THE DIAGNOSIS OF SUBCLINICAL HEPATIC-ENCEPHALOPATHY IN PATIENTS WITH CIRRHOSIS USING NEUROPSYCHOLOGICAL TESTS AND AUTOMATED ELECTROENCEPHALOGRAM ANALYSIS

Neuropsychological tests used for the assessment of subclinical hepati c encephalopathy (SHE) may overdiagnose SHE because scores are usually not corrected for age, The aim of this study was to estimate the prev alence of SHE using two easy administrable psychometric tests (Number Connection Test part A [NCT-A], Symbol Digit Test [SDT]) with age-rela ted normal values, In addition, spectral electroencephalogram (EEG) wa s used, which is the in-house electrophysiological method for quantify ing encephalopathy, One hundred and thirty-seven consecutive patients (mean age 49 years, range 17-77) with cirrhosis without any clinical s igns of encephalopathy, were screened for SHE, In addition, the Child- Pugh score and the arterial blood ammonia were determined. Patients wi th concurrent use of alcohol, benzodiazepines or anti-epileptics were excluded, Fifty percent of the patients had an abnormal NCT according to the standard recommended procedure, in contrast only 7% of the pati ents had an abnormal NCT when scores corrected for age were used, Comb ining the results of the spectral EEG and the psychometric tests corre cted for age yielded a higher prevalence of SHE (23%) than when each t est method was used alone (17% vs, 10% abnormal, respectively), Severi ty of liver disease correlated with the presence of SHE, because the p revalence of abnormal tests increased from 14% in Child-Pugh grade A t o 45% in Child-Pugh grade B or C. Age above 40 years and an elevated b lood ammonia level were significant determinants related to an abnorma l EEG, We conclude that the NCT uncorrected for age markedly overdiagn oses SHE and, therefore, should not be used as a test for the screenin g of SHE. Using a combination of spectral EEG and two psychometric tes ts with age corrected normal values a low prevalence of SHE in patient s with Child A liver cirrhosis is found. Older patients with an elevat ed arterial ammonia are more prone to develop SHE than younger patient s with an equal arterial ammonia concentration.