Pyloric stenosis - infant

Definition

Pyloric stenosis is a narrowing of the pylorus, the opening from the stomach into the small intestine. This article describes the condition in infants.

Causes

Normally, food passes easily from the stomach into the first part of the small intestine through a valve called the pylorus. With pyloric stenosis, the muscles of the pylorus are thickened. This prevents the stomach from emptying into the small intestine.

The exact cause of the thickening is unknown. Genes may play a role, since children of parents who had pyloric stenosis are more likely to have this condition. Other risk factors include certain antibiotics, too much acid in the first part of the small intestine (duodenum), and certain diseases a baby is born with, such as diabetes.

Pyloric stenosis occurs most often in infants younger than 6 months. It is more common in boys than in girls.

Symptoms

Vomiting is the first symptom in most children:

Other symptoms appear several weeks after birth and may include:

Exams and Tests

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

A physical exam may reveal:

Ultrasound of the abdomen may be the first imaging test. Other tests that may be done include:

Treatment

Treatment for pyloric stenosis involves surgery to widen the pylorus. The surgery is called pyloromyotomy.

If putting the infant to sleep for surgery is not safe, a device called an endoscope with a tiny balloon at the end is used. The balloon is inflated to widen the pylorus.

In infants who cannot have surgery, tube feeding or medicine to relax the pylorus is tried.

Outlook (Prognosis)

Surgery usually relieves all symptoms. As soon as several hours after surgery, the infant can start small, frequent feedings.

Possible Complications

If pyloric stenosis isn't treated, a baby won't get enough nutrition and fluid, and can become underweight and dehydrated.

When to Contact a Medical Professional

Call your health care provider if your baby has symptoms of this condition.


Review Date: 9/5/2017
Reviewed By: Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

This information should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. © 1997- 2007 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.