Evaluation of Biofilm Formation Among Klebsiella pneumoniae Isolates and Molecular Characterization by ERIC-PCR

Abstract

Background:Klebsiella pneumoniae is among the most frequently recovered etiologic agents from nosocomial infections. This opportunistic pathogen can generate a thick layer of biofilm as one of its important virulence factors, enabling the bacteria to attach to living or abiotic surfaces, which contributes to drug resistance.Objectives:The resistance of biofilm-mediated infections to effective chemotherapy has adverse effects on patient outcomes and survival. Therefore, the aim of the present study was to evaluate the biofilm-formation capacity of clinical K. pneumoniae isolates and to perform a molecular characterization using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) to determine the dominant biofilm-producing genotype.Patients and Methods:In the present study, 94 K. pneumoniae isolates were obtained from two hospitals in Tehran, Iran. Biofilm formation was assayed by a modified procedure, then ERIC-PCR was carried out.Results:The distributions of the clinical specimens used in this study were 61.7% from urine, 18.1% from wounds, 11.7% from sputum, and 8.5% from blood. Among these isolates, 33% formed fully established biofilms, 52.1% were categorized as moderately biofilm-producing, 8.5% formed weak biofilms, and 6.4% were non-biofilm-producers. Genotyping of K. pneumoniae revealed 31 different ERIC types. Biofilm-formation ability in a special ERIC type was not observed.Conclusions:Our results indicated that an enormous proportion of K. pneumoniae isolated from sputum and surgical-wound swabs produced fully established biofilms. It is reasonable to assume the existence of a relationship between the site of infection and the formation of biofilm. A high level of genetic diversity among the K. pneumoniae strains was observed.

Biofilm formation and antimicrobial resistance in Klebsiella pneumoniae isolated from patients visiting a tertiary care center of Nepal

“…However, biofilm formation in our study was also observed in high rate in the isolates obtained from other specimens: 83.3%, 71.7% and 66.6% of isolates from pus, urine and sputum, respectively. Our observations were close to those of Seifi et al [15] who also reported that K. pneumoniae isolated from urine, sputum, blood and wound swabs were able to produce biofilm. Detection of biofilm formation even in the isolates originated from OPDs in the present study indicates that K. pneumoniae has the capacity to form biofilm not only on the medical devices used in the hospitalized patients but also directly on the host tissues.…”

“…pneumoniae with the ability to adhere, multiply and persist on inanimate surfaces in the hospital environment has been reported as a significant cause of severe nosocomial infections. Biofilm is the most vital virulence factor in the pathogenesis of this organism [15]. In the present study, we have demonstrated, for the first time, the prevalence of biofilm formation by K. pneumoniae isolated from OPDs and IPDs of tertiary care center of Nepal and their correlation with the antimicrobial resistance pattern.…”

“…Our result was similar to the finding of Mishra et al [16] who elucidated that 75% of K. pneumoniae isolated from various indwelling medical devices formed biofilm. Some previous reports have shown variable data of biofilm such as 93.6% by Seifi et al [15]and 60.3% by Kaur et al[17]. This variation may be due to differences in geographical area, types of specimens, sample sizes, techniques used for detection, etc.…”

First report of coexistence of AmpC beta-lactamase genes in Klebsiella pneumoniae strains isolated from burn patients

“…are among the most frequently isolated bacteria from burning wounds [2]. This organism is one of the most important opportunistic pathogens, causing hospital-acquired and healthcare-associated infections worldwide [3]. In recent decades, due to its tendency to develop antibiotic resistance and increasing virulence factor, lead to emerging this bacterium as clinically important organism [4,5].…”

Study the Effect of some Medical Plants in Biofilm Formation and Antibiotic Sensitivity for Klebsiella Pneumoniae

“…Yang and Zhang (2008) reported the among 150 clinical sample of K. pneumoniae , the 44.7% biofilm formers, 45.3% of them produced ESBLs [29]. Other study indicated all K. pneumoniae isolated from sputum and surgicalwound swabs produced biofilms [30].…”