What is the most appropriate next step for a newborn with abdominal distention, tenderness upon palpation, absent bowel sounds, and no meconium passage for 48 hours?

Most Appropriate Next Step for Newborn with Suspected Intestinal Obstruction

Refer immediately to pediatric surgery before obtaining any diagnostic imaging studies. 1

Critical Clinical Context

This newborn presents with peritoneal signs (abdominal tenderness and absent bowel sounds) combined with delayed meconium passage beyond 48 hours and abdominal distention—a constellation indicating potential bowel compromise requiring urgent surgical evaluation. 1

Why Immediate Surgical Referral Takes Priority

• The American College of Radiology explicitly recommends immediate pediatric surgical consultation for newborns with suspected intestinal obstruction, as the clinical presentation may indicate a surgical emergency such as intestinal atresia, malrotation with midgut volvulus, or Hirschsprung disease. 1

• The combination of absent bowel sounds with abdominal tenderness suggests peritonitis or bowel compromise, mandating immediate surgical evaluation before any diagnostic imaging. 1 This is a critical pitfall to avoid—never delay surgical consultation for imaging studies in a neonate with peritoneal signs, as this can lead to significant morbidity and mortality. 1

• Midgut volvulus requires urgent surgery and can present identically to this case, with 20% of neonates with bilious vomiting in the first 72 hours having midgut volvulus requiring urgent surgery. 1

Why Not Barium Enema First?

While contrast enema is the diagnostic imaging procedure of choice for suspected distal obstruction and can differentiate between functional abnormalities (meconium plug), pathologies requiring surgery (ileal atresia), therapeutic enema (meconium ileus), or rectal biopsy (Hirschsprung disease), 2 this imaging should only be performed after surgical consultation and stabilization, not as the initial step in a neonate with peritoneal signs. 1

Why Not Rectal Suction Biopsy First?

Rectal suction biopsy is indicated for diagnosing Hirschsprung disease, which is indeed a consideration given the delayed meconium passage. 2 However, the presence of peritoneal signs (tenderness, absent bowel sounds) indicates potential bowel compromise that requires immediate surgical assessment before proceeding with diagnostic procedures. 1 Hirschsprung disease can be life-threatening, with enterocolitis being a major cause of mortality, 3 but the acute presentation with peritoneal signs necessitates surgical evaluation first.

The Proper Diagnostic Algorithm After Surgical Consultation

Once the surgical team is involved and the patient is stabilized:

1. Plain abdominal radiographs should be obtained first to demonstrate dilated bowel loops, air-fluid levels, and presence or absence of distal gas. 1, 4

2. For suspected distal obstruction (as suggested by delayed meconium passage), contrast enema is then the diagnostic imaging procedure of choice to demonstrate microcolon in cases of distal atresia or meconium plug syndrome. 2, 4

3. Rectal suction biopsy may be performed if Hirschsprung disease remains the leading diagnosis after initial imaging and surgical assessment. 2

Common Pitfalls

• Never prioritize imaging over surgical consultation when peritoneal signs are present. 1 The mortality rate for Hirschsprung disease ranges from 1-10%, with enterocolitis being a major cause of death, 3 and delayed recognition of surgical emergencies significantly increases morbidity and mortality.

• Delayed meconium passage beyond 48 hours with abdominal distention is typical for distal bowel obstruction, which may require urgent surgical intervention. 1 Congenital malformations account for 44.6% of abdominal distention cases in premature newborns and 61.8% in full-term newborns. 5