Diagnosis and treatment of primary hypertrophic pyloric stenosis (HPS) in older children

Hypertrophic pyloric stenosis (HPS) is the most important cause of non-bilious vomiting during infancy and it is usually idiopathic. It is very rare in older children and adolescents, in which gastric outlet obstruction (GOO) is more typically secondary to other conditions. Gastrointestinal malformation are frequently associated with Down syndrome and some of them (especially duodenal abnormalities) can be detected quite late. In infants the standard treatment of HPS is represented by a Ramstedt pyloromyotomy, while in adults a distal gastric resection is more indicated and it is usually associated to a Billroth I or II reconstruction.