Intestinal Obstruction in the Newborn Differential Diagnoses

Updated: Feb 17, 2020
  • Author: James Goodwin Glasser, MD, MA, FACS; Chief Editor: Muhammad Aslam, MD  more...
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DDx

Diagnostic Considerations

The usual context of neonatal intestinal obstruction is an infant who is not feeding normally. The answers to a few questions, including the following, will suggest the correct diagnosis:

  • Is the baby vomiting? What color is the emesis?
  • Was an orogastric tube passed; if so, how much fluid was drained from the stomach? What was its color?
  • Has the baby passed meconium and/or transitional stools?
  • Is the baby's abdomen flat or distended? Is it soft or tender? Is there a palpable mass?
  • Is the baby septic? Are there other signs of ilness: irritability, temperature instability, apnea/bradycardia episodes?
  • Is examination of the baby's perineum normal? Is the anus patent?
  • Were plain radiographs obtained? Is the gas pattern normal?

The cause of bilious emesis includes sepsis, accompanied by ileus, or necrotizing enterocolitis. However, these conditions usually occur in babies who previously had demonstrated continuity of the gastrointestinal tract.

In a baby who previously tolerated feedings, midgut volvulus must always be considered in the differential diagnosis of bilious vomiting.

Babies with distal small bowel obstruction present with abdominal distention, delayed passage of meconium, and absent transitional stools (meconium mixed digested milk). Plain radiographs are usually diagnostic, demonstrating multiple dilated loops of small bowel and no air in the colon. A Gastrografin (diatrizoate) enema is diagnostic; it may also be therapeutic if the baby has meconium ileus or meconium plug syndrome.

Associated conditions

Conditions that may be associated with neonatal intestinal obstruction include the following:

  • Infants with gastroschisis may have intestinal atresia.
  • Malrotation is associated with abdominal wall defects and congenital diaphragmatic hernia.
  • Tracheoesophageal fistulas are typically associated with esophageal atresia, but isolated fistulas (H type) also occur.
  • A Meckel diverticulum or pancreatic rest (ectopic pancreatic tissue) may serve as a lead point in intussusception.
  • Occasionally, the omphalomesenteric duct forms a band between the ileum and the umbilcus that may entrap a loop of intestine.
  • Short bowel syndrome (intestinal failure) may be associated with gastroschisis, intestinal atresia, and necrotizing enterocolitis.
  • The massively dilated ascending colon should be resected, leaving a small cuff of cecum that is fashioned into an ostomy. Later, the ostomy may be anastomosed to the distal colon. See the following image.
  • Intestinal obstruction in the newborn. Colonic atr Intestinal obstruction in the newborn. Colonic atresia. The hugely dilated colon will never function satisfactorily; therefore, it is resected, leaving a cuff of cecum to preserve the ileocecal valve.

 

Intestinal perforation may be associated with the following:

  • Antenatally: Meconium peritonitis is meconium ileus with a perforation leading to extrusion of meconium into the peritoneal cavity. Usually, there are dense adhesions that make identification of the proximal and distal ends of the intestine difficult.
  • Postnatally: In micro preemies (< 800 g [1 lb, 12 oz] [20] ) with intestinal perforation, the perforated segment may have localized (aneurysmal) dilatation proximal to bowel whose caliber is tiny and whose lumen is filled (obstructed) with inspissated stool (see the image below).
  • Intestinal obstruction in the newborn. Photograph Intestinal obstruction in the newborn. Photograph of neonatal intestinal perforation. Note the aneurysmal dilatation of the (perforated) intestine proximal to the obstructed (by inspissated stool) distal ileum.

 

Developmental immaturity (infants < 26 weeks' gestational age) is a consideration in babies with intestinal obstruction, such as the following:

  • Underdeveloped musculature and poor peristalsis lead to bacterial overgrowth and a setting of immunologic immaturity; this may result in necrotizing enterocolitis.
  • Small left colon syndrome is a benign condition that occurs in infants of diabetic mothers. It is self-limited and presumably developmental; it may simulate Hirschsprung disease.

Sample diagnostic algorithm

An algorithm for the diagnosis of neonatal intestinal obstruction is depicted in the image below.

Intestinal obstruction in the newborn. This diagra Intestinal obstruction in the newborn. This diagram is a sample algorithm for the diagnosis of neonatal intestinal obstruction.