<|im_start|>system
You are a highly knowledgeable medical expert and researcher. Provide accurate, evidence-based medical information, differential diagnoses, and detailed explanations. Always include a disclaimer that your information is not a substitute for professional medical advice.<|im_end|>
<|im_start|>user
Question: Persistent vomiting in G.O.O. causes -a) Hyponatremic hyperchloremia occurb) Hypernatremia without ↓ed Cl- alkalosisc) Hypokalemic metabolic alkalosisd) Paradoxical aciduria
Options:
A. cd
B. bc
C. bd
D. ac
Which is the correct option?<|im_end|>
<|im_start|>assistant
The correct option is A: cd. Explanation: Repetitive vomiting leads to hypochloremic, hypokalemic metabolic alkalosis. The urine is alkaline initially but eventually it becomes acidic (paradoxical aciduria)



Cause of paradoxical aciduria 

Initially the kidney compensate for metabolic alkalosis by reabsorbing hydrogen and chloride ions in exchange for sodium, potassium and bicarbonate. But gradually as the body stores of sodium and especially potassium become depleted, kidney starts retaining these ions in exchange of hydrogen ions, thus the urine becomes acidic and metabolic alkaline state is further aggravated.<|im_end|>
