Control of vancomycin-resistant enterococci in the neonatal intensive care unit.

BACKGROUND AND OBJECTIVE: Multidrug-resistant organisms (MDROs), such as vancomycin-resistant enterococci (VRE), cause serious infections, especially among high-risk patients in NICUs. When VRE was introduced and transmitted in our NICU despite recommended infection control practices, we instituted active surveillance cultures to determine their efficacy in detecting and controlling spread of VRE among high-risk infants. METHODS: Active surveillance cultures, other infection control measures, and a mandatory in-service education module on preventing MDRO transmission were implemented. Cultures were performed on NICU admission and then weekly during their stay. Molecular DNA fingerprinting of VRE isolates facilitated targeting efforts to eliminate clonal spread of VRE. Repetitive sequence PCR (rep-PCR)-based DNA fingerprinting was used to compare isolates recovered from patients with VRE infection or colonization. Environmental VRE cultures were performed around VRE-colonized or -infected patients. DNA fingerprints were prepared from the products of rep-PCR amplification and analyzed using software to determine strain genetic relatedness. RESULTS: Active surveillance cultures identified 65 patients with VRE colonization or infection among 1,820 admitted to the NICU. Rep-PCR performed on 60 VRE isolates identified 3 clusters. Cluster 1 included isolates from 21 patients and 4 isolates from the environment of the index patient. Clusters 2 and 3 included isolates from 23 and 3 patients, respectively. Similarity coefficients among the members of each cluster were 95% or greater. CONCLUSIONS: Control of transmission of multi-clonal VRE strains was achieved. Active surveillance cultures, together with implementation of other infection control measures, combined with rep-PCR DNA fingerprinting were instrumental in controlling VRE transmission in our NICU.

Cluster of Trichosporon mucoides in children associated with a faulty bronchoscope.

BACKGROUND: Several outbreaks of Pseudomonas aeruginosa infection associated with a specific model of fiberoptic bronchoscope have been reported. In a 3-week period in September 2000, we noticed an increased number of Trichosporon mucoides isolates recovered from bronchoalveolar lavage (BAL) specimens collected at our hospital. We investigated the circumstances surrounding these isolates. METHODS: Outbreak investigation was conducted, and the medical records of the affected patients were reviewed retrospectively for evidence of positive cultures for T. mucoides from BAL specimens. Specimens collected during the investigation were inoculated onto fungal culture medium and yeasts were identified with API-20C (BioMèrieux-Vitek). RESULTS: During the 3-week period BAL specimens from six patients yielded growth of T. mucoides. These six high risk patients had emergency bronchoscopy performed as a workup for pneumonia and/or respiratory distress. A Model BF XP-40 bronchoscope (Olympus) had been used in all six patients. Cultures of the bronchoscope (external body and the lumen), bronchoscope disinfector, 2% glutaraldehyde disinfecting solution and water filters/supply were performed. Only fluid from the bronchoscope lumen yielded growth of T. mucoides. Air sample cultures of the bronchoscopy suites were negative. Medical records review disclosed that affected patients were not readmitted with infection with T. mucoides and had no adverse outcomes. The bronchoscope was removed from service and returned to the manufacturer. CONCLUSION: Routine surveillance and aggressive investigation identified persistent T. mucoides contamination of one bronchoscope. The bronchoscope manufacturer later recalled the BF XP-40 model for corrective revision.

Risk of resistant infections with Enterobacteriaceae in hospitalized neonates.

OBJECTIVE: To determine the risk factors associated with progression from colonization to infection with health care-associated antimicrobial-nonsusceptible Enterobacteriaceae (ANE) in critically ill neonates. STUDY DESIGN: During a 3-year period (1998 to 2000), surveillance rectal cultures were performed on neonates admitted to our Level III neonatal intensive care unit after a cluster of four cases of ANE infection were identified in 1998. ANE were defined as members of the Enterobacteriaceae family that exhibited nonsusceptibility to ceftazidime or laboratory evidence of extended spectrum beta-lactamase (ESBL) production. RESULTS: A total of 1,710 patients were admitted to the neonatal intensive care unit during the study period. Of the 1,710 patients 300 (18%) were excluded from the risk factor analysis. Of the 1,410 remaining neonates the incidence of health care-associated ANE colonization was 17% (240 of 1,410 patients), and 14% of the colonized patients (34 of 240 patients) developed ANE infections. Of the 206 ANE-colonized patients who did not develop disease, 60 (29%) harbored ESBL-producing isolates. Of the 34 ANE-infected patients, 14 (41%) yielded growth of ESBL-producing isolates. Multiple logistic regression analysis revealed that colonized neonates with very low birth weights (<1,000 g) and those who had received prolonged exposures to antimicrobial agents were at increased risk of ANE infections. CONCLUSIONS: Colonization with ANE places hospitalized neonates at risk for development of systemic infections. Very low birth weight (<1,000 g) and prolonged exposure to antimicrobial agents were the only two independent risk factors associated with ANE infection.