Intestinal Anomalies

Summary

Introduction

• Intestinal atresia is the most common cause of obstruction in the neonatal period.
• Incidence is approximately 1 in 10,000 births (male predominance).
• Etiology is unknown but thought to occur during weeks 8-10 of development.
• This condition is associated with Down syndrome (20-30% of Down syndrome cases), and other birth anomalies.
• Intestinal Atresias include: Duodenal atresia, Jejunoileal atresia, and colonic atresia.

Duodenal Atresia

Introduction

• Duodenal atresia and stenosis is a congenital (mechanical) obstruction of the duodenum caused by failure of the lumen to recanalize at 8-10 weeks gestation (gastric outlet obstruction).
• Clinical features include; polyhydraminos (prenatal), distention of stomach, blind loop of duodenum (double-bubble sign), and bilious vomiting.
• This condition is associated with multiple congenital anomalies including; Down syndrome.
• Treatment is surgical correction (duodenoduodenostomy)

Presentation

• Physical examination of patients with duodenal atresia may reveal scaphoid abdomen with epigastric distention.
• Duodenal stenosis may present with emesis, weight loss, and failure to thrive.

 

Diagnosis

• Diagnosis may be suspected if prenatal ultrasound demonstrates gastric dilation with polyhydraminos.
• Abdominal X-ray shows air in the stomach, and proximal duodenum (double-bubble sign) with no distal bowel gas.

 

 

Differential diagnosis

• Pyloric stenosis.
• Small intestinal volvulus due to malrotation.
• Tracheoesophageal fistula.

 

Treatment

• Nasogastric decompression to deflate the stomach.
• Hydration, and correction of electrolytes (typically hypochloremic metabolic alkalosis).
• Duodenal atresia is surgically corrected by duodenoduodenostomy.

 

Complications

• Without treatment, this condition is fatal.
• Most frequent long term complications include blind-loop syndrome, megaduodenum with altered duodenal motility, and gastritis with duodenal-gastric reflux.

Jejunoileal Atresia

 

Pediatric Abdominal Wall Defects

Introduction

• Abdominal wall defects in pediatric patients are congenital anomalies characterized by incomplete closure or structural abnormalities of the abdominal wall, leading to herniation of abdominal contents.
• The two most common types are gastroschisis and omphalocele.
• Gastroschisis: an open defect typically to the right of the umbilicus, with exposed intestines lacking a protective membrane.
• Omphalocele: a midline defect covered by a sac, often associated with other congenital syndromes.
• These conditions are often diagnosed prenatally via ultrasound.
• These conditions can lead to life-threatening complications such as infection, bowel ischemia, and respiratory compromise.

 

 

Comparison between Gastroschisis and Omphalocele

 

 

 

Management of Gastroschisis and Omphalocele

Gastroschisis Management

1. Prenatal Care:
   • Serial ultrasounds monitor fetal growth and bowel condition.
   • Delivery is often via vaginal delivery unless obstetric complications arise.
2. Immediate Postnatal Care:
   • Protect exposed bowel with a sterile, non-adhesive wrap (e.g., saline-soaked gauze and plastic bag).
   • Nasogastric decompression and IV fluids to prevent third-space losses.
   • Broad-spectrum antibiotics to reduce infection risk.
3. Surgical Repair:
   • Primary closure if possible.
   • Staged closure (silo placement with gradual reduction) for larger defects, followed by delayed fascial closure.
4. Postoperative Care:
   • Parenteral nutrition until bowel function resumes, with gradual enteral feeds.
   • Complications include: necrotizing enterocolitis, bowel dysfunction

Omphalocele Management

1. Prenatal Care:
   • Assess for associated anomalies (e.g., cardiac, chromosomal).
   • Delivery planning depends on defect size and comorbidities, with cesarean section considered for giant omphaloceles.
2. Initial Stabilization:
   • Cover the sac with a moist, non-adherent dressing.
   • Evaluate for associated syndromes (e.g., Beckwith-Wiedemann, trisomies).
3. Surgical Approach:
   • Primary closure for small defects.
   • Staged repair (e.g., mesh reinforcement, tissue expanders) for giant omphaloceles.
4. Postoperative Care:
   • Monitor for pulmonary hypertension, feeding difficulties, and recurrent herniation.
   • Long-term follow-up for growth and developmental delays is essential.

 

Prognosis

• Gastroschisis has high survival rates (>90%) but may have long-term bowel motility issues.
• Omphalocele outcomes depend on associated anomalies, with higher mortality in syndromic cases.