Hunterian Lecture. The ontogeny of the peptide innervation of the human pylorus with special reference to understanding the aetiology and pathogenesis of infantile hypertrophic pyloric stenosis.

Infantile hypertrophic pyloric stenosis is the most common cause for urgent abdominal surgery in infancy. The aetiology of the condition is unknown. The ontogeny of the innervation and structure of the normal infant pylorus is unknown. A variety of differing histological features have been attributed to this condition and a number of animal models have been described. The histological changes in the human condition and those in the animal models have not been quantified and statistically verified. Thus, precise comparisons cannot be made. Immunohistochemistry was the principal technique employed in this study. Using this technique, the ontogeny and structure of the normal infant pylorus have been documented. The morphological and immunohistochemical changes underlying infantile hypertrophic pyloric stenosis have been quantified for the first time and compared with the quantified changes in natural and experimental animal models of this condition.