Combination antibiotic therapy for treatment of a patient with infected prosthesis and peri-prosthetic abscess due to harboring New Delhi Metallo (NDM) beta-lactamase.

Treatment options for patients infected with multi-drug resistant gram-negative bacteria harboring metallo-beta-lactamases (MBLs) requires precision therapy. We present the case of a 20 year-old male with a right distal femoral peri-prosthetic abscess with presumed infected hardware and osteomyelitis in whom four multi-drug resistant gram negative bacteria were isolated. The rapid identification of an MBL producing organism, novel combination of therapy, and prompt infection prevention enforcement and education led to appropriate treatment of our patient as well as prevention of spread of organisms during and after hospitalization.

Successful Treatment of Harboring a Carbapenemase Isolated from Lumbar Wound Infection and Blood in a Patient with Hardware Retention.

Infections caused by carbapenem-resistant Enterobacteriaceae, especially carbapenemase producing , represent an urgent threat as outlined by the Centers for Disease Control and Prevention (CDC). We present a 66-year-old male with spinal stenosis who underwent elective L2-pelvis posterior spinal fusion at an outside institution and rapidly developed a complicated infection with harboring carbapenemase. This is the first described case of a patient with harboring carbapenemase causing postoperative lumbar wound infection and bacteremia, successfully treated with ceftazidime-avibactam in combination with additional synergistic antibacterials and without hardware removal.

Unrelated strain methicillin-resistant Staphylococcus aureus colonization of health care workers in a neonatal intensive care unit: findings of an outbreak investigation.

Three neonates and 5 health care workers were identified as colonized with methicillin-resistant Staphylococcus aureus (MRSA) out of 222 individuals screened during an outbreak investigation in an 18-bed neonatal intensive care unit. Two of 3 MRSA neonatal isolates demonstrated identical pulsed-field gel electrophoresis clonal patterns but no clonal association was found among isolates from the 5 employees or between employees and neonates. Increased MRSA-unrelated strain colonization among health care workers supports increased MRSA community prevalence and probable decreased utility of mass screening.

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.

Use of daptomycin for the treatment of methicillin-resistant coagulase-negative staphylococcal ventriculitis.

Coagulase-negative staphylococci (CoNS) are the main pathogens causing hospital-acquired external-ventricular-drain- (EVD-) and lumbar-drain- (LD-) associated meningitis and ventriculitis. The treatment of these infections can be challenging and may require combination of intraventricular and intravenous administration of antibiotics. Limited animal data demonstrate rapid daptomycin bactericidal activity, adequate penetration in the setting of inflamed meninges, and extended half-life in the ventricles Steenbergen et al.

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).

Polymyxin Combination Therapy and the Use of Serum Bactericidal Titers in the Management of KPC-Producing Klebsiella pneumoniae Infections: A Report of 3 Cases.

Management of patients with KPC-harboring Enterobacteriaceae has become a significant and challenging scenario. We report three cases of KPC-producing Klebsiella pneumoniae bacteremia that were successfully treated using combination therapy with polymyxin B and other antimicrobials. Serum bactericidal titers were determined and provided additional clinical guidance in the management of such patients.

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.

In vitro double and triple bactericidal activities of doripenem, polymyxin B, and rifampin against multidrug-resistant Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli.

In vitro double and triple bactericidal activities of doripenem, polymyxin B, and rifampin were assessed against 20 carbapenem-resistant clinical isolates with different mechanisms of carbapenem resistance. Bactericidal activity was achieved in 90% of all bacteria assayed using combinations of polymyxin B, doripenem, and rifampin against five each of the carbapenem-resistant Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli isolates studied. Combinations with these antibacterials may provide a strategy for treatment of patients infected with such organisms.

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.

Impact of contact and droplet precautions on the incidence of hospital-acquired methicillin-resistant Staphylococcus aureus infection.

Objective: To evaluate the efficacy of contact and droplet precautions in reducing the incidence of hospital-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections.

