Infantile pyloric stenosis occurs in neonates; it is acquired in the early stages of life, it was at one time thought to be a purely congenital condition.
- the child with pyloric stenosis usually presents at 3 to 4 weeks of age. In rare instances symptoms may be present at or soon after birth, but this condition rarely presents for the first time in infants over the age of 12 weeks
- the classic symptom of this condition is projectile vomiting. The vomitus does not contain bile and the child remains hungry and takes food immediately after vomiting
- the neonate vomits large quantities of curdled and unpleasant smelling milk. The vomit is forcefully ejected, justifying the adjective "projectile"
Possible features of clinical examination include:
- distended stomach and a smooth ovoid mass just below the right costal margin, which is the hypertrophied pylorus