Karen C Carroll

Publications of Karen C Carroll

• Caveat emptor: the role of suboptimal bronchoscope repair practices by a third-party vendor in a pseudo-outbreak of pseudomonas in bronchoalveolar lavage specimens.

  Authors: Sara E Cosgrove, Polly Ristaino, Anne Caston-Gaa, Donna P Fellerman, Elaine F Nowakowski, Karen C Carroll, Trish M Perl, Lisa L Maragakis

  Infection control and hospital epidemiology : the official journal of the Society of Hospital Epidemiologists of America. 03/2012; 33(3):224-9.

  To describe a pseudo-outbreak associated with loose bronchoscope biopsy ports caused by inadequate bronchoscope repair practices by third-party vendors and to alert healthcare personnel to assessTo describe a pseudo-outbreak associated with loose bronchoscope biopsy ports caused by inadequate bronchoscope repair practices by third-party vendors and to alert healthcare personnel to assess bronchoscope repair practices. Outbreak investigation. A 925-bed tertiary care hospital in Baltimore, Maryland. PatIENTS: Patients who underwent bronchoscopy with certain bronchoscopes after they had been repaired by a third-party vendor. An epidemiologic investigation was conducted to determine the cause of Pseudomonas putida growth in 4 bronchoalveolar lavage (BAL) specimens within a 3-day period in May 2008. All bronchoscopes were inspected, and cultures were obtained from bronchoscopes and the environment. Bronchoscope cleaning and maintenance practices were reviewed. Microbiologic results from BAL specimens and medical records were reviewed to find additional cases. All 4 case patients had undergone bronchoscopy with one of 2 bronchoscopes, both of which had loose biopsy ports. Bronchoscope cultures grew P. putida, Pseudomonas aeruginosa, and Stenotrophomonas. The P. putida strains from the bronchoscopes matched those from the patients. Specimens from 12 additional patients who underwent bronchoscopy with these bronchoscopes grew P. putida, P. aeruginosa, or Stenotrophomonas. No patients developed clinical signs or symptoms of infection, but 7 were treated with antibiotics. Investigation revealed that the implicated bronchoscopes had been sent to an external vendor for repair; examination by the manufacturer revealed irregularities in repairs and nonstandard part replacements. Third-party vendors without access to proprietary information may contribute to mechanical malfunction of medical devices, which can lead to contamination and incomplete disinfection.

• Antimicrobial prescribing practices in response to different Clostridium difficile diagnostic methodologies.

  Authors: Emily R M Sydnor, Abigail Lenhart, Brandon Trollinger, Edina Avdic, Lisa L Maragakis, Karen C Carroll, Sara E Cosgrove

  Infection control and hospital epidemiology : the official journal of the Society of Hospital Epidemiologists of America. 11/2011; 32(11):1133-6.

  We evaluated treatment decisions and antimicrobial use related to 2 testing algorithms for Clostridium difficile infection (CDI). Our findings suggest that a 2-step testing algorithm using rapidWe evaluated treatment decisions and antimicrobial use related to 2 testing algorithms for Clostridium difficile infection (CDI). Our findings suggest that a 2-step testing algorithm using rapid polymerase chain reaction confirmatory testing leads to decreased unnecessary anti-CDI antimicrobial use. In addition, a significant proportion of patients with confirmed CDI were not treated according to recommended guidelines.

• First NDM-positive Salmonella sp. strain identified in the United States.

  Authors: Patrice Savard, Ramya Gopinath, Wenming Zhu, Brandon Kitchel, J Kamile Rasheed, Tsigereda Tekle, Ava Roberts, Tracy Ross, Jafar Razeq, B Mark Landrum, Lucy E Wilson, Brandi Limbago, Trish M Perl, Karen C Carroll

  Antimicrobial agents and chemotherapy. 10/2011; 55(12):5957-8.

  Antimicrobial resistance among Enterobacteriaceae is growing, largely due to β-lactamase production.…

• Methicillin-resistant Staphylococcus aureus colonization and risk of subsequent infection in critically ill children: importance of preventing nosocomial methicillin-resistant Staphylococcus aureus transmission.

  Authors: Aaron M Milstone, Brian W Goldner, Tracy Ross, John W Shepard, Karen C Carroll, Trish M Perl

  Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. 08/2011; 53(9):853-9.

