Conjugated bilirubinemia vs UNconjugated bilirubinemia

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docjohn101

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How to tell the difference in terms of lab values?

I have seen questions, unless I was mistaken, where Total and Direct bilirubin were high, and the answer was unconjugated bilirubinemia...can someone please how to tell the difference b/w these?

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Total - Direct = indirect (unconjugated)


...

If there is a big gap between direct and total then the indirect is taking extra room = problem
 
Exactly what MrBig said.

To expand a bit more, bilirubin should be about 1 mg/dl indirect and 0 direct. Conditions increasing indirect are typically hemolytic (G6PD deficiency episode, sickle cell crisis, Rh disease of newborn), as well as Crigler-Najjar (UDP-glucuronyl transferase defective/absent, severe and rare), Gilbert (lessened effectiveness of UDP-glucuronyl transferase, benign and common), low level of conjugation enzymes in newborn (at birth, all the HgF cells have to be destroyed and switched to HgA to respond to 2,3-BPG, which may overpower developing conjugation system and cause physiological jaundice +/- kernicterus), and liver damage.
Conditions increasing direct include: bile duct obstruction (light-color stools), Dubin-Johnson (black pigmentation in liver), Rotor syndrome, and liver damage.
Thus, liver damage (cirrhosis, Wilson's, hepatitis, etc.) gives rise to both direct and direct due to variable conjugation and transport into bile duct. It's possible that the question you had presented these values, though I doubt the answer would be "unconjugated hyperbilirubinemia."
 
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