This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gastrointestinal tract, Subject name: Pediatrics
In a child with acute liver failure, the most impoant abnormal serum biochemical test that indicates poor prognosis is ? 
Select and explain. 
A. Increasing transaminase, B. Increasing bilirubin, C. Increasing prothrombin time, D. Reversal of serum albumin-globulin ratio
C: Increasing prothrombin time
Answer: C: Increasing prothrombin time 
Explanation: Despite suppoive care and nursing in intensive care 40-70%children with acute liver failure die. poor prognostic markers are grade lll or more hepatic encephalopathy, prothrombin time more than 40 s , presence of sepsis and chest infection. Prothrombin time indicates coagulopathy which is a complication of acute liver failure Ref : ESSENTIAL PEDIATRICS,O.P.GHAI, PG NO:288, 7 th edition