Which two syndromes show elevated unconjugated bilirubin with normal direct bilirubin?

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When unconjugated bilirubin is elevated but direct (conjugated) bilirubin is normal, the issue lies with the liver’s ability to conjugate bilirubin rather than with excretion. Gilbert syndrome is a mild decrease in UDP-glucuronosyltransferase activity, causing slight, intermittent increases in unconjugated bilirubin with normal direct bilirubin. Crigler-Najjar syndrome, especially type I (and to a lesser extent type II), involves a severe deficiency of the same enzyme, leading to much higher levels of unconjugated bilirubin while direct bilirubin stays normal. Since both conditions raise unconjugated bilirubin without increasing direct bilirubin, they fit this pattern. In contrast, the other syndromes listed primarily involve elevated direct bilirubin due to issues with bile excretion or conjugation pathways seen in hepatocellular or transport defects, so they don’t match the described pattern.