Pyloric stenosis

Recurrent projectile non-bilious vomiting, typically in a 3- to-6-week-old infant (usually male), but may occur in older infants.

Features may include a history of feeding intolerance with multiple formula changes.

Failure to thrive/weight loss may progress to increasing volume depletion. An olive-shaped mass may be palpable in the right upper abdomen.

Ultrasound shows pyloric channel length >17 mm and pyloric muscle thickness >4 mm.

Treatment is with intravenous fluid and electrolyte replacement, followed by pyloromyotomy (open or laparascopic).

Complications of pyloromyotomy include wound infection, gastric or duodenal mucosal perforation, or incomplete myotomy.

In infantile hypertrophic pyloric stenosis (HPS), hypertrophy of the pyloric sphincter results in narrowing of the pyloric canal. It is the most common cause of gastric outlet obstruction in the 2- to 12-week-old age group.[1]Aspelund G, Langer JC. Current management of hypertrophic pyloric stenosis. Semin Pediatr Surg. 2007 Feb;16(1):27-33. http://www.ncbi.nlm.nih.gov/pubmed/17210480?tool=bestpractice.com Pyloric stenosis leads to progressive and projectile vomiting.