Icterus neonatorum is characterized by an increased free or unconjugated bilirubin in the blood and increased urobilinogen in the feces and urine. So in case of icterus neonatorum, bilirubin is absent in the urine.

The cases of excretion of bilirubin in the urine derived from increased conjugated bilirubin in the blood are as followings:

* Hepatic (Hepatocellular) jaundice: Hepatitis (acute, chronic, viral and induced from drugs),

Cirrhosis, Genetic defects, Liver congestion.

* Obstructive (Posthepatic) jaundice : Carcinoma, Calculi formation, Fibrosis.