<prompt> A 6 year old boy presenting with palpable abdominal mass in the epigastrium. The clinical diagnosis is There is no bile in vomitus ?Duodenal AtresiaCholedochal cystPyloric stenosisOesophageal Atresia  <response>: Features of pyloric stenosis : non bilious vomiting malnutrition,dehydration,hypochloremic alkalosis constipation is common peristaltic waves moving from left hypochondrium to umbilicus is visible a small mass due to pyloric thickening palpable in the transpyloric plane on the right side. Ref : ESSENTIAL PEDIATRICS,O.P.GHAI,PG NO:253,7 th edition 