[Abdominal pain syndrome: etiology, pathogenesis, diagnosis and treatment].

The following issues are overviewed in the paper: definition of abdominal pain syndrome (APS), mechanisms of its development, modern classification, variants and peculiarities of APS in different pathological conditions (chronic gastritis, ulcer disease, chronic cholecystitis, chronic pancreatitis, gastro-oesophageal reflux, etc.), diagnostic data and medical history, physical, laboratory, and instrumental studies, differential diagnosis, treatment of APS of different etiology, strategy of anesthetic drug therapy.