ABSTRACT
Carbapenemase-producing Enterobacteriaceae (CPE) are well known to cause many serious infections resulting in increasing mortality rate, treatment cost, and prolonged hospitalization. Among the widely recognized types of carbapenemases, New Delhi ß-lactamase (NDM) and Klebsiella pneumoniae carbapenemase (KPC) are the most important enzymes. However, in Vietnam, there are only scattered reports of CPE due to the lack of simple and affordable methods that are suitable to laboratory conditions. This study aims to survey the characteristics of carbapenem-resistant E. coli and K. pneumoniae (CR-E/K) at two hospitals in Southern Vietnam and perform some simple methods to detect the two enzymes. A total of 100 CR-E/K strains were collected from clinical isolates of Gia Dinh People's Hospital and Dong Nai General Hospital, Vietnam, from November 2017 to May 2018. The patient-related information was also included in the analysis. We conducted real-time polymerase chain reaction (PCR), Modified Hodge Test (MHT), and combined disk test (CDT) on all isolates. Carbapenemase-encoding genes were detected in 47 isolates (36 NDM, 10 KPC, and one isolate harboring both genes). The E. coli strain carrying simultaneously these two genes was the first case reported here. Most of isolates were collected from patients in ICU, Infectious Disease Department, and Department of Urologic Surgery. Urine and sputum were two common specimens. The true positive rate (sensitivity, TPR) and specificity (SPC) of the imipenem-EDTA (ethylen diamine tetra acetic acid) for NDM detection and the imipenem-PBA (phenylboronic acid) for KPC detection on E. coli were 93.8%, 97.1% and 66.7%, 95.7%, respectively. Meanwhile, the imipenem-EDTA for NDM detection and the imipenem-PBA for KPC detection among K. pneumonia achieved 90.5%, 100% and 100%, 92.9% TPR and SPC, respectively. However, MHT showed low sensitivity and specificity. Our findings showed that CP-E/K were detected with high prevalence in the two hospitals. We suggest that CDT can be used as a low-priced and accurate method of detection.
Subject(s)
Bacterial Proteins/genetics , Escherichia coli Infections/genetics , Escherichia coli , Klebsiella Infections/genetics , Klebsiella pneumoniae , Polymerase Chain Reaction , beta-Lactamases/genetics , Cross-Sectional Studies , Escherichia coli/enzymology , Escherichia coli/genetics , Escherichia coli/isolation & purification , Escherichia coli Infections/enzymology , Escherichia coli Infections/epidemiology , Female , Humans , Klebsiella Infections/enzymology , Klebsiella Infections/epidemiology , Klebsiella pneumoniae/enzymology , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/isolation & purification , Male , Vietnam/epidemiology , beta-Lactamases/metabolismABSTRACT
BACKGROUND: Antimicrobial resistance has emerged as a major concern in developing countries. The present study sought to define the pattern of antimicrobial resistance in ICU patients with ventilator-associated pneumonia. METHODS: Between November 2014 and September 2015, we enrolled 220 patients (average age ~ 71 yr) who were admitted to ICU in a major tertiary hospital in Ho Chi Minh City, Vietnam. Data concerning demographic characteristics and clinical history were collected from each patient. The Bauer-Kirby disk diffusion method was used to detect the antimicrobial susceptibility. RESULTS: Antimicrobial resistance was commonly found in ceftriaxone (88%), ceftazidime (80%), ciprofloxacin (77%), cefepime (75%), levofloxacin (72%). Overall, the rate of antimicrobial resistance to any drug was 93% (n = 153/164), with the majority (87%) being resistant to at least 2 drugs. The three commonly isolated microorganisms were Acinetobacter (n = 75), Klebsiella (n = 39), and Pseudomonas aeruginosa (n = 29). Acinetobacter baumannii were virtually resistant to ceftazidime, ceftriaxone, piperacilin, imipenem, meropenem, ertapenem, ciprofloxacin and levofloxacin. High rates (>70%) of ceftriaxone and ceftazidime-resistant Klebsiella were also observed. CONCLUSION: These data indicated that critically ill patients on ventilator in Vietnam were at disturbingly high risk of antimicrobial resistance. The data also imply that these Acinetobacter, Klebsiella, and Pseudomonas aeruginosa and multidrug resistance pose serious therapeutic problems in ICU patients. A concerted and systematic effort is required to rapidly identify high risk patients and to reduce the burden of antimicrobial resistance in developing countries.
