Detection of Biofilm Production and Antibiotic Resistance Pattern in Clinical Isolates from Indwelling Medical Devices

Abstract

Microbial biofilms pose great threat for patients requiring indwelling medical devices (IMDs) as it is difficult to remove them. It is, therefore, crucial to follow an appropriate method for the detection of biofilms. The present study focuses on detection of biofilm formation among the isolates from IMDs. We also aimed to explore the antibiogram of biofilm producers. This prospective analysis included 65 prosthetic samples. After isolation and identification of bacteria following standard methodology, antibiogram of the isolates were produced following Kirby-Bauer disc diffusion method. Detection of biofilms was done by tube adherence (TA), Congo red agar and tissue culture plate (TCP) methods. Out of 67 clinical isolates from IMDs, TCP detected 31 (46.3 %) biofilm producers and 36 (53.7 %) biofilm non-producers. Klebsiella pneumoniae, Pseudomonas aeruginosa and Burkholderia cepacia complex were found to be the most frequent biofilm producers. The TA method correlated well with the TCP method for biofilm detection. Higher antibiotic resistance was observed in biofilm producers than in biofilm non-producers. The most effective antibiotics for biofilm producing Gram-positive isolates were Vancomycin and Tigecycline, and that for biofilm producing Gram-negative isolates were Polymyxin-B, Colistin Sulphate and Tigecycline. Nearly 46 % of the isolates were found to be biofilm producers. The antibiotic susceptibility pattern in the present study showed Amoxicillin to be an ineffective drug for isolates from the IMDs. For the detection of biofilm production, TA method can be an economical and effective alternative to TCP method.

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

“…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].…”

“…All the biofilm negative strains were sensitive to imipenem, ertapenem, polymyxin B, and chloramphenicol whereas biofilm positive strains exhibited resistance of 4.5%, 2.2%, 4.5%, and 18.1%, respectively against them. The higher incidence of antibiotic resistance in biofilm producers than in the biofilm non-producers was also reported by Mishra et al [16] and Naparstek et al [21]. Our observation also concurs with a finding of a prospective analysis that has revealed higher resistance rates against nalidixic acid, ampicillin, cefotaxime and co-trimoxazole among the biofilm positive isolates compared to biofilm negative isolates [22].…”

“…This may be attributed by the use of medical devices among hospitalized patients. Medical implants and catheters are particularly susceptible to biofilm formation by K. pneumoniae because immune responses are significantly reduced in proximity to foreign bodies [16]. In the present study, all three isolates originated from medical devices (ET) tubes were found to be the biofilm producers.…”

Global gene expression in Escherichia coli, isolated from the diseased ocular surface of the human eye with a potential to form biofilm

“…Out of these ten antibiotic tolerant ocular E. coli , majority of the isolates (8/10) were positive for biofilm formation by the TCP method thus implying a close association between antibiotic tolerance and biofilm formation [36, 37]. Surprisingly we also observed that E. coli L-2561/2013 from the vitreous fluid of Endophthalmitis patients was not resistant to any one of the antibiotics tested but possessed the ability to form biofilm.…”

Klebsiella pneumoniae: Going on the Offense with a Strong Defense

“…In part due to their fimbriae (see below), some K. pneumoniae strains are very sticky and attach to medical devices (116)(117)(118)(119). One frequent route of acquisition of K. pneumoniae pneumonias is through endotracheal intubation, which increases the risk of acquiring K. pneumoniae ventilator-associated pneumonia (VAP), a form of nosocomial pneumonia that develops at least 48 h postintubation (11).…”