Blood methanethiol in alcoholic liver disease with and without hepatic encephalopathy

Blood methanethiol and ammonia concentrations were measured in 16 healty volunteers, 52 consecutive alcoholic cirrhotics without overt hepatic encephalopathy (HE), and 42 consecutive patients with alcoholic liver disease and overt HE. The mean concentration of blood methanethiol was significantly greater than normal in the cirrhotics without overt HE, and the means of both methanethiol and ammonia were significantly greater in the patients with than in those without overt HE. Only one patient with overt HE had both normal ammonia and methanethiol blood concentrations. Twenty of the patients with HE were followed serially. The directions of change in methanethiol and ammonia were consistent with the direction of change in mental status in 85% adn 60% respectively. All of the patients who deteriorated and died had changes in blood methanethiol that correlated with the change in mental status. We conclude that blood methanethiol is a valuable adjunct to the ammonia determination in the evaluation of the patient with possible HE. It is especially helpful in following the course of a patient with hepatic encephalopathy, both as to prognosis and as an indicator of response to therapy.