Infantile Hypertrophic Pyloric Stenosis: What You Need to Know

Infantile hypertrophic pyloric stenosis (IHPS) is a condition that affects young babies, usually between two and eight weeks of age. It causes severe vomiting, dehydration and weight loss. In this blog post, we will answer some common questions about IHPS and explain how it is diagnosed and treated.

What is IHPS and what causes it?

IHPS is a condition where the muscle at the lower end of the stomach (the pylorus) becomes thickened and enlarged, blocking the passage of food into the small intestine. The exact cause of IHPS is unknown, but it may be related to genetic factors, hormonal factors or environmental factors. IHPS is more common in boys than girls, and in first-born children than later-born children.

What are the symptoms of IHPS?

The main symptom of IHPS is forceful vomiting after feeding, which may occur several times a day. The vomit is usually non-bilious (not green or yellow) and may contain blood or mucus. The baby may also show signs of dehydration, such as dry mouth, sunken eyes, decreased urine output and lethargy. The baby may lose weight or fail to gain weight as expected. The baby may also have a palpable lump in the upper abdomen (the hypertrophied pylorus) and visible peristaltic waves (waves of stomach contractions) moving from left to right.

How is IHPS diagnosed?

IHPS is usually diagnosed by a physical examination and an abdominal ultrasound. The physical examination may reveal a dehydrated baby with a distended stomach and a palpable pyloric mass. The abdominal ultrasound can confirm the presence of a thickened and elongated pylorus with a narrow opening (the pyloric channel). Other tests, such as blood tests, urine tests and X-rays, may be done to rule out other causes of vomiting and to assess the baby's electrolyte balance and hydration status.

How is IHPS treated?

IHPS is treated by surgery, called pyloromyotomy. This involves making a small incision in the abdomen and cutting through the thickened muscle of the pylorus, creating a wider opening for food to pass through. The surgery is usually done under general anesthesia and takes about 15 to 30 minutes. The baby can usually start feeding within a few hours after surgery and go home within one or two days.

What are the possible complications of IHPS?

IHPS can lead to serious complications if left untreated, such as malnutrition, electrolyte imbalance, metabolic alkalosis (a condition where the blood becomes too alkaline), bleeding ulcers, infection and shock. The surgery for IHPS is generally safe and effective, but it may have some risks, such as bleeding, infection, wound healing problems, anesthesia complications and recurrence of symptoms.

How can I prevent IHPS?

There is no known way to prevent IHPS, as the cause is not fully understood. However, some studies suggest that breastfeeding may reduce the risk of IHPS compared to formula feeding. If you notice any signs of IHPS in your baby, such as frequent vomiting, dehydration or weight loss, you should seek medical attention as soon as possible.