Intussusception

Disease Description (Causes and Symptoms)

• Definition: Intussusception is a condition in which one segment of the intestine telescopes into an adjacent segment, causing intestinal obstruction and impaired blood flow. In children, the most common form is the ileum (the end of the small intestine) telescoping into the colon near the cecum.
• Main pathophysiology: If the telescoped intestinal segment loses its blood supply, edema, ischemia, and necrosis may occur, potentially progressing to intestinal obstruction, abdominal pain, bleeding, and shock.
• Main causes
  • Most cases (approximately 95%) have no identifiable cause (idiopathic). Enlargement of lymphoid tissue (Peyer’s patches) at the terminal ileum in children may be a triggering factor.
  • Approximately 5% are caused by structural lesions (Meckel diverticulum, cystic duplication of the intestine, polyps, lymphoma, hematoma, etc.).
  • Age at onset: Approximately 80% occur between 6 months and 2 years of age. It occurs slightly more often in boys (3:2). A seasonal increase (during seasonal transitions) has been reported.
• Main symptoms
  • Intermittent, severe abdominal pain (drawing up the legs and twisting the body), vomiting (food contents initially, followed by bilious vomiting), and mucous bloody stool (sticky bloody stool, “jelly-like” bloody stool) — these commonly appear within 12 hours of onset.
  • Abdominal mass (sausage-shaped mass in the right upper abdomen), abdominal distension, tenderness, signs of dehydration, fever, and shock; on rectal examination, the intussuscepted intestine may be palpable or may protrude through the anus.
• Diagnostic summary
  • Plain abdominal X-ray: Evaluation of the distribution of intestinal gas (including signs of obstruction).
  • Abdominal ultrasonography: Characteristic findings such as a target (doughnut) sign or a calf-tongue-like shape — noninvasive and highly accurate for diagnosis.
  • Air or barium enema (contrast enema): Used for both diagnosis and treatment (performed under fluoroscopic guidance).

Treatment Methods

• Emergency principles: Immediate emergency department/pediatric surgery evaluation is required when intussusception is suspected. In cases of dehydration or shock, emergency treatment is required (establishing intravenous access, fluid replacement, and hemodynamic stabilization if necessary).
• Nonoperative reduction (first-line treatment)
  • Air enema or contrast-agent enema (barium or water-soluble contrast agent): Performed under fluoroscopic (or ultrasonographic) guidance to unfold the intussusception using pressure within the intestine. The success rate is approximately 80–95% (varies depending on the case and conditions; approximately 90% in the cited material).
  • Conditions for performance: There must be no suspected intestinal perforation, peritonitis, or severe intestinal necrosis, and no suspected structural lesion.
  • Complications: Intestinal perforation may occur rarely, causing acute peritonitis.
  • Recurrence: Recurrence is possible in approximately 10% of cases after reduction. Repeat reduction may be attempted in cases of recurrence (the strategy varies depending on age and the presence of a structural cause).
• Surgical treatment
  • When possible, manual reduction (pushing the intestine out by hand) is performed, and if the condition is good, the procedure is completed without resection.
  • Intestinal resection and removal of the lesion are required in cases of intestinal necrosis or perforation, failed manual reduction, suspected structural lesions, or repeated recurrence in children aged 2 years or older.
  • Recovery and observation after surgery, with pathological examination if necessary (to identify a structural cause).
• Conservative and supportive treatment
  • Fasting, intravenous fluids, electrolyte correction, pain management, and antibiotics if necessary (when perforation or peritonitis is suspected).
  • At least 24 hours of observation after reduction is recommended (to monitor for recurrence and complications).
• Precautions, risk of complications, and self-care
  • Because this is an emergency condition, prompt medical attention is essential when symptoms occur.
  • Complications: Intestinal necrosis, perforation, peritonitis, sepsis, and shock; short bowel syndrome may occur after extensive resection.
  • Caregivers should be educated about the possibility of recurrence after reduction (return to the hospital immediately if abdominal pain, vomiting, or bloody stool occurs again).
  • Follow instructions regarding postoperative wound care, fluid and nutritional supplementation, and activity restrictions during the recovery period.

Outpatient Visit Checklist (Including Sample Questions)

• Items to bring/information to provide
  • Time of symptom onset and progression (characteristics, intervals, and duration of abdominal pain), vomiting (number of episodes and appearance), and stool (presence of blood or mucus; bring photographs if possible).
  • Previous imaging studies and test results (bring abdominal X-ray or ultrasound images or reports if available).
  • Current medications, history of allergies, previous surgeries, and underlying diseases (especially blood disorders, lymphoma, etc.).
  • The child’s recent vaccination history (if requested during the visit).
  • Notes on signs of dehydration (decreased urine output, dry lips, lethargy, etc.).
• Examples of questions that may be asked during the outpatient visit
  • When did the symptoms begin? Is the pain intermittent or continuous?
  • What is the color of the vomit (is it bilious), and how many times has vomiting occurred?
  • Have you seen blood or mucus in the stool? Do you have a photograph?
  • Has the patient experienced similar symptoms before?

Examples of General Questions to Ask the Doctor

• What is the most likely cause in this condition (idiopathic versus a structural lesion)?
• What are the success rate and risks, such as perforation, of reduction (air/contrast enema)?
• If surgery is needed, what procedure is expected, and what are the possible complications and recovery period?
• What is the risk of recurrence after resolution, and how should recurrence be managed?
• Are there any special dietary or activity instructions to follow at home?

Examples of Disease-Specific Questions

• In this patient’s (or our child’s) case, is reduction likely to be sufficient, or should a structural cause (such as a polyp or diverticulum) be suspected? Are additional tests needed?
• If recurrence occurs after reduction, how many times can nonoperative reduction be attempted again, and what are the criteria for recommending surgery based on age (e.g., 2 years or older) or the number of recurrences?