j Capillary-based PCR ribotyping was used to quantify the presence/absence and relative abundance of 98 Clostridium difficile ribotypes from clinical cases of disease at health care institutions in six states of the United States. Regionally important ribotypes were identified, and institutions in close proximity did not necessarily share more ribotype diversity than institutions that were farther apart. National and international studies strongly suggest that Clostridium difficile populations are geographically distinct (1-5), meaning the composition of C. difficile genotypes varies from region to region. In the United States, there are currently few data concerning the composition, or structure, of the C. difficile population and whether health care institutions that are in close proximity are more similar with respect to ribotype diversity than those that are farther apart. The goals of this study were to quantify the abundance and diversity of C. difficile ribotypes from cases of C. difficile infection (CDI) at health care institutions in six states across the United States and to determine whether ribotype diversity was structured geographically.Stool samples from CDI-positive patients were collected from diagnostic laboratories at six health care institutions (West Roxbury, MA; York, PA; Ann Arbor, MI; St. Louis, MO; Portland, OR; and North Hollywood, CA) between 15 February 2011 and 9 September 2011 and shipped in small batches (typically 5 to 10 samples) overnight on ice to the University of Michigan for processing (Ann Arbor, MI, samples were obtained directly from the Clinical Microbiology Laboratory at the University of Michigan Health System and were not shipped). A variety of CDI diagnostic methods were represented across the institutions (Table 1), and CDI cases were defined based on center-specific diagnostic results. Institutional review board (IRB) approval was obtained as appropriate by the participating institutions. Culture was attempted for all samples submitted by each center. On three occasions, samples from three centers were unable to be processed (i.e., plated) within 24 h of receiving due to the lack of available study personnel. These samples were not included in the study. An aliquot from each sample was cultured under anaerobic conditions on prereduced taurocholate cefoxitin cycloserine fructose agar (TCCFA) plates to select for individual C. difficile colonies (6). All TCCFA plates were prepared at the University of Michigan. All samples were frozen at Ϫ80°C and recultured a second time if the first attempt at culture was unsuccessful. A single colony was analyzed from each stool sample, and the toxigenicity of isolates was inferred based on results of PCR for a C. difficile-specific region of the 16S rRNA-encoding gene (7) and tcdA (toxin A) or tcdB (toxin B) (8).The absence of tcdA or tcdB was not confirmed for all isolates (i.e., tcdA can be variably present/absent and primers may or may not amplify all tcdA/tcdB alleles), but all toxigenic isolates were positive for at least on...

The genus Methylobacterium was first proposed in 1976 (7) to accommodate gram-negative bacteria that have the ability to utilize methane and other more complex organic compounds as carbon and energy sources. Subsequently, the description of the genus Methylobacterium has been emended to include non-methane-utilizing bacteria (4); these authors also proposed that all pink-pigmented, facultatively methylotrophic bacteria be transferred to the genus Methylobactenium. This latter group of organisms includes previously named Pseudomonas rhodos, Pseudomonas rodiora, and Pseudomonas mesophilica. Nucleic acid hybridization studies verified that the pink-pigmented facultatively methylotrophic strains should not be included among the pseudomonads, and the molecular data support inclusion of these pink-pigmented bacteria in the genus Methylobactenium (12

The Microbial Identification System (MIS; Microbial ID, Inc., Newark, Del.) was evaluated for the identification of 550 clinically isolated yeasts. The organisms evaluated were fresh clinical isolates identified by methods routinely used in our laboratory (API 20C and conventional methods) and included Candida albicans (n ‫؍‬ 294), C. glabrata (n ‫؍‬ 145), C. tropicalis (n ‫؍‬ 58), C. parapsilosis (n ‫؍‬ 33), and other yeasts (n ‫؍‬ 20). In preparation for fatty acid analysis, yeasts were inoculated onto Sabouraud dextrose agar and incubated at 28؇C for 24 h. Yeasts were harvested, saponified, derivatized, and extracted, and fatty acid analysis was performed according to the manufacturer's instructions. Fatty acid profiles were analyzed, and computer identifications were made with the Yeast Clinical Library (database version 3.8). Of the 550 isolates tested, 374 (68.0%) were correctly identified to the species level, with 87 (15.8%) being incorrectly identified and 89 (16.2%) giving no identification. Repeat testing of isolates giving no identification resulted in an additional 18 isolates being correctly identified. This gave the MIS an overall identification rate of 71.3%. The most frequently misidentified yeast was C. glabrata, which was identified as Saccharomyces cerevisiae 32.4% of the time. On the basis of these results, the MIS, with its current database, does not appear suitable for the routine identification of clinically important yeasts.

The MUREX C. albicans (MC) (Murex Diagnostics), Albicans-Sure (AS) (Clinical Standards Laboratories), and BactiCard Candida (BC) (Remel) test kits were compared with the germ tube (GT) test for the rapid, presumptive identification of Candida albicans. All three test kits detect the enzymes L-proline aminopeptidase and ␤-galactosaminidase in yeast cells grown on culture media and are based on the principle that C. albicans produces both enzymes whereas other yeasts produce only one or neither of the enzymes. The organisms evaluated were fresh clinical isolates identified by methods routinely used in our laboratory (API 20C system and conventional methods) and included 303 C. albicans isolates, 153 Candida glabrata isolates, 70 Candida tropicalis isolates, 36 Candida parapsilosis isolates, 13 isolates of other Candida spp., 5 Cryptococcus neoformans isolates, and 3 Saccharomyces cerevisiae isolates. The MC, AS, BC, and GT tests detected 299 (98.7%), 300 (99.0%), 301 (99.3%), and 287 (94.7%) C. albicans isolates, respectively. There was one false-positive result with both the MC and BC kits and two false-positive results with the GT test. The enzymatic methods evaluated in this study provide rapid and accurate alternatives to the GT test for the presumptive identification of C. albicans.

Introduction: Blood cultures (BCs) frequently become contaminated during the pre-analytic phase of collection leading to downstream ramifications. We present a summary of performance improvement (PI) interventions provided by four hospital systems and common factors that contributed to decreased blood culture contamination (BCC) rates. Methods: Each hospital independently formed a multidisciplinary team and action plan for implementation of their intervention, focusing on the use of educational and training tools. Their goal was to significantly decrease their BCC rates. Pre-and post-intervention data were compared during the sustainment period to determine their success. Results: All hospitals met their goals of postintervention BCC rates and with most achieving and sustaining BCC rates B 1.0-2.0%. Conclusion: Our report highlights how four hospitals independently achieved their objective to decrease their BCC rate with the support of a multidisciplinary team. We propose a benchmark for BCC rates of 1.5 to \ 2.0% as achievable and sustainable.