  Methicillin-resistant Staphylococcus aureus (MRSA) colonization is a predictor of subsequent infection in hospitalized adults. The risk of subsequent MRSA infections in hospitalized childrenMethicillin-resistant Staphylococcus aureus (MRSA) colonization is a predictor of subsequent infection in hospitalized adults. The risk of subsequent MRSA infections in hospitalized children colonized with MRSA is unknown. Children admitted to an academic medical center's pediatric intensive care unit between March 2007 and March 2010 were included in the study. Anterior naris swabs were cultured to identify children with MRSA colonization at admission. Laboratory databases were queried and National Healthcare Safety Network definitions applied to identify patients with MRSA infections during their hospitalization or after discharge. The MRSA admission prevalence among 3140 children was 4.9%. Overall, 56 children (1.8%) developed an MRSA infection, including 13 (8.5%) colonized on admission and 43 (1.4%) not colonized on admission (relative risk [RR], 5.9; 95% confidence interval [CI], 3.4-10.1). Of those, 10 children (0.3%) developed an MRSA infection during their hospitalization, including 3 of 153 children (1.9%) colonized on admission and 7 of 2987 children (0.2%) not colonized on admission (RR, 8.4; 95% CI, 2.7-25.8). African-Americans and those with public health insurance were more likely to get a subsequent infection (P < .01 and P = .03, respectively). We found that 15 children acquired MRSA colonization in the pediatric intensive care unit, and 7 (47%) developed a subsequent MRSA infection. MRSA colonization is a risk factor for subsequent MRSA infection in children. Although MRSA colonized children may have lower risks of subsequent infection than adults, children who acquire MRSA in the hospital have similarly high rates of infection. Preventing transmission of MRSA in hospitalized children should remain a priority.

• Risk factors for positive admission surveillance cultures for methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci in a neurocritical care unit.

  Authors: Paras Minhas, Trish M Perl, Karen C Carroll, John W Shepard, K Alexander Shangraw, Donna Fellerman, Wendy C Ziai

  Critical care medicine. 06/2011; 39(10):2322-9.

  Hospitals are under increasing pressure to perform active surveillance cultures for methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus. This study aimed to identifyHospitals are under increasing pressure to perform active surveillance cultures for methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus. This study aimed to identify patients at low and high risk for positive admission surveillance cultures for methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus in a neurocritical care unit using readily ascertainable historical factors. Before/after study with nested case/control study. Neurocritical care unit of an academic hospital. During the intervention period (July 2007 to June 2008), after implementation of an admission surveillance culture screening program for methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus, 2,059 patients were admitted to the neurocritical care unit for a total of 5,957 patient days. Cases had positive methicillin-resistant Staphylococcus aureus or vancomycin-resistant Enterococcus admission surveillance cultures within 48 hrs of hospital admission. Controls had negative cultures. Admission surveillance cultures grew methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus in 35 of 823 (4.3%) and 19 of 766 (2.5%) patients, respectively. Factors significantly associated with both methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus colonization were intravenous antibiotics and hospitalization in the past year, immunocompromised health status, intravenous drug use, long-term hemodialysis, and known prior carrier status. Transfer from an outside hospital and residence in a long-term care facility in the past year were associated with vancomycin-resistant Enterococcus colonization. Classification and regression tree analysis was used to identify variables that best predicted positive methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus surveillance cultures. A classification and regression tree model with six of these variables yielded an overall cross-validated predictive accuracy of 87.12% to detect methicillin-resistant Staphylococcus aureus colonization. For vancomycin-resistant Enterococcus, a four-variable classification and regression tree model (intravenous antibiotics, hospitalization and long-term patient care in the past year, and not being "admitted same day of procedure") optimized the predictive accuracy (94.91%). There were no cases of vancomycin-resistant Enterococcus colonization in patients admitted same day of procedure. Colonization with methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus in neurocritical care patients can be predicted with a high predictive accuracy using decision trees that include four to six readily attainable risk factors. In our setting, in the absence of these risk factors and in patients admitted from home for neurosurgical procedures, routine admission surveillance cultures to the intensive care unit may not be cost-effective.

• Biology of Clostridium difficile: implications for epidemiology and diagnosis.

  Authors: Carroll Karen C, Bartlett John G

  Annual review of microbiology. 06/2011; 65:501-21.

