Identification of extended-spectrum-β-lactamase-positive Klebsiella pneumoniae urinary tract isolates harboring KPC and CTX-M β-lactamases in nonhospitalized patients.

Forty-seven extended-spectrum-β-lactamase-positive Klebsiella pneumoniae urinary tract isolates from nonhospitalized patients were identified, and 79% harbored KPC and/or CTX-M β-lactamases. Approximately 90% of the isolates were resistant to trimethoprim-sulfamethoxazole and levofloxacin, and 40% were resistant to a carbapenem, while 92% were susceptible to polymyxin B, 87% were susceptible to tigecycline, and 79% were susceptible to fosfomycin. Increased use of broader-spectrum antibiotics may help to prevent their dissemination and reduce the risk of progression to invasive disease.

Identification of CTX-M β-lactamases among Escherichia coli from the community in New York City.

We have identified CTX-M group 1 β-lactamases in 87% of community-acquired Escherichia coli isolates that produce extended-spectrum β-lactamases, with the majority harboring CTX-M-15 and representing the ST131 clonal group. Seventy percent of CTX-M-bearing isolates were from urine specimens; a large proportion was nonsusceptible to levofloxacin, trimethoprim/sulfamethoxazole, and β-lactam antimicrobials. Many patients were relatively youthful (41% ≤65 years old; youngest, age 32).

Phenotypic and genotypic screening and clonal analysis of carbapenem-resistant Klebsiella pneumoniae at a single hospital.

Detection of bla(KPC)-harboring Klebsiella pneumoniae (KP) in the clinical laboratory remains a difficult task. Decreased ertapenem (ERT) susceptibility has been considered one of the most sensitive phenotypic indicators of K. pneumoniae carbapenemase (KPC) production, but has been found to be nonspecific.

Polymyxin-resistant clinical isolates of Escherichia coli.

A surveillance study to identify patients from the community with Escherichia coli resistant to broad-spectrum cephalosporins discovered two isolates that were also resistant to polymyxin B and colistin. One isolate from a patient in the community and a second from a patient who received multiple courses of polymyxin B also possessed a CTX-M-15 enzyme. Resistance to cationic peptides in E.

Identification of CTX-M beta-lactamases in Escherichia coli from hospitalized patients and residents of long-term care facilities.

Bacteria harboring CTX-M extended-spectrum beta-lactamases (ESBLs) have been identified worldwide, with most reports coming from regions outside North America. We have identified CTX-M enzymes in 31% of ESBL-positive Escherichia coli isolates from our hospital and more than half (53%) of the isolates from associated long-term care facilities. Approximately 3/4 of all CTX-M-bearing isolates were from urine specimens, with a predominance of CTX-M-15.

Carbapenem-resistant Escherichia coli harboring Klebsiella pneumoniae carbapenemase beta-lactamases associated with long-term care facilities.

Nine carbapenem-resistant Escherichia coli isolates harboring Klebsiella pneumoniae carbapenemase (KPC)-2 or KPC-3 enzymes were identified in patients residing in 7 distinct long-term care facilities. Cefotaxime-hydrolyzing (CTX-M)-type beta-lactamases were also documented in 3 isolates. The identification of these enzymes in patients staying in long-term care facilities should be of great concern to all components of health care systems.

Identification of carbapenem-resistant klebsiella pneumoniae harboring KPC enzymes in New Jersey.

Klebsiella pneumoniae isolates harboring KPC enzymes have been identified in many geographical areas since 2001. Numerous problems exist in the detection and treatment of patients with such isolates. The clinical characteristics and molecular epidemiology associated with 12 randomly chosen patients in whom these enzymes were detected by molecular methods are described.