Nosocomial coagulase-negative staphylococci in Belgrade: between Scylla and Charybdis

Abstract

Introduction: Coagulase-negative staphylococci (CoNS) are increasingly resistant nosocomial pathogens. We aimed to analyze the prevalence of CoNS isolates in clinical settings, the evolution of antimicrobial resistance of CoNS, and antibiotic consumption in a hospital. Methodology: This retrospective cohort study was carried out at a tertiary healthcare facility over 17 months. Identification of isolated cultures and antibiotic susceptibility testing were performed using the Vitek2 system. Of 1,217 isolates, 209 were obtained from 193 patients who had symptoms of nosocomial infections. Data were analyzed by descriptive statistics. Antibiotic consumption in the hospital is expressed in defined daily doses/100 patient days. Results: Sixty-one percent of patients were admitted to the internal medicine ward, while others were admitted to the surgical ward. Forty-four percent of Gram-positive isolates were from wound swabs, and 26% were from blood. The predominant Gram-positive bacteria were CoNS. Antibiotic resistance of CoNS was highest against beta-lactam antibiotics, macrolides, and tetracyclines. Tigecycline, linezolid, and vancomycin produced the highest activities against CoNS in in vitro conditions, and consumption of linezolid and tigecycline increased in the same period. Conclusion: There are just a few remaining therapeutic options for the treatment of CoNS according to our results; vancomycin, linezolid, and tigecycline might be considered as first-choice antibiotics, but such a hypothesis should be supported with a pharmacoeconomic analysis. Unfortunately, novel antimicrobial agents are still unavailable and/or too expensive in developing countries. However, inappropriate use of those antibiotics may lead to the rapid development of resistant strains in the near future.

Analysis of the third- and fourth-generation cephalosporin use for the treatment of infections caused by Gram-negative bacteria in hospital settings

“…Longer hospitalisation was confirmed as a risk factor for the occurrence of nosocomial infections caused by multiresistant strains of bacteria. 20,24 Another risk factor for the poor outcome of hospitalised patients, a more common comorbidity, was more prevalent in the sample from BK. This probably contributed to a more frequent occurrence of sepsis caused by G-bacteria, and together with the more frequent use of mechanical ventilation contributed to a significant occurrence of G-lower respiratory tract infections in BK (Table 4).…”

“…Demographic characteristics of adult patients at two hospital centres expectedly were different: in BK as a third‐level medical establishment which carries out highly specialised consulting and stationary, educational‐teaching and scientific research activity, patients treated with third‐ and fourth‐generation cephalosporins were older, hospitalisation lasted longer, as the period prior to first isolation of G‐ bacteria. Longer hospitalisation was confirmed as a risk factor for the occurrence of nosocomial infections caused by multiresistant strains of bacteria . Another risk factor for the poor outcome of hospitalised patients, a more common comorbidity, was more prevalent in the sample from BK.…”

Staphylococcal biofilm on wedding rings worn by laboratory workers

“…In the previous study performed among patients in a Belgrade tertiary care hospital, susceptibility patterns of coagulase-negative staphylococci were investigated, and the obtained results showed that 70% of the strains were resistant to penicillin, 50% to erythromycin, 40% to clindamycin and 55% to tetracycline [26]. Although similar susceptibility profile was detected in both research, advantages of our investigation is identification of the coagulase-negative staphylococci to the species level and, additionally, determination of the strains sensitivity only to antistaphylococcal antibiotics.…”