Endemic Acinetobacter baumannii in a New York Hospital

Acinetobacter baumannii is an increasingly multidrug-resistant (MDR) cause of hospital-acquired infections, often associated with limited therapeutic options. We investigated A. baumannii isolates at a New York hospital to characterize genetic relatedness.Thirty A. baumannii isolates from geographically-dispersed nursing units within the hospital were studied. Isolate relatedness was assessed by repetitive sequence polymerase chain reaction (rep-PCR). The presence and characteristics of integrons were assessed by PCR. Metabolomic profiles of a subset of a prevalent strain isolates and sporadic isolates were characterized and compared.We detected a hospital-wide group of closely related carbapenem resistant MDR A. baumannii isolates. Compared with sporadic isolates, the prevalent strain isolates were more likely to be MDR (p = 0.001). Isolates from the prevalent strain carried a novel Class I integron sequence. Metabolomic profiles of selected prevalent strain isolates and sporadic isolates were similar.The A. baumannii population at our hospital represents a prevalent strain of related MDR isolates that contain a novel integron cassette. Prevalent strain and sporadic isolates did not segregate by metabolomic profiles. Further study of environmental, host, and bacterial factors associated with the persistence of prevalent endemic A. baumannii strains is needed to develop effective prevention strategies

Comparative Study of the New Colorimetric VITEK 2 Yeast Identification Card versus the Older Fluorometric Card and of CHROMagar Candida as a Source Medium with the New Card

The new VITEK 2 colorimetric card was compared to the previous fluorometric card for identification of yeast. API 20C was considered the “gold standard.” The new card consistently performed better than the older card. Isolates from CHROMagar Candida plates were identified equally as well as those from Sabouraud dextrose agar

Comparison of In Vitro Activities of Voriconazole and Five Established Antifungal Agents against Different Species of Dermatophytes Using a Broth Macrodilution Method

The in vitro activities of voriconazole against 19 different species of dermatophytes were compared with those of terbinafine, itraconazole, ketoconazole, griseofulvin, and fluconazole. MICs were determined according to a National Committee for Clinical Laboratory Standards broth macrodilution method. Voriconazole appeared more active than ketoconazole, griseofulvin, and fluconazole and less active than itraconazole and terbinafine. Based on these results, voriconazole merits further investigation as a potentially useful agent for the treatment of dermatophytosis

Multicenter Evaluation of the New VITEK 2 Advanced Colorimetric Yeast Identification Card

The performance of the new VITEK 2 Advanced Colorimetry yeast identification (YST) card for use with the VITEK 2 system (bioMérieux, Inc., Hazelwood, MO) was compared to that of the API 20C AUX (API) system (bioMérieux SA, Marcy-l'Etoile, France) in a multicenter evaluation. A total of 12 quality control, 64 challenge, and 623 clinical yeast isolates were used in the study. Comparisons of species identification, platform reliability, and substrate reproducibility were made between YST and API, with API considered the reference standard. Quality control testing to assess system and substrate reproducibility matched expected results ≥95% of the time. The YST card correctly identified 100% of the challenge strains, which covered the species range of the manufacturer's performance claims. Using clinical isolates, the YST card correctly identified 98.5%, with 1.0% of isolates incorrectly identified and 0.5% unidentified. Among clinical isolates, the YST card generated fewer low-discrimination results (18.9%) than did API (30.0%). The time to identification with YST was 18 h, compared to 48 to 72 h with API. The colorimetric YST card used with the VITEK 2 provides a highly automated, objective yeast identification method with excellent performance and reproducibility. We found this system useful for timely and accurate identification of significant yeast species in the clinical microbiology laboratory

Multiplex PCR-Ligation Detection Reaction Assay for Simultaneous Detection of Drug Resistance and Toxin Genes from Staphylococcus aureus, Enterococcus faecalis, and Enterococcus faecium▿ †

A multiplex PCR-ligation detection reaction (PCR-LDR) assay was developed for rapid detection of methicillin, tetracycline, and vancomycin resistance, as well as toxic shock toxin and Panton-Valentine leukocidin. The assay was tested on 470 positive blood culture bottles containing Staphylococcus aureus or enterococci. PCR-LDR exhibited a sensitivity and specificity of ≥98% for all components except tetracycline resistance, which had a sensitivity of 94.7%. Rapid and sensitive detection of antimicrobial resistance and virulence genes could help guide therapy and appropriate infection control measures

A Multiplex PCR/LDR Assay for the Simultaneous Identification of Category A Infectious Pathogens: Agents of Viral Hemorrhagic Fever and Variola Virus.

CDC designated category A infectious agents pose a major risk to national security and require special action for public health preparedness. They include viruses that cause viral hemorrhagic fever (VHF) syndrome as well as variola virus, the agent of smallpox. VHF is characterized by hemorrhage and fever with multi-organ failure leading to high morbidity and mortality. Smallpox, a prior scourge, has been eradicated for decades, making it a particularly serious threat if released nefariously in the essentially non-immune world population. Early detection of the causative agents, and the ability to distinguish them from other pathogens, is essential to contain outbreaks, implement proper control measures, and prevent morbidity and mortality. We have developed a multiplex detection assay that uses several species-specific PCR primers to generate amplicons from multiple pathogens; these are then targeted in a ligase detection reaction (LDR). The resultant fluorescently-labeled ligation products are detected on a universal array enabling simultaneous identification of the pathogens. The assay was evaluated on 32 different isolates associated with VHF (ebolavirus, marburgvirus, Crimean Congo hemorrhagic fever virus, Lassa fever virus, Rift Valley fever virus, Dengue virus, and Yellow fever virus) as well as variola virus and vaccinia virus (the agent of smallpox and its vaccine strain, respectively). The assay was able to detect all viruses tested, including 8 sequences representative of different variola virus strains from the CDC repository. It does not cross react with other emerging zoonoses such as monkeypox virus or cowpox virus, or six flaviviruses tested (St. Louis encephalitis virus, Murray Valley encephalitis virus, Powassan virus, Tick-borne encephalitis virus, West Nile virus and Japanese encephalitis virus)