Strain Typing and Molecular Characterization of CTX-M-1 Group ESBL in Clinical Klebsiella pneumoniae Isolated from Children

Abstract

Background: Extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae is rapidly spreading worldwide, creating se-

<p>Dissemination Pattern of Multidrug Resistant Carbapenemase Producing <em>Klebsiella pneumoniae</em> Isolates Using Pulsed-Field Gel Electrophoresis in Southwestern Iran</p>

“…24 In another study in Kurdistan, Iran, PFGE analysis of K. pneumoniae isolates was performed, and they identified 11 various profiles and one major clone, and transmission between patients and different wards was also proposed. 36 According to a previous study, environmental reservoirs in hospitals can cause the transmission of different bacteria and antibiotic resistance in different wards. 25 As previously reported, antimicrobial resistance genes can easily spread among different species and strains and distribute among the hospital wards.…”

Whole Genome Characterization of the High-Risk Clone ST383 Klebsiella pneumoniae with a Simultaneous Carriage of blaCTX-M-14 on IncL/M Plasmid and blaCTX-M-15 on Convergent IncHI1B/IncFIB Plasmid from Egypt

“…Expanded-spectrum cephalosporins are still among the most globally prescribed antimicrobial agents [5]. This extensive usage has been mirrored by a global expansion of extended-spectrum β-lactamase (ESBL)-producing K. pneumoniae showing resistance to ceftriaxone, cefotaxime, ceftazidime, and monobactams (as aztreonam), reaching 50% in some countries [4,6]. At a national level, a surveillance study carried out in five hospitals in Cairo, from 1999 to 2000, showed reduced susceptibility of Klebsiella spp.…”

“…In recent years, the repetitive use of cefotaxime and ceftazidime in therapy regimens for infections due to ESBL-producing K. pneumoniae has induced the emergence of K. pneumoniae harboring the most widespread type of ESBLs, the CTX-M-β-lactamases [6]. Based on their amino acid sequence identities, this group of molecular class A ESBLs has been subdivided into five clusters (from Group I to Group V) all possessing superior hydrolytic activity against ceftriaxone and cefotaxime [9] rather than ceftazidime [6].…”

“…In recent years, the repetitive use of cefotaxime and ceftazidime in therapy regimens for infections due to ESBL-producing K. pneumoniae has induced the emergence of K. pneumoniae harboring the most widespread type of ESBLs, the CTX-M-β-lactamases [6]. Based on their amino acid sequence identities, this group of molecular class A ESBLs has been subdivided into five clusters (from Group I to Group V) all possessing superior hydrolytic activity against ceftriaxone and cefotaxime [9] rather than ceftazidime [6]. Group I comprises CTX-M-1, -3, -10, -11, -12, -15, -22, -23, -28, -29, and -30; Group II includes CTX-M-2, -4, -5, -6, -7, and -20, and Toho-1; Group III consists of CTX-M-8; Group IV comprises CTX-M-9, -13, -14, -16, -17, -18, -19, -21, and -27, and Toho-2; the last group, group V, includes CTX-M-25 and -26 [9].…”

“…Group I comprises CTX-M-1, -3, -10, -11, -12, -15, -22, -23, -28, -29, and -30; Group II includes CTX-M-2, -4, -5, -6, -7, and -20, and Toho-1; Group III consists of CTX-M-8; Group IV comprises CTX-M-9, -13, -14, -16, -17, -18, -19, -21, and -27, and Toho-2; the last group, group V, includes CTX-M-25 and -26 [9]. Massive nosocomial outbreaks due to CTX-M-producing K. pneumoniae have been described in different continents including Africa [6,10]. Apparently, highly mobilizable genetic platforms and epidemic spreading of particular strains have fueled this vast and accelerated dispersion of bla CTX-M [11].…”