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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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The metabolic derangement in congenital pyloric stenosis is –
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The correct answer 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.