Ammonia and endogenous benzodiazepine-like compounds in the pathogenesis of hepatic encephalopathy

Background: Ammonia and endogenous benzodiazepines (BDZs) are two of the mo st important agents among those taken into consideration in the pathogenesi s of hepatic encephalopathy (HE). Methods: Venous ammonia and endogenous BD Zs sera levels were assayed in 58 liver cirrhosis patients (34 male, 24 fem ale) free of commercial BDZs. Endogenous BDZs were measured by binding assa y after highperformance liquid chromatography purification. Ammonia was ass essed by colorimetric test. Results: Endogenous BDZs and ammonia were signi ficantly higher in Child-Pugh class C than in class B and class A (P < 0.05 ), correlating to the severity of the liver dysfunction but not with the de gree of HE. A significant difference, in fact, was noted between degree 0 ( no HE) versus III-IV of HE (P < 0.05), but not between degrees I-II versus III-IV. Regression analysis performed to find a correlation between the amm onia and BDZ levels in HE resulted negative. Conclusion: Clinical evidence is provided in cirrhotic patients that ammonia and endogenous BDZ levels do not correlate with each other in the outcome of HE.