Clinical cases of toxic hepatitis: aspects of differential diagnosis with viral hepatitis

In modern conditions of environmental problems, practicing doctors increasingly have to provide assistance to patients with hepatitis, the cause of which is not only known viral agents, but also chemical poisons. General information about toxic, primarily drug‑induced, and viral hepatitis is given. The main hepatotoxic drugs are listed. Their classification, mechanism of action, clinical symptoms, biochemical and morphological changes in various toxic liver lesions are highlighted. Information on drugs with high hepatic extraction, for which there is a high risk of overdose, is highlighted. For patients from risk groups, it is advisable to at least halve the dose of such drugs in accordance with the decrease in hepatic blood flow. Drugs with low hepatic extraction have a minimal risk of overdose, although metabolic insufficiency with long‑term administration of such drugs may cause their accumulation. Finally, drugs that are excreted by the kidneys are practically devoid of the risk of hepatotoxicity. Other professional and household toxic substances that have a direct hepatotoxic effect are discussed (carbon tetrachloride, dichlorodiphenyltrichloromethylmethane, yellow phosphorus, amanito‑ and phallotoxins of the pale toadstool, various pesticides, etc.). Clinical cases of own clinical observations of various toxic hepatitises are included. The general characteristics of viral hepatitis are given, primarily with an emphasis on their differential diagnosis with hepatotoxic lesions. The main signs of viral and toxic hepatitis are grouped in the table. For a successful differential diagnosis of toxic and viral hepatitis, it is necessary to apply a modern complex of anamnestic, clinical, biochemical, virological, instrumental and morphological examination methods as fully as possible.