[Importance of control over the spread of antibiotic-resistant Shigella strains in the bacteriological diagnosis of dysentery]. / Znachenie kontrolia za rasprostraneniem antibiotikoustoichivykh shtammov shigell v bakteriologicheskoi diagnostike dizenterii.

The data on resistance of Sh. sonnei, Sh. flexneri and Sh. newcastle to antibiotics added to nutrient media in one region during a period of 12 years, i.e. from 1967 to 1978 were analysed. The analysis revealed differences in the resistance dynamics in various years. Differences in the efficiency of the nutrient medium with levomycetin for Shigella of various species were noted. It was found that the gradual loss of the medium efficiency was due to increased circulation of levomycetin-resistant Shigella, in particular Sh. newcastle and Sh. flexneri in the region during the last years. 4788 excrement samples from patients with dysentery and other intestinal diseases were inoculated onto nutrient media with various antibiotics and sensitivity of the Shigella isolates to these antibiotics was determined. Correlation between the efficiency of the media with antibiotics and the validity of the antibiotic chosen for addition to the medium was shown. The use of media with antibiotics chosen without an account for the character of the shigella antibioticogrammes resulted in decreased isolation of Shigella. Control for distribution of Shigella resistant to the antibiotics used for addition to nutrient media should be considered as an important condition for the media use increasing the quality of dysentery bacteriological diagnosis.