Study of an outbreak of cefoxitin-resistant Klebsiella pneumoniae in a general hospital

Abstract

During a 3-month period, six Klebsiella pneumoniae isolates resistant to cefoxitin and penicillin-inhibitor combinations were derived from patients in the intensive care unit of a hospital in Athens, Greece. Enterobacterial repetitive intergenic consensus PCR and pulsed-field gel electrophoresis provided evidence of the clonal origin of the isolates. Conventional techniques and ribotyping were inadequate in proving that the isolates were related. Resistance was due to a plasmidic class C ␤-lactamase.

Therapeutic Challenges Associated with Extended‐Spectrum, β‐Lactamase‐Producing Escherichia coli and Klebsiella pneumoniae

“…Of note, treatment failure with cephamycins may result from in vivo selection of porin-deficient mutants during therapy. 45,46 Also, isolates that harbor additional mechanism of resistance such as plasmid-mediated AmpC ␤lactamases may not respond to cephamycins. Considering the relative stability of cefepime against AmpC ␤-lactamases, it may be a reasonable alternative for treatment of infections due to an isolate harboring resistance determinants for both TEM and SHV and AmpC ␤-lactamases if the isolate shows apparent in vitro susceptibility to the drug.…”

Association of Antibiotic Utilization Measures and Control of Multiple-Drug Resistance inKlebsiella pneumoniae

“…Typing studies have documented that isolates from MDR/f pneumoniae outbreaks have represented both clonal and polyclonal strains. [3][4][5][6] Although traditional infection control measures such as Contact Precautions are the primary means to prevent clonal transmission, antibiotic-control measures may be important in decreasing polyclonal transmission. In particular, decreased ceftazidime use has been associated with decreased institutional prevalence of ESBLproducing K pneumoniae.…”

Extended-Spectrum Beta-Lactamases

“…However, there a number of reports of ESBL-producing strains with coexisting AmpC-type beta-lactamases that demonstrate resistance to the cephamycins as well. 20,34,35 Organisms containing AmpC-type beta-lactamases are characteristically resistant to the cephamycins and to inhibition by beta-lactamase inhibitor combinations such as piperacillin/tazobactam, ampicillin/sulbactam, and ticarcillin/clavulanate. In addition, there has also been a report of emergence of a cephamycin-resistant, porin-deficient mutant during therapy with a cephamycin.…”

“…The authors also suggest that the emergence of the TEM-3 ESBL in France has been primarily by plasmid dissemination compared with the emergence of SHV-4 in France that has been primarily due to clonal strain dissemination. 55 Many instances of clonal strain transmission are reported as the primary mechanism for ESBL outbreaks as well, 34,[56][57][58][59][60][61] including outbreaks involving multiple hospitals in a geographic area. 60,61 Thus, patient-to-patient spread of strains remains a significant mechanism of emergence for this type of resistance.…”