Design: Before-after study.Setting.

Fluoroquinolone-resistant Streptococcus agalactiae: epidemiology and mechanism of resistance.

Quinolone-resistant Streptococcus agalactiae bacteria were recovered from single-patient isolates and found to contain mutations in the gyrase and topoisomerase IV genes. Pulsed-field gel electrophoresis demonstrated that four isolates from the same long-term care facility were closely related; in seven cases, quinolone-resistant Haemophilus influenzae and S. agalactiae bacteria were isolated from the same patient.

Increased mortality associated with a clonal outbreak of ceftazidime-resistant Klebsiella pneumoniae: a case-control study.

Objectives: To determine risk factors for ceftazidime-resistant Klebsiella pneumoniae infection and the effect of ceftazidime-resistant K. pneumoniae infection on mortality during an isolated outbreak.

Design: Case-control investigation using clinical and molecular epidemiology and prospective analysis of infection control interventions.

Quinolone-resistant Haemophilus influenzae: determination of mutant selection window for ciprofloxacin, garenoxacin, levofloxacin, and moxifloxacin.

Stepwise selection of ciprofloxacin-resistant Haemophilus influenzae mutants produced first-, second-, third-, and fourth-step substitutions in GyrA (S84Y), ParC (S84R), GyrA (D88N), and ParC (E88K), respectively. Successive mutations raised the mutant selection window. The wild-type selection window for garenoxacin, levofloxacin, and moxifloxacin was also measured.

Quinolone-resistant Haemophilus influenzae in a long-term-care facility: nucleotide sequence characterization of alterations in the genes encoding DNA gyrase and DNA topoisomerase IV.

Fluoroquinolone-resistant isolates of Haemophilus influenzae, obtained from a long-term care facility, were examined for nucleotide sequence differences in the quinolone-resistance-determining regions of gyrA, gyrB, parC, and parE. Similarities among the resistant isolates, plus multiple differences with susceptible isolates, suggest clonal dissemination involving two resistant subclones.

Emergence of carbapenem-resistant Klebsiella species possessing the class A carbapenem-hydrolyzing KPC-2 and inhibitor-resistant TEM-30 beta-lactamases in New York City.

Nineteen isolates of carbapenem-resistant Klebsiella species were recovered from 7 hospitals in New York City. Most K. pneumoniae belonged to a single ribotype.

Quinolone-resistant Haemophilus influenzae in a long-term care facility: clinical and molecular epidemiology.

We describe a clonal outbreak of quinolone-resistant Haemophilus influenzae (QRHI) from an affiliated long-term care facility (LTCF-A); the outbreak was associated with the clinical use of levofloxacin, which was determined to be a risk factor for acquisition of QRHI. The minimum inhibitory concentration to which 90% of isolates were susceptible (MIC90), as determined by broth microdilution, was >4 microg/mL for levofloxacin, >2 microg/mL for moxifloxacin, >2 microg/mL for gatifloxacin, and 8 microg/mL for gemifloxacin. The MIC90, as determined by Etest (AB Biodisk), was >32 microg/mL for levofloxacin, ciprofloxacin, moxifloxacin, and gatifloxacin.

In vitro double and triple synergistic activities of Polymyxin B, imipenem, and rifampin against multidrug-resistant Acinetobacter baumannii.

Eight unrelated clinical Acinetobacter baumannii isolates resistant to all commonly used antibiotics were subjected to three-dimensional checkerboard microtiter plate dilution and time-kill studies at one-fourth of their MICs of polymyxin B, imipenem, and rifampin. Synergy was demonstrated with combinations of polymyxin B and imipenem, polymyxin B and rifampin, and polymyxin B, imipenem, and rifampin. Double combinations of polymyxin B and imipenem and of polymyxin B and rifampin were bactericidal for seven of eight isolates, and triple combinations were bactericidal for all isolates within 24 h.