loss of fluid triggers aldosterone production, so patient will have hypernatremia and hypokalemia as a result
Good fact to commit to memory: you lose bicarb in the stool (hence why diarrhea causes nonanion gap metabolic acidosis), and especially lose potassium with laxative abuse (as mentioned in the question stem). https://www.uptodate.com/contents/acid-base-and-electrolyte-abnormalities-with-diarrhea
I was between hypokalemia (due to diarrhea) and hypercalcemia/hyperuricemia (since sweat is hypotonic and would cause hyperosmotic volume contraction). I didn’t have a great way to decide between hyperCa/hyperuricemia so I figured they wanted hypoK. Is there a better rationale for why the hyper answers are incorrect?
You mostly lose HCO3- and K+ in stool.
Loss of HCO3- leads to a normal anion gap metabolic acidosis (FA2019 pg. 580 'HARDASS'), in which we also see a compensatory increase in Cl-.
I have read all the comments, but none explain why hyponatremia is wrong. There is definitely Na+ in stool....thats why sugar+salt is rehydration for peds diarrheal sickness. Low Na+ causes low EVV explaining the low BP, high HR, pallor, and dehydration. Is it correct but just not as correct as C?
Chronic diarrhoea == Vit D malabsorption = Hypocalcemia (say in crohns)
ACute diarrhoea = Hypernatremia, Hypokalemia, hyperphosphatemia
Dehydration can also cause hyperuricemia and ppt gout attack, but for young pt i think this will be irrelevant