TY - JOUR AU - Challita, Caren AU - Hafza, Nourhane AU - Dahdouh, Elias AU - Attieh, Michel AU - Dandachi, Iman AU - Daoud, Ziad PY - 2018/02/22 Y2 - 2024/03/29 TI - Carriage trends and fitness cost of MDROs in Lebanese nursing homes JF - The Journal of Infection in Developing Countries JA - J Infect Dev Ctries VL - 12 IS - 02.1 SE - The Lebanese LSIDCM DO - 10.3855/jidc.9996 UR - https://jidc.org/index.php/journal/article/view/31804997 SP - 22S AB - <p>Introduction: Nowadays, medical treatments efficiency is challenged by multi drug resistant organisms (MDROs). Lebanese nursing homes’ residents revealed high fecal carriage rates of MDR <em>Enterobacteriacea</em>. Previous studies claim that bacteria with resistant genes experience fitness cost. This study assesses the competitive growth of MDR <em>Escherichia coli</em> and <em>Klebsiella pneumoniae</em>.</p><p>Methodology: Fecal swabs were collected, during six consecutive months, from ten elderly residing in a Lebanese nursing home. All isolates were subject to API 20E (bioMerieux, Marcy L’ Etoile, France) and antimicrobial susceptibility (Kirby–Bauer method) testing. Phenotypically, ESBL (extended spectrum β-lactamase), MBL (metallo β-lactamase), AmpC and KPC (<em>Klebsiella pneumoniae </em>carbapenemase) were detected using EDTA, PBA, cloxacillin, and DDSTs (Biorad, Hercules, USA). Selected ESBL producing <em>E. coli </em>and <em>K. pneumoniae </em>underwent multiplex PCR analysis. Intra and inter-species <em>in-vitro</em> competition assays were conducted in multiple combinations.</p><p>Results: Among 117 collected isolates, <em>E. coli </em>was predominant (71.8%); 7.7% were ESBL and 5.1% AmpC producers. With <em>E. coli </em>intra-species assays, sensitive isolates out-competed all others, followed by ESBL, AmpC, and OXA-48 (oxacillin) producers. Inter-species assays, demonstrated a decreased fitness of ESBL producing <em>K. pneumoniae</em> in presence of sensitive <em>E. coli</em>. While out-competing ESBL producing <em>E. coli </em>required 2 sensitive <em>K. pneumoniae </em>isolates.</p><p>Conclusion: This study highlights resistant <em>E. coli </em>and <em>K. pneumoniae </em>frequency decrease in presence of sensitive isolates, endorsing the fitness cost hypothesis. &nbsp;Hence, competing supplementary species reproducing gut flora, would ensure further steps in the fight against MDROs.</p> ER -