What is pyloric stenosis?

Answer 1

Pyloric Stenosis (PS) is the thickening of the pylorus (the muscle band at the outlet of the stomach) which results in its narrowing: the canal between the stomach and small intestine becomes unable to pass food. Vomiting, dehydration, wasting and death are the result.

This condition can occur in adults when it is usually caused by scarring from ulcers. Such cases are decreasing in numbers due to the identification and treatment of Helicobacter pylori, the ulcer causing bacterium.

Today PS occurs most commonly in babies, when the muscle ring mysteriously thickens. In infancy, symptoms usually start between 2 and 8 weeks after birth, although they can appear at any time from birth and during the first six months. Mild cases can remain untreated but cause continuing trouble.

The symptoms include chronic and often increasingly violent projectile vomiting after feeds (more than just "sick" or regurgitating milk - it's a real gush or fountain!), poor weight gain or weight loss, and dehydration. Also likely are irregular or loss of bowel movements, stomach cramps, irritability, blood-stained vomit, lethargy and wave movements across the stomach.

Incidence The condition is more common in Caucasians and males than females. PS occurs in 2-5 boys in 1000 and about 4 times less often in girls.

Treatment The condition can be diagnosed by a Barium swallow, ultrasound, blood tests, and often physically feeling for the "pyloric olive" or swollen muscle through the infant abdominal wall.

The medical world is reluctant to suspect PS and rush to surgery when faced with a vomiting baby. Hey, all infants are sick sometimes and how many parents aren't over-anxious? Sadly, careful listening and diagnosis are often a last resort when the baby's condition has deteriorated to an obvious, perhaps critical extent. At that stage surgery after restoring blood chemistry and hydration by IV is often the only option.

The surgical treatment is usually by a simple and usually immediately effective procedure to split and spread the pyloric muscle down to the lining of the passage, and recovery takes just a few days in most cases. Open surgery is being increasingly replaced by keyhole access or a small incision around the navel, but these should only be done by a specialist surgeon. The pylorus muscle is like a donut and is split and spread to disable it. This quickly restores normal gastric function and the baby typically thrives! The cut muscle returns to normal over several weeks.

Currently the drug Atropine is once again being trialled to treat pyloric stenosis and prevent surgery. It relaxes the pyloric muscle which eventually resumes its normal size and functioning. Many pediatricians and surgeons find the medical treatment option a waste of time as the surgery is quick and effective, whilst Atropine therapy is only successful in about 80-90% of cases, is possible only for non-critical cases and usually takes several weeks of careful treatment in hospital and at home.

The causes of infant PS are still little understood but infant PS is multi-factorial. About 20% of patients have one or more relatives with the history. Being a first born male Caucasian with blood group O or B are each risk factors. Maternal stress during the last trimester seems to be one of several circumstantial risk factors and breast feeding seems to be slightly preventative. There are also biochemical indicators which are too technical to detail here.

History Apart from hernias and circumcisions pyloromyotomy is the most common surgery among newborn infants. PS has been recognized for about 300 years and a simple surgical remedy that has been available since Conrad Rammstedt's accidental discovery in 1912 started to reduce a horrendous Death Rate to virtually nil.

The Future Perhaps because it's so common in pediatric medical practice and so easily and effectively remedied, there seems to be little interest in discovering more about the causes and alternative treatments of PS in infants.

However, infant surgery and a scarred body have a long-term effect on some patients and their parents, so early diagnosis and the medical treatment option with Atropine should arguably be considered more often in non-emergency cases.

Answer 2

In pyloric stenosis, the muscular wall of the passage becomes abnormally thickened. This causes the pylorus to become too narrow, which prevents food from emptying out of the stomach in a normal fashion