Explanation
•Early after birth an infant with pyloric stenosis begins to regurgitate or occasionally vomits. As obstruction of the pylorus continues, the vomiting becomes projectile. Projectile vomiting is the most common symptom of pyloric stenosis.
•The pyloric sphincter is the opening between the lower portion of the stomach and the beginning portion of the intestine, the duodenum. If hypertrophy or hyperplasia of the muscle surrounding the sphincter occurs, it is difficult for the stomach to empty, a condition called pyloric stenosis.
•Incorrect: Dehydration and an olive-like abdominal mass in the right upper quadrant may also be present.
•Incorrect: Currant jelly stools are characteristics of intussusceptions.