Pyloric Stenosis

The pylorus (from the Greek word for "gate") is the muscular opening from the stomach into the first part of the small intestine known as the duodenum. Pyloric stenosis or pylorostenosis occurs when this muscle becomes enlarged (hypertrophy) and spasms when the stomach empties, narrowing the opening (stenosis). Violent, non-bilious, projectile vomiting is a symptom of this illness. Hypertrophic pyloric stenosis is more common in infants than in older children and is thus sometimes referred to as infantile hypertrophic pyloric stenosis. Typically, a doctor may notice the enlarged pylorus as an olive-shaped bulge in the upper right quadrant of an infant's belly. It is not known whether pyloric stenosis is caused by a true-congenital anatomic constriction or simply by a functional hypertrophy of the pyloric sphincter muscle. Male infants are more likely to experience symptoms during the first two to six weeks of life.

Adults are just as vulnerable to developing pyloric stenosis as children are, with the narrowing of the pylorus generally being the result of scarring from persistent peptic ulcers. This illness is distinct from its infantile counterpart.

Causes:

Some hereditary and some environmental factors have been linked to pyloric stenosis. Firstborns are more susceptible, and boys are four times more likely to be affected. Infantile pyloric stenosis can be inherited in an extremely rare autosomal dominant pattern.

The Symptoms:

Infants with this illness typically appear with increasing vomiting at any point in the first weeks or months of life. The vomiting is more forceful than the typical spittiness (gastroesophageal reflux) found at this age, leading to the terms "non-bilious" and "projectile vomiting." While some newborns exhibit difficulties eating and subsequent weight loss, others show typical weight gain. Babies suffering from dehydration may scream without shedding tears and have less wet or soiled diapers than usual because they may go without peeing for several hours or even days. A Baby's inability to feed might also manifest as constant hunger, burping, and colic.

Diagnosis:

Medical imaging examinations, such as x-rays, may be used to confirm the results of a thorough history and physical examination and arrive at a diagnosis. Young infants who are vomiting excessively should be evaluated for pyloric stenosis. In certain cases, a mass in the epigastrium can be felt by palpating the abdomen during a physical examination. An enlarged pylorus, sometimes known as an "olive," may become visible in certain infants when they begin taking formula. Sometimes, when the stomach is straining to drive its contents out of a constricted pyloric outlet, peristaltic waves can be felt or seen (video on NEJM).

Ultrasound, when available, is used to detect or confirm pyloric stenosis by displaying the enlarged pylorus. When a baby is less than 30 days old, doctors start to worry about abnormalities such as a muscle wall thickness of 3 mm or a pyloric channel length of 14 mm.

A diagnostic "string sign" or "railroad track sign" can be seen in an upper GI series (x-rays obtained after the infant consumes a particular contrast agent), notwithstanding the series' limited use. In either case, aberrant findings are identified according to predetermined measurement criteria. A bloated stomach, like the one depicted above, can be seen on plain abdominal x-rays.

Although upper gastrointestinal endoscopy would reveal pyloric blockage, doctors would have trouble telling the difference between hypertrophic pyloric stenosis and pylorospasm based only on the findings of the procedure.

Loss of stomach acid(which contains hydrochloric acid) from chronic vomiting causes a decrease in blood potassium and chloride levels, an elevation in blood pH, and a rise in blood bicarbonate. The pH imbalance will be corrected by exchanging external potassium for intracellular hydrogen ions. These characteristics are present in all cases of acute vomiting.

Treatment:

Treatment for infantile pyloric stenosis often entails surgery; only the mildest instances may be handled medically.

Pyloric stenosis is dangerous not because of the condition itself, but because of the side effects, such as dehydration and electrolyte disruption. Therefore, early stabilization requires IV fluids to treat the infant's dehydration and the unusually high blood pH found in conjunction with low chloride levels. In most cases, this may be done in as little as 24 hours.

In certain cases, atropine taken directly or taken orally might relieve the symptoms of pyloric stenosis. While the success rate is much higher (85-89%) than that of pyloromyotomy (100%), this treatment option necessitates a longer hospital stay, competent nursing care, and close monitoring. It might be used as an alternative to surgery for kids who cannot undergo anesthetic or whose parents choose against the procedure.