Evaluation of Antimicrobial Resistance Rates in Klebsiella Isolates

Abstract

Introduction: Bacteria of the genus Klebsiella are important causes of nosocomial infections. These bacteria may develop resistance in different ways, with extended-spectrum beta-lactamase (ESBL) production being the most common. The aim of this study was to evaluate resistance status of Klebsiella isolates obtained from different intensive care units and various clinical samples. Materials and Methods: Resistance rates of Klebsiella spp. strains isolated from bacteriologic cultures of patients in intensive care units between 2014 and the first six months of 2017 were evaluated retrospectively. Blood, urine, bronchoalveolar lavage, cerebrospinal fluid, and tracheal aspirate samples were cultured. Intensive care patients aged ≥18 years were included. Only the first isolate from each patient was included; subsequent isolates from the same patient were excluded. Results:A total of 443 patients were included in the study. Of the Klebsiella-positive samples, 31.8% (n=141) were tracheal aspirate, 23.7% (n=105) were blood, 23.3% (n=103) were urine, 9.0% (n=40) were sputum, and 12.2% (n=54) were other samples. The majority of cases were K. pneumoniae (89.7%, n=397), followed by K. oxytoca (7%, n=31), K. ozaenae (2.9%, n=13), K. granulomatis (0.2%, n=1), and K. ornithinolytica (0.2%, n=1). Of the 443 isolates, 54.4% (n=241) were ESBL-producing while 45.6% (n=202) were non-ESBL-producing. Mortality rates were 60% among patients with ESBL-positive Klebsiella and 47.5% among patients with ESBL-negative Klebsiella (p=0.008). Conclusion: The antibiotic resistance of ESBL-positive Klebsiella isolates in our hospital was higher than resistance rates in the literature. To overcome this resistance issue, each hospital must know its own resistance rates and establish policies for the rational use of antibiotics.

Keywords

• Extended-spectrum beta-lactamase
• Klebsiella
• ciprofloxacin
• colistin
• tigecycline