Evaluation of Antibiotic Resistance and Biofilm Production among Clinical Strain Isolated from Medical Devices.

Veronica Folliero,Federica Dell’Annunziata,Gianluigi Franci,Francesco Foglia,Emiliana Finamore,Rossella Sperlongano,Rosa Giugliano,Anna De Filippis,Massimiliano Galdiero,Joseph Falkinham

doi:10.1155/2021/9033278

Abstract

Microbial biofilms pose a serious threat to patients requiring medical devices (MDs). Prolonged periods of implantation carry a high risk of device-related infections (DRIs). Patients with DRIs often have negative outcomes following the failure of antibiotic treatment. Resistant DRIs are mainly due to the MDs contamination by bacteria producing biofilm. The present study aimed to detect biofilm formation among MD bacterial isolates and to explore their antibiotic resistance profile. The study was conducted on 76 MDs, collected at University Hospital of Campania “Luigi Vanvitelli,” between October 2019 and September 2020. Identification of isolates and antibiotic susceptibility testing were performed using Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) and Phoenix Becton Dickinson, respectively. Biofilm-forming abilities were assessed using the tissue culture plate (TCP) method. Among the 94 MDs isolated strains, 42.7% were Gram-positive, 40.3% Gram-negative, and 17% Candida species. Among 78 bacterial strains, 43.6% were non-biofilm producers while 56.4% produced biofilms. All biofilm producing isolates were sensitive to a limited spectrum of antibiotic classes. All moderate and strong biofilm producers and 81% of weak biofilm producers were Multidrug Resistance (MDR) strains. In contrast, among non-biofilm producers, only 11.8% were classified as MDR strains. Our results highlighted that Sulfamides and Glycopeptides for the major Gram-positive strains and Fluoroquinolones, Carbapenems, and Aminoglycosides for the most represented Gram-negative isolates could be the most suitable therapeutic choice for most biofilm-DRIs.

Highlights

Biofilm is a structured bacterial community, enclosed in a selfproduced polymeric matrix and adhered to biotic or abiotic surfaces [1]
Foley’s catheter tips were mainly colonized by P. aeruginosa (25%), succeeded by Enterococcus species (16.7%), K. pneumoniae (16.7%), and E. coli (16.7%), coagulase-negative staphylococci (CoNS) strains (8.3%), P. mirabilis (8.3%), and Candida species (8.3%). e current analysis revealed that some devices were colonized by more than one microorganism. e monomicrobial contaminations accounted for 77.6%, while polymicrobial growths were detected in 22.4% of devices with 19.8 and 2.6% for bimicrobial and trimicrobial contaminations, respectively
Fungal/bacterial and bacterial/ bacterial copresence were each associated with a prevalence of 41.2 and 58.8%. e devices subject to the greatest polymicrobial contamination were central venous catheters (CVCs), showing the copresence of Candida species with CoNS, Enterococcus strains, P. aeruginosa, S. agalactiae, and K. pneumoniae

Summary

Introduction

Biofilm is a structured bacterial community, enclosed in a selfproduced polymeric matrix and adhered to biotic or abiotic surfaces [1]. Compared to their planktonic counterparts, biofilm-associated bacteria exhibit greater resistance to antibiotic agents [2]. Abidi et al showed that biofilm production was higher among MDR Pseudomonas aeruginosa (P. aeruginosa) strains than non-MDR strains [6]. Qayoom et al found that the Acinetobacter baumannii (A. baumannii) MDR produced more biofilm than the non-MDR ones [7]. Regarding Staphylococcus aureus (S. aureus), Manandhar et al associated biofilm production with Methicillin resistance [8, 9]

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Conclusion