FREQUENCY OF DETECTION OF LPS O-ANTIGENS OF DIFFERENT CAUSATIVE AGENTS IN PATIENTS WITH ACUTE DIARRHEAL DISEASES

The aim is to determine the frequency and dynamics of detection of specific lipopolysaccharide (LPS) O-antigens LPS/O-antigens of causative agents in hospitalized diarrhea patients. Materials and methods. A total of 146 hospitalized diarrhea patients were examined with the use of an immunological method of the reaction of coagglutination (RCA) for the presence of LPS O-antigens of Shigella, Salmonella, Yersinia and Campylobacter in feces as markers of major intestinal infections pathogens. The control group was consisted of 40 blood donors. Results. In acute diarrhea patients there was detected the predominance of Yersinia and Salmonella LPS O-antigens over Shigella and Campylobacter; the high frequency of intestinal bacterial mixt-infection in total (68%), as well as elevated rate incidence of Shigella, Salmonella, Campylobacter, Yersinia antigens in mixt-infections in comparison with those in monoinfections (24%). The total O-antigen "load" in patients with mixt-infection was 3 times higher than in patients with monoinfections; with the increasing of LPS/O-antigen "load" the rate of Salmonella inoculation declines. Conclusion. Under the same severity of the clinical course of the disease, the decline of Salmonella inoculation rate in cases of high antigenic "load" may indicate to the presence of the phenomenon of summation of toxic effects of LPS O-antigens when the concentration of each pathogen in the feces is insufficient (for inoculation) for bacteriological examination.