elevated direct bilirubin levelsbilirubin direct levelsdirect versus indirect bilirubinelevated direct bilirubinhigh indirect bilirubin causeshigh direct bilirubin causesnormal bilirubin direct levelsdirect and indirect bilirubin levelsserum bilirubin direct highdirect bilirubin slightly elevatedhigh direct bilirubin levels in adultselevated total and direct bilirubin