Diphtheria: characteristics of the pathogen and laboratory diagnostics (lecture).

The problem of diphtheria infection remains relevant, since the circulation of toxigenic strains of Corynebacterium diphtheriae persists in the body of bacterial carriers, despite ongoing vaccination. The lecture presents modern ideas about the properties of the pathogen, its pathogenicity factors (toxin, pili, surface proteins (67-72P (or DIP0733), DIP1281, etc.) and their role in the pathogenesis of the disease.. Information about the clinical and epidemiological characteristics and modern methods of laboratory diagnostics of diphtheria is presented. The algorithm of bacteriological research and methods for determining the toxigenic properties of the pathogen are described. The basics of diphtheria vaccination as the only effective means of preventing mass outbreaks of this disease are considered in the framework of the proposed lecture. Knowledge of the peculiarities of the circulation of strains of Corynebacterium diphtheria in modern conditions, pathogenetic and clinical-epidemiological features of diphtheria, as well as modern methods of laboratory diagnostics is important and necessary for students of medical schools and infectious diseases doctors, pediatricians, bacteriologists, therapists, pulmonologists, epidemiologists, etc.

[The sensitivity to antibiotics of Corynebacterium non diphtheriae isolated in hospitals of Rostov-on-Don and the Rostovskaia oblast.]

The purpose of study is to analyze sensitivity of various species Corynebacterium non diphtheriaе to antibacterial pharmaceuticals. The strains of C. non diphtheriae are separated from patients with pathology of respiratory and urogenital tract and also from individuals subjected to preventive examination. The sensitivity to antibacterial pharmaceuticals was determined using technique of serial dilution in fluid growth medium on the basis values of minimal inhibitory concentration (mg per l). It is established that the most efficient antibacterial pharmaceuticals in the case of strains C. non diphtheriae proved to be Vancomycin, Cefazolin and Cefotaxime in general. In case of such particular species as С. pseudodiphtheriticum -- Cefazolin, Cefotaxime and Gentamycin; С.pseudotuberculosis -- Vancomycin, Cefazolin, Cefotaxime and Gentamycin; C. xerosis -- Cefotaxime; С.striatum -- Cefazolin and и Rifampicin. The least efficiency was manifested for strains C. non diphtheriae by Benzylpenicillin and Lincomycin in general. In case of such particular species as С. pseudodiphtheriticum and С. pseudotuberculosis -- Lincomycin and Erythromycin; C. xerosis and С. striatum -- Benzylpenicillin, Lincomycin and Erythromycin. In case of various species of C. non diphtheriae Сephalosporins (Cefotaxime and Cefazolin) can be recommended as pharmaceuticals of choice and Gentamycin and Vancomycin as reserve pharmaceuticals.