the condition is due to enlarged pylorus sphincter muscle. occurs more in full term male white infants. seen in downs syndrome. also a hereditary component. occurs between 1 and 2 weeks or 3 and 4 months. relatively common... increased gastrin secretion in pregnant women may contribute to pyloric stenosis in their infants
pathophysiology of pyloric stenosis
the circular muscle of the pylorus is enlarge because of increased cell size. (hypertrophy) and an increase in cell number (hyperplasia). transforming growth factor-alpha plays a role in stimulating the increase in muscle mass. the mucosal lining of the pyloric opening is folded and the lumen is narrowed by the muscle. stomach muscle may also hypertrophy because of the effort to force the gastric contents through the narrowed pylorus.
well feeding infant begins to vomit for no reason. projectile vomiting and constipation, can lead to malnutrition. antispasmodic drugs to maintain nutrition until the condition reverses.