Minimal hepatic encephalopathy – underestimated complication of chronic liver disease

Hepatic encephalopathy is a group of neurological and psychiatric symptoms ranging from subclinical to overt changes. It includes potentially reversible neuropsychiatric disorders, which are common complications of acute and chronic liver disease. The cognitive dysfunctions associated with hepatic encephalopathy include disorders of memory, attention, executive, verbal and visual-spatial functions. The occurrence of symptoms of severe encephalopathy in patients with cirrhosis is associated with a very high mortality rate, exceeding 50% within a year. Minimal hepatic encephalopathy (MHE) is a significant and common, but rarely recognized, complication of liver cirrhosis. It affects 30-80% of patients with liver cirrhosis, its occurrence increases the risk of overt encephalopathy, and it is associated with shorter survival time and higher mortality compared to patients with cirrhosis but without MHE. Difficulties in the diagnosis of MHE are caused by the lack of overt clinical symptoms, with simultaneous impairment of cognitive and psychomotor function. Currently MHE diagnosis is based on neuropsychological tests examining psychomotor performance, attention processes and memory, as well as neurophysiological tests assessing the function of the central and peripheral nervous system. There are no laboratory or imaging tests that allow a clear diagnosis of MHE. In therapy, in addition to the treatment of the underlying liver disease, lactulose and rifaximin are the most commonly used drugs. The aim of the study is to present the current knowledge about the symptoms and diagnosis of MHE, as well as further research directions for its diagnosis and treatment.