This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Liver & Biliary Tract, Subject name: Pathology
Absent urobilinogen in urine with icterus indicates? 
Select and explain. 
A. Perihepatic obstruction, B. Hemolysis, C. Hepatitis, D. Liver failure
A: Perihepatic obstruction
Answer: A: Perihepatic obstruction 
Explanation: Ans. (a) Perihepatic obstruction(Ref: Robbins 9th/830-840; Harrisons 18th/chapter 42)ConditionSerum BilirubinUrine UrobilinogenUrine BilirubinFecal UrobilinogenNormalDirect 0.1-0.4 mg/dlIndirect 0.2-0.7 mg/dl0.4 mg/24 hAbsent40-280 mg/24hHemolytic anemia|IndirectIncreasedAbsentIncreasedHepatitis|Direct and indirectDecreased if micro obstruction is presentPresent if micro obstruction occursDecreasedObstructive jaundice| DirectAbsentPresentTrace to absent