Pyloric stenosis: Symptoms, causes, and treatment

Jan 16, 2024

Pyloric stenosis is a rare condition that occurs when the passage between the stomach and the small intestine narrows. It typically occurs in infants and can cause an obstruction, leading to projectile vomiting, abdominal cramps, dehydration, and hunger.

Experts estimate that pyloric stenosis affects 2–5 in every 1,000 births. They also report that it usually affects infants under 6 months of age and is less common in older children. Without treatment, pyloric stenosis may affect growth and development.

This article outlines the causes and symptoms of pyloric stenosis, along with information on diagnosis and treatment.

Pyloric stenosis is a rare condition that occurs when the pylorus, a muscular valve that sits at the bottom of the stomach, thickens. This causes the pylorus to narrow.

Typically, the pylorus opens and closes to allow food through to the small intestine during digestion. When pyloric stenosis develops, this cannot happen as it should. Food and fluids cannot get through easily, so the body cannot digest and absorb them.

Although this condition can occur anytime from birth onward, it usually develops within 2–8 weeks of age.

Babies with pyloric stenosis often have no symptoms at birth. When they do develop, symptoms can include:

A person should contact a doctor as soon as possible if a baby has any of the following signs and symptoms:

If the baby cannot keep any food or water down or shows signs of dehydration, dial 911 or the number of the nearest emergency department. Signs of dehydration in infants include:

Healthcare experts do not know what causes pyloric stenosis but have identified certain risk factors that may increase the likelihood. These include:

If an infant shows any signs or symptoms that could indicate pyloric stenosis, their caregiver should immediately contact a pediatrician. The pediatrician will perform a physical examination to check if an abdominal mass around the size of an olive is present in the child's upper abdomen.

They may also order other tests, including:

The gold standard treatment for pyloric stenosis is a surgical procedure known as Ramstedt's pyloromyotomy. This widens the space inside the pylorus, allowing food and fluids to pass through more easily.

Before the surgery, a healthcare professional will test the baby's blood to check they have healthy fluid and electrolyte levels. If they do not, the baby will receive IV fluids.

Next, a medical professional will administer general anesthesia, so the baby feels no pain. Then a pediatric surgeon will begin the surgery.

Surgeons can perform a pyloromyotomy in one of two ways: laparoscopically, which is minimally invasive, and through open surgery.

In a laparoscopic pyloromyotomy, the surgeon will make three small incisions and use a camera to see inside the abdomen. They then use small tools to cut the muscle around the pylorus. In an open pyloromyotomy, the surgeon makes a bigger incision on the right side of the stomach and cuts the pylorus.

The surgery usually takes about 30 minutes.

Around 6 hours after surgery, the infant can begin having small amounts of food. These amounts can gradually increase as the baby tolerates it.

The baby will usually go home after 1–2 days in the hospital. Healthcare professionals will monitor the baby for any postoperative complications during this period.

After going home, they will need some special care while they recover. This involves:

Without treatment, pyloric stenosis can cause the following complications:

Surgery for pyloric stenosis also involves a few potential complications, such as infection. However, the benefits vastly outweigh the risks, and most babies recover quickly with no adverse outcomes.

Speak with a doctor if a baby develops any of the following after surgery:

Here are answers to some common questions about pyloric stenosis.

No, pyloric stenosis cannot get better on its own. It requires treatment from a doctor.

According to a 2018 review, pyloric stenosis occurs very rarely in adults. Sometimes it is idiopathic, meaning the cause is unknown. At other times, it can appear alongside other medical conditions such as ulcers, gastrointestinal tumors, or postoperative adhesions.

If untreated, pyloric stenosis can cause severe complications. However, the outlook for infants who do receive the surgery is generally good. Most make an excellent recovery, and very few experience any long-term problems due to the condition.

Pyloric stenosis is a rare condition that typically affects infants below the age of 6 months. It occurs when the pylorus, the muscular valve at the bottom of the stomach, thickens.

Infants with pyloric stenosis may not appear sick at first, but as the pylorus narrows, it becomes more difficult for food and water to pass through.

Symptoms of pyloric stenosis include projectile vomiting, stomach cramps, constipation, and dehydration. If someone is concerned a child may have pyloric stenosis, they should talk with a doctor immediately. A person with pyloric stenosis needs surgery to correct the condition and improve digestive function.