Pyloric Stenosis | Digestive Health | Loyola Medicine

Pyloric Stenosis

Overview and Facts about Pyloric Stenosis

Pyloric stenosis is the narrowing or partial closure of the pylorus. Your pylorus is the opening between your stomach and small intestine that allows the passage of partially digested food down your gastrointestinal tract for further processing and nutrient extraction. If the pylorus is narrowed, then your digestive health is inhibited.

Pyloric stenosis is most commonly seen as a birth defect, and often occurs in babies ages zero to six months. Some cases of late-onset pyloric stenosis (pyloric stenosis occurring at seven months of age and older) have also been reported. It is the second most common reason for surgery in newborns and is more common in infant males than females. Pyloric stenosis is also referred to as infantile hypertrophic pyloric stenosis.

Symptoms and Signs of Pyloric Stenosis

The most common sign or symptom of pyloric stenosis is persistent and projectile vomiting of curdled milk, especially between meals. Dehydration and weight loss often occur as a result of persistent vomiting and nutrient depletion.

Other obvious signs and symptoms of pyloric stenosis in infants include:

  • Constipation
  • Infrequent bowel movements
  • Low energy or lethargy
  • Persistent or frequent hunger
  • Mucus-like stool
  • Frequent burping or belching
  • Abdominal cramping after feeding and just before vomiting
  • Irritability or fussiness

Causes and Risk Factors of Pyloric Stenosis

Pyloric stenosis tends to run in families with a history of the condition; however, the condition may occur in response to both genetic and/or environmental factors that continue to be characterized.

Risk factors for developing pyloric stenosis include:

  • Male gender
  • Caucasian/European ancestry
  • Heredity or family history of pyloric stenosis
  • Bottle feeding shortly after birth
  • Administration of azithromycin or erythromycin during the first six weeks of life

Tests and Diagnosis of Pyloric Stenosis

Ultrasounds and X-rays are used to visually detect the presence of pyloric stenosis in infants and children. Upper endoscopy is often used to detect it in adults. Blood tests may be conducted to measure the amount of electrolytes in the baby’s blood, as low blood electrolyte levels may indicate dehydration.  

Pyloric stenosis may also be diagnosed through a physical exam to look for signs of dehydration:

  • Swollen abdomen or belly
  • Dry diaper
  • Dry tears, skin, and mouth
  • The presence of a round mass when examining the infant’s upper belly, which indicates an abnormal pylorus

Treatment and Care for Pyloric Stenosis

Corrective surgery, or pyloromyotomy, is the primary method of treatment for pyloric stenosis in infants. Corrective surgery widens the opening between the stomach and the small intestine, or the pylorus, to provide relief and improve hydration and digestion. An endoscope may also be used to insert and inflate a balloon to widen the baby’s pylorus. Tube feeding or medication may be used as an alternative in babies who cannot undergo surgery. In adults, pyloric stenosis can be treated using both endoscopic and surgical methods.