In most patients, urobilinogen levels in the urine are less than 1 mg/dL; observed levels range from 0-8 mg/dL, according to Express Diagnostics. Urobilinogen is formed from the breakdown of bilirubin in the intestines and passed to the liver and urine.
Higher than normal levels may indicate problems with the liver, such as an overburdened liver, decreased functionality or liver cirrhosis, according to Express Diagnostics. High levels of urobilinogen may also be caused by infection, poisoning or the breakdown of excessive amounts of red blood cells. Lower than normal levels can be caused by problems with bile production or elimination.