Antibiotic resistance profile of Klebsiella pneumoniae strains isolated in an infectious diseases clinic

Abstract

Objective. To establish the resistance profile of Klebsiella pneumoniae (KP) strains isolated in the Craiova Infectious Diseases Clinic. Material and method. Retrospective study (January 2017-December 2018); KPs were identified using the automated Vitek 2 system, which subsequently established their susceptibility to antimicrobials (usual testing for 17 antibiotics, extended testing for another 9); for each strain the multiple antibiotic resistance index (MAR) was calculated (limits: 0-1); the information was entered into an Excel database. 45 strains were tested in 2017 and 290 in 2018. The percentage of MDR strains was calculated based on internationally accepted definitions. Results. 335 strains were identified, the vast majority isolated by sputum culture (192 strains - 57.31%). Demographic data: 330 strains (99%) were isolated in adult subjects, 190 (57%) in male patients, 185 (55%) in patients living in urban areas. The overall value of MAR was 0.37 (compared to 0.32 for all strains of isolated Gram-negative germs). Over 80% of KP strains were susceptible to Amikacin or Polymyxin E; susceptibilities between 60 and 79% were observed for Meropenem, Gentamicin, Tobramycin, Ciprofloxacin, Ertapenem, Trimethoprim-Sulfamethoxazole, Levofloxacin, Cefepima, and between 40 and 59% for Ceftriaxone, Cefoxitin, Ceftazidime, Minocycline and Im. Less than 39% of strains are susceptible to Ampicillin (± Sulbactam), Piperacillin (± Tazobactam), Ticarcillin (± Clavulanic acid), Aztreonam, Pefloxacin, Cefazolin, Nitrofurantoin. Resistance to the main classes of antibiotics shows lower values than national and european data for 3rd generation cephalosporins, fluoroquinolones and aminoglycosides, but a much higher percentage of resistance to carbapenems. Over 68% of isolates are multidrug-resistant (MDR); over 60% of the strains come from sources where there is a significant contact with antimicrobials. Conclusions. Over 80% of the isolated strains are sensitive to Amikacin or Polymyxin E; a percentage of over 29% of the strains demonstrates resistance to the carbapenem class in 2018; over 68% of isolates are multidrug-resistant; over 60% of the strains come from sources where there is significant contact with antimicrobials.

Keywords

• klebsiella pneumoniae
• antimicrobial resistance
• mar