MedGen

Infantile pyloric stenosis is the most common condition requiring surgical intervention in the first year of life. It typically presents in infants 2 to 6 weeks after birth. Clinically the disorder is characterized by projectile vomiting, visible gastric peristalsis, and a palpable pyloric tumor (summary by Everett et al., 2008). Mortality was high until successful treatment by pyloromyotomy was developed by Ramstedt (1912). Genetic Heterogeneity of Infantile Hypertrophic Pyloric Stenosis Multiple susceptibility loci have been implicated in IHPS including IHPS1 on chromosome 12q, IHPS2 (610260) on chromosome 16p13-p12, IHPS3 (612017) on chromosome 11q14-q22, IHPS4 (300711) on chromosome Xq23, and IHPS5 (612525) on chromosome 16q24. [from OMIM]

Pyloric stenosis, also known as infantile hypertrophic pyloric stenosis, is an uncommon condition in infants characterized by abnormal thickening of the pylorus muscles in the stomach leading to gastric outlet obstruction. Clinically infants are well at birth. Then, at 3 to 6 weeks of age, the infants present with projectile vomiting, potentially leading to dehydration and weight loss. [from HPO]