Which characteristic is associated with obstructive jaundice?

In obstructive jaundice, there is a blockage in the biliary tract, leading to an accumulation of conjugated bilirubin in the bloodstream. This results in elevated levels of direct (conjugated) bilirubin, as it cannot be excreted into the intestines due to the obstruction.

The key characteristic of obstructive jaundice is that conjugated bilirubin rises significantly, while unconjugated bilirubin levels remain normal, because the liver is still functioning adequately to conjugate bilirubin but is hindered from excreting it. This is why the elevation of conjugated bilirubin alongside a normal unconjugated bilirubin level is indicative of obstructive jaundice.

Conversely, the assertion about the ratio of direct to total bilirubin greater than 1:2 would indicate a heightened level of direct bilirubin when compared to total bilirubin. Since total bilirubin includes both unconjugated and conjugated forms, such a ratio would indeed support the diagnosis of obstructive jaundice.

In contrast, other options such as increased urinary urobilinogen or normal urinary bilirubin levels are not consistent with obstructive jaundice. Increased urobilinogen typically indicates liver dysfunction or hemolysis, while normal urinary bilirubin suggests that