Congenital pyloric stenosis causes: 1. Bilious vomiting 2. Non- bilious vomiting 3. Projectile vomiting 4. Non projectile vomiting 5. Forceful

The vomiting in pyloric stenosis may or may not be projectile, however non bilious vomiting after feed is the characteristic feature. In about 10-15% of infants vomiting may contain blood. This bleeding is due to reflux esophagitis, a common association with hyperophic pyloric stenosis. Also know: Associated anomalies occur in 6-20% of patients. These includes esophageal atresia, Hirschsprung's disease, anorectal anomalies, and intestinal malformation. Ref: Nelson 17/e, Page 1229.