ABSTRACT
Infantile hypertrophic pyloric stenosis (IHPS) is the most common condition requiring surgery in the first few months of life. It is characterized by hypertrophy of the circular muscle of the pylorus, causing pyloric channel narrowing and elongation. Although earlier diagnosis, advances in fluid and electrolyte therapy, and pediatric anesthesia have reduced the mortality to practically zero, the exact etiology of pyloric stenosis is unknown. Various environmental and mechanical factors have been proposed as potential causes of IHPS. Significant correlation has been found between higher pesticide use in the families' living area and the development of IHPS. As IHPS tends to run in families, genetic factors have been implicated in its etiology. IHPS is relatively rare in babies of African, Indian, and Chinese extraction. Although the smooth muscle sphincter tone is myogenic, contraction and relaxation are under neural control via activation of excitatory and inhibitory pathways, respectively.
