Community-Acquired Pneumonia in Infectious Hospital Patients: The Development of Resistance to Antimicrobials

Abstract

The aim of the work was to study the structure, level and dynamics of resistance to antimicrobial drugs of the most common types of microorganisms in patients with community-acquired pneumonia (CAP) in the Krasnodar Territory, on the example of patients treated in a regional specialized infectious hospital for the period 2015-2017. Materials and methods. The results of bacteriological tests of expectoration, including 523 positive strains of microorganisms, are analyzed. The analysis does not include strains with hospital multidrug resistance. A bacterioscopy with Gram stain and sputum seeding on plate-like artificial nutrient media were carried out. Identification of the pathogen was performed by mass spectrometry using MALDI-TOF technology (Microflex LT, Bruker, Germany), phenotypically identified resistance mechanisms were confirmed on the automatic analyzer Vitek II Compact (BioMérieux, France). The sensitivity to antimicrobials was determined by the disc-diffusion method in the Müller-Hinton medium, using the disks by Bio-Rad, France. The antibioticogram was analyzed on the apparatus “Adagio” (Bio-Rad, France). Results. In the etiologic structure of community-acquired pneumonia, Streptoccocus pneumonia prevails in patients hospitalized in an infectious hospital in the Krasnodar Territory, which is determined in 73.56% of confirmed cases, which is twice as high as an average in Russia. Staphylococcus aureus was determined in 9.04% of casesd, with fluctuations in different years from 3.8% to 12.1%. Klebsiella pneumoniae was found in 4.61%, with variations from 1.7% to 9.3%. Pseudomonas aeruginosa was registered in 4.6%, altered from 1.3% to 7.8%. Other microorganisms were represented with Enterobacteriaceae family, 8.2% of the cases. The resistance of wild strains of microorganisms isolated at CAP to a number of antimicrobial agents has been established. A number of negative trends were noted: the emergence of pneumococcal strains resistant to beta-lactam antimicrobial drugs (benzylpenicillin MIC < 2μg); an increase in the resistance of pneumococci to macrolides, tetracyclines, sulfonamides. There is a high percentage of Staphylococcus aureus (80%) producing penicillinase, and an increase in their resistance to macrolides. A high level of Pseudomonas aeruginosa resistance to 3-rd and 4-th generation cephalosporins is noted. Conclusion. The obtained data determine the need for further monitoring of regional resistance of microorganisms, which will allow both adequate start therapy and the possibility of its timely correction. In the practical work of a doctor, it is important not only to be guided by local data on the resistance of microorganisms to antimicrobial drugs, but also to analyze the possible causes of its occurrence with the establishment of individual risk factors.