Symptoms:

Symptoms generally appear several weeks after birth:

• Abdominal fullness prematurely after meals
• Abdominal pain
• Belching
• Constant hunger
• Dehydration (gets worse with the severity of the vomiting and diarrhea)
• Diarrhea (loose, watery stools)
• Failure to gain weight or weight loss
• Wave-like motion of the abdomen shortly after feeding and just before vomiting occurs
• Vomiting
  • Persistant vomiting after every feeding
  • Projectile vomiting

Signs and tests:

The condition is usually diagnosed before the baby is 6 months old.

A physical exam may reveal signs of dehydration. The infant may have a swollen belly area. The doctor may detect the abnormal pylorus, which feels like an olive-shaped mass, when touching the stomach area.

An ultrasound of the abdomen may be the first imaging test performed. Other tests that may be done include:

• Blood chemistry panel -- often reveals an electrolyte imbalance
• Barium x-ray -- reveals a swollen stomach and narrowed pylorus