Pyloric stenosis

Pyloric Stenosis

What is pyloric stenosis?

Pyloric stenosis is a problem with a baby's stomach that causes forceful vomiting. It happens when the baby's pylorus, which connects the stomach and the small intestine, swells and thickens. This can keep food from moving into the intestine.

A baby may get pyloric stenosis anytime between birth and 3 months of age. It rarely happens in babies older than 3 months. It usually starts about 3 to 6 weeks after birth. If your baby was born early (premature), symptoms may start later.

What are the symptoms of pyloric stenosis?

A baby with pyloric stenosis may:

  • Vomit soon after a feeding.
  • Have a full, swollen upper belly after a feeding.
  • Act fussy and hungry a lot of the time.
  • Have fewer and harder stools than normal.
  • Pass less urine than normal.

Vomiting usually starts gradually. As the pylorus becomes tighter, the vomiting may become more frequent and more forceful.

As the vomiting continues, your baby may:

  • Lose weight.
  • Become dehydrated.
  • Be sleepier than normal and very fussy when awake.

How is pyloric stenosis diagnosed?

Your doctor will do a physical exam and ask about your baby's symptoms. If your baby has pyloric stenosis, the doctor may be able to feel a small lump in the upper part of the belly.

In some cases your baby may need imaging tests, such as an upper GI (gastrointestinal) series or an abdominal ultrasound. Your baby also may need blood tests to see if he or she is dehydrated.

How is pyloric stenosis treated?

Pyloric stenosis is treated with surgery to widen the opening through the pylorus between the stomach and the small intestine. Surgery rarely causes problems.

Your baby likely will be ready to go home within 2 days after surgery. Being involved in your baby's care at the hospital may help you feel more comfortable when you take your baby home. Talk with the doctor about how to feed your baby and what to expect. It's normal to feel nervous, but don't be afraid to hold and handle your baby.

How can you care for your child who has pyloric stenosis?

Your baby's care team will make sure that you have the information you need to take care of your baby at home. Follow your doctor's instructions for feeding your baby. Give any medicines as instructed. And go to any follow-up visits.

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The content above contains general health information provided by Healthwise, Incorporated, and reviewed by its medical experts. This content should not replace the advice of your healthcare provider. Not all treatments or services described are offered as services by us. For recommended treatments, please consult your healthcare provider.

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