The metabolic derangement in congenital pyloric stenosis is –

Clinical manifestations of congenital hypertrophic pyloric stenosis Pyloric stenosis is usually not present at birth. Nonbullous vomiting is the initial symptoms of pyloric stenosis. The vomiting usually starts after 3 weeks of age, but symptoms may develop as early as the 1st week of life and as late as the 5 months of life. Emesis may follow each feeding, or it may be intermittent. After vomiting, the infant is hungry and wants to feed again. Due to vomiting, there is a progressive loss of→ Fluid, Hydrogen ion, Chlorides This results in hypochloremic metabolic alkalosis. Serum potassium levels are usually maintained, but there may be a total body potassium deficit. Jaundice (unconjugated bilirubin) is associated with a decreased level of glucuronyl transferase in 5% of patients.