Adult idiopathic hypertrophic pyloric stenosis presenting with gastroduodenal intussusception: A rare case report.

Adult idiopathic hypertrophic pyloric stenosis (AIHPS) is a rare entity first described by Cruveilhier in 1835. There are only approximately 200 cases reported in the English literature to date. Histologically, it may be mistaken for spindle cell neoplasms such as gastrointestinal stromal tumour (GIST).