This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General surgery, Subject name: Surgery
Non-bilious vomiting seen in 
Select and explain. 
A. Meconium ileus, B. Duodenal atresia, C. Hyperophic pyloric stenosis, D. Necrotising enterocolitis
C: Hyperophic pyloric stenosis
Answer: C: Hyperophic pyloric stenosis 
Explanation: Vomiting in infancyBile-stainedIntestinal malrotation with volvulus Duodenal atresia/stenosis ( is usually just distal to the ampulla of Vater)Jejunal/ileal atresia (often isolated anomalies)Hirschsprung's diseaseAnorectal malformationsMeconium ileus (cystic fibrosis)Necrotising enterocolitisIncarcerated inguinal herniaIntussusception (often non-bilious initially)Non-bilious Infantile hyperophic pyloric stenosisGastro-oesophageal refluxFeeding difficulties (technique/volume)Non-specific marker of illness, e.g. infectionRef: Bailey and Love 27e pg: 128