  Clostridium difficile is an anaerobic, spore-forming, gram-positive rod that causes a spectrum of antibiotic-associated colitis through the elaboration of two large clostridial toxins and otherClostridium difficile is an anaerobic, spore-forming, gram-positive rod that causes a spectrum of antibiotic-associated colitis through the elaboration of two large clostridial toxins and other virulence factors. Since its discovery in 1978 as the agent responsible for pseudomembranous colitis, the organism has continued to evolve into an adaptable, aggressive, hypervirulent strain. Advances in molecular methods and improved animal models have facilitated an understanding of how this organism survives in the environment, adapts to the gastrointestinal tract of animals and humans, and accomplishes its unique pathogenesis. The advances in microbiology have been accompanied by some important clinical observations including increased rates of C. difficile infection, increased virulence, and multiple outbreaks. The major new risk is fluoroquinolone use; there is also an association with proton pump inhibitors and increased recognition of cases in outpatients, pediatric patients, and patients without recent antibiotic use. The combination of more aggressive strains with mobile genomes in a setting of an expanded pool of individuals at risk has refocused attention on and challenged assumptions regarding diagnostic gold standards. Future research is likely to build upon the advancements in phylogenetics to create novel strategies for diagnosis, treatment, and prevention.

• Tests for the diagnosis of Clostridium difficile infection: the next generation.

  Authors: Karen C Carroll

  Anaerobe. 03/2011; 17(4):170-4.

  Clostridium difficile (C. difficile) causes 25-30% of cases of antibiotic associated diarrhea and most cases of pseudomembranous colitis. Patients presenting with diarrhea after hospitalization for 3Clostridium difficile (C. difficile) causes 25-30% of cases of antibiotic associated diarrhea and most cases of pseudomembranous colitis. Patients presenting with diarrhea after hospitalization for 3 or more days should be tested for C. difficile. There are many options available for testing, each of which has inherent advantages and disadvantages. Most laboratories perform toxin testing using an enzyme immunoassay method. In general these tests have sensitivities ranging from 60 to 70% and specificities of 98%. When using these methods, symptomatic patients with negative tests should be tested by another more sensitive method. Until recently, cell culture cytotoxicity neutralization assays (CCNAs) were considered the gold standard in the U.S. A two-step algorithm using an EIA for glutamate dehydrogenase detection followed by testing positives using CCNA, offered an improved alternative until the availability of molecular assays. Although early studies that compared the GDH assay to CCNA demonstrated high sensitivity and negative predictive values, more recent comparisons to toxigenic culture and PCR have shown the sensitivity to be in the mid to high 80's. When testing using a sensitive assay, repeat testing is not cost-effective. Outbreaks caused by a toxin variant epidemic strain have renewed interest in bacterial culture. Toxigenic culture has emerged as the new gold standard against which newer assays should be compared. However, there is no agreed upon standard method for culture performance. At least 4 FDA cleared nucleic acid amplification assays are available to clinical laboratories and several of these have been well evaluated in the literature. Because these assays detect a gene that encodes toxin and not the toxin itself it is important that laboratories test only patients with diarrhea. These molecular assays have been shown to be superior to toxin EIAs, CCNA and 2-step algorithms, but not to toxigenic culture. More studies are needed to assess the impact of molecular tests on treatment and nosocomial spread of Clostridium difficile infections.

• Genotypic and phenotypic characterization of methicillin-susceptible Staphylococcus aureus isolates misidentified as methicillin-resistant Staphylococcus aureus by the BD GeneOhm MRSA assay.

  Authors: Paul D Stamper, Lisa Louie, Henry Wong, Andrew E Simor, Jason E Farley, Karen C Carroll

  Journal of clinical microbiology. 02/2011; 49(4):1240-4.

  Twenty-three nasal swab samples that tested positive for methicillin-resistant Staphylococcus aureus (MRSA) on initial testing by the BD GeneOhm MRSA assay (BD-MRSA PCR; BD GeneOhm, San Diego, CA)Twenty-three nasal swab samples that tested positive for methicillin-resistant Staphylococcus aureus (MRSA) on initial testing by the BD GeneOhm MRSA assay (BD-MRSA PCR; BD GeneOhm, San Diego, CA) were culture positive only for methicillin-susceptible S. aureus (MSSA) from an enrichment broth. The 23 recovered isolates were confirmed as MSSA by a variety of phenotypic methods, including the BD Phoenix automated microbiology system (BD Diagnostics, Sparks, MD), oxacillin screening agar (BD Diagnostics), BBL CHROMagar MRSA (BD Diagnostics), and a PBP2' assay (Denka Seiken Co., Tokyo, Japan); susceptibilities were determined by using Mueller-Hinton agar with oxacillin. All were positive by nuc PCR, specific for S. aureus, but negative for mecA with one exception. Isolates were characterized by using multiplex PCR methