendations

Recurrence after nonoperative reduction has been reported in up to 10% of cases and usually is seen within 24 hours of the reduction.

EXPECTED COURSE/PROGNOSIS

• Timely diagnosis results in a highly favorable prognosis.

• Hydrostatic reduction by contrast enema is therapeutic in 50–90% of cases.

• Risk of recurrence is ~10% after contrast enema reduction, 1% after manual reduction, and not reported after intestinal resection; the greatest risk is in the 24–72 hours after reduction.

POSSIBLE COMPLICATIONS

• Bowel necrosis secondary to local ischemia

• GI bleeding

• Bowel perforation

• Sepsis, shock

• Q: Can my child have a recurrent intussusception?

• A: Yes, the risk is very low, probably <10% if the child has had a nonsurgical reduction or removal of the lead

point. The greatest risk is in the 1st 72 hours after reduction.

• Q: What are the common ages for presentation?

• A: 6 months to 3 years is the age range associated with the greatest risk of intussusception, but it may occur at any

age. The prevalence of pathologic conditions rises with the age of a child diagnosed with intussusception.