Fosfomycin-resistant FosA8-producing Enterobacterales are uncommon strains with extremely low incidence in Europe, based on only three reports in the literature. We detected FosA8-producing Escherichia coli ST131 in clinical isolates from two patients admitted in February 2023 to a rehabilitation unit in Italy. The occurrence of rare fosA-like genes in the high-risk clone ST131 is of clinical relevance. The dissemination of FosA-producing E. coli, although still at low levels, should be continuously monitored.

• Klíčová slova
• E. coli ST131, FosA8, Fosfomycin, Fosfomycin resistance,,
• MeSH
• antibakteriální látky * farmakologie   terapeutické užití   MeSH
• bakteriální léková rezistence MeSH
• beta-laktamasy genetika   metabolismus   MeSH
• Escherichia coli * izolace a purifikace   genetika   účinky léků   MeSH
• fosfomycin farmakologie   terapeutické užití   MeSH
• infekce vyvolané Escherichia coli * mikrobiologie   epidemiologie   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• multilokusová sekvenční typizace MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Geografické názvy
• Itálie epidemiologie   MeSH
• Názvy látek
• antibakteriální látky * MeSH
• beta-laktamasy MeSH
• fosfomycin MeSH

Antimicrobial resistance is well-known to be a global health and development threat. Due to the decrease of effective antimicrobials, re-evaluation in clinical practice of old antibiotics, as fosfomycin (FOS), have been necessary. FOS is a phosphonic acid derivate that regained interest in clinical practice for the treatment of complicated infection by multi-drug resistant (MDR) bacteria. Globally, FOS resistant Gram-negative pathogens are raising, affecting the public health, and compromising the use of the antibiotic. In particular, the increased prevalence of FOS resistance (FOSR) profiles among Enterobacterales family is concerning. Decrease in FOS effectiveness can be caused by i) alteration of FOS influx inside bacterial cell or ii) acquiring antimicrobial resistance genes. In this review, we investigate the main components implicated in FOS flow and report specific mutations that affect FOS influx inside bacterial cell and, thus, its effectiveness. FosA enzymes were identified in 1980 from Serratia marcescens but only in recent years the scientific community has started studying their spread. We summarize the global epidemiology of FosA/C2/L1-2 enzymes among Enterobacterales family. To date, 11 different variants of FosA have been reported globally. Among acquired mechanisms, FosA3 is the most spread variant in Enterobacterales, followed by FosA7 and FosA5. Based on recently published studies, we clarify and represent the molecular and genetic composition of fosA/C2 genes enviroment, analyzing the mechanisms by which such genes are slowly transmitting in emerging and high-risk clones, such as E. coli ST69 and ST131, and K. pneumoniae ST11. FOS is indicated as first line option against uncomplicated urinary tract infections and shows remarkable qualities in combination with other antibiotics. A rapid and accurate identification of FOSR type in Enterobacterales is difficult to achieve due to the lack of commercial phenotypic susceptibility tests and of rapid systems for MIC detection.

• Klíčová slova
• Enterobacterales, epidemiology, fosfomycin, fosfomycin-resistance, fosfomycin-resistant determinant,
• MeSH
• antibakteriální látky farmakologie   MeSH
• bakteriální léková rezistence genetika   MeSH
• Escherichia coli genetika   MeSH
• fosfomycin * farmakologie   MeSH
• Klebsiella pneumoniae genetika   MeSH
• proteiny z Escherichia coli * genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• antibakteriální látky MeSH
• fosfomycin * MeSH
• proteiny z Escherichia coli * MeSH