Various Growth Conditions of Biofilm Associated Extended-Spectrum-Beta-Lactamases Producing Bacteria


Extended-Spectrum β-Lactamase (ESBL) producing bacteria are becoming increasingly prevalent in biofilm associated infections. Bacteria form biofilms that allow their survival in hostile environments. The amount of formed biofilm is affected by external environmental factors. This study investigates the effect of specific parameters (media type, incubation condition, and growth stage) on the amount of produced biofilm on antibiotic resistant bacterial strains, Escherichia coli (CTX-M-15, TEM-3, and IMP-type) and Klebsiella pneumoniae (OXA-48, SHV-18, NDM-1, and KPC-3). The amount of biofilm formed was measured at different time points (6, 12, 24 and 48 h) of incubations under static and shaking conditions, using three different types of media (nutrient broth, LB broth, and AB broth). Statistical tests showed that there was a significant difference in biofilm level (p<0.01) for 64 out of 80 tests (80%) when grown under different types of media. Growing under different incubation conditions also showed a statistical difference in biofilm level (p<0.05) for 76 out of 120 tests (63%). Stage of growth of the same species also showed statistical difference, 20 out of 24 tests (83%) for E. coli and 24 out of 24 tests (100%) for K. pneumoniae. These findings suggested that biofilm formation is highly affected by incubation conditions, strains’ stage of growth, and media type demonstrating that these conditions may play a role in adaptability of the ESBLs on different environmental conditions and their increased prevalence in biofilm associated infections.

Over the years, the increase in the incidence of antibiotic resistance in many pathogens has been reported and in many areas worldwide. This  increase  has  been  attributed  to  the  changing  of  microbial characteristics,  selective  pressure  and  technological  and  social changes that have enhanced the development and spread of antibiotic-resistant  microorganisms.  Despite  being  a  natural  biological  trait, antimicrobial resistance is often enhanced as a result of the adaptation of  the  infectious  agent  to  exposure  to  the  excessive  use  of antimicrobials and/or disinfectants in human or agricultural levels [2].Antibiotic resistance represents one of most significant healthcare problems. The loss of effective antibiotics would weaken the ability to fight infectious diseases and treat the complications for patients with renal  dialysis,  cancer  patients  with  chemotherapy,  and  organ transplantation  surgery,  to  whom  is  the  prevention  of  infections  is critical. Healthcare suppliers are obligated to use more toxic doses of antibiotics,  more  expensive  and  less effective  antibiotics  when  all options have been exhausted, i.e. first and the second line antibiotic treatment is limited by resistance or is unavailable.


Media Contact:

Allison Grey
Journal Manager
Journal of Infectious Diseases and Diagnosis