Pyloric Stenosis

Pyloric stenosis is a medical condition that affects the pylorus, which is the passage between the stomach and the small intestine. It is characterized by the thickening of the muscle around the pylorus, leading to narrowing of the passage and obstruction of food flow from the stomach into the small intestine.

Causes

The exact cause of pyloric stenosis is not fully understood, but it is believed to be related to a combination of genetic and environmental factors. In infants, pyloric stenosis is often associated with the use of erythromycin, a type of antibiotic, in the first few weeks of life. Other potential risk factors include:

Symptoms

The symptoms of pyloric stenosis typically develop in infants between 3-6 weeks of age and may include:

Diagnosis

The diagnosis of pyloric stenosis is typically made based on a combination of physical examination, medical history, and diagnostic tests. These may include:

  • Ultrasound: to visualize the thickening of the pylorus muscle
  • Barium swallow study: to evaluate the flow of food through the stomach and small intestine
  • Endoscopy: to visually examine the inside of the stomach and small intestine
  • Physical examination: to check for signs of dehydration, weight loss, and abdominal tenderness

Treatment

The treatment for pyloric stenosis typically involves surgical intervention to widen the narrowed passage. The most common procedure is a pyloromyotomy, which involves making a small incision in the thickened muscle to allow food to pass through more easily.

In some cases, medical management may be attempted before surgery, using medications to help relax the pylorus muscle and improve food flow. However, this approach is typically only effective for a short period of time, and surgery is often necessary to provide long-term relief.

Complications

If left untreated, pyloric stenosis can lead to serious complications, including:

  • Dehydration and electrolyte imbalance
  • Malnutrition and weight loss
  • Gastroesophageal reflux disease (GERD)
  • Infection or perforation of the stomach or small intestine

Prognosis

The prognosis for infants with pyloric stenosis is generally excellent, with most making a full recovery after surgical treatment. However, it is essential to seek medical attention promptly if symptoms persist or worsen over time.

Frequently Asked Questions (FAQs)

What is pyloric stenosis?
Pyloric stenosis is a condition where the pylorus muscle thickens, blocking food from entering the small intestine.

What are the symptoms of pyloric stenosis?
Symptoms include vomiting, dehydration, and weight loss, typically in infants 2-8 weeks old.

What causes pyloric stenosis?
The exact cause is unknown, but it may be related to genetic and environmental factors.

How is pyloric stenosis diagnosed?
Diagnosis is typically made through physical examination, ultrasound, and upper GI series.

What is the treatment for pyloric stenosis?
Treatment usually involves surgical intervention, such as pyloromyotomy, to relieve the blockage.

Is pyloric stenosis life-threatening?
If left untreated, it can lead to severe dehydration and malnutrition, but with prompt treatment, the outcome is generally good.

Can pyloric stenosis be prevented?
There is no known way to prevent pyloric stenosis, as the cause is not fully understood.

What is the prognosis for infants with pyloric stenosis?
With surgical treatment, most infants recover fully and have a normal quality of life.

Are there any complications associated with pyloric stenosis?
Potential complications include dehydration, electrolyte imbalance, and gastric perforation, but these are rare with prompt treatment.

How common is pyloric stenosis?
Pyloric stenosis affects approximately 2-4 per 1000 live births, with a higher incidence in males.

Article last updated on: 18th October 2025.
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