Animal naming test for the assessment of minimal hepatic encephalopathy in Asian cirrhotic populations.

Background And Aim: To evaluate the diagnostic performance of simplified animal naming test (S-ANT1) for minimal hepatic encephalopathy (MHE) in patients with cirrhosis from a Chinese tertiary centre and to optimize the application strategy of S-ANT1 in clinical practice.

Methods: The Animal Naming Test 1 (ANT1) was performed in all included cirrhotic patients and healthy volunteers. S-ANT1 was calculated to adjust for age and education. Psychometric Hepatic Encephalopathy Score (PHES) was also performed in patients with cirrhosis.

Results: 88 cirrhotic patients and 34 healthy control subjects were included. Cirrhotic patients were characterized with lower S-ANT1 scores (P =  0.001). In patients with cirrhosis, score of S-ANT1 was correlated with PHES score, age, school education period, and blood ammonia (all P values <0.05). With ≤20 animals as the cut-off value, S-ANT1 could distinguish MHE and no MHE with a sensitivity of 77.5% and a specificity of 58.3%. A three-step screening strategy, with 90% as a threshold for sensitivity and specificity and two cut-off values "≤12 animals" and ">23 animals", was then formulated to rule out patients with high possibility of MHE and with high possibility of no MHE. The remaining "ruled-in" patients should be further evaluated for MHE using PHES.

Conclusions: S-ANT1 is an important screening tool for MHE in cirrhotic patients. The three-step screening strategy based on S-ANT1 and PHES is conducive to the identification of MHE in clinical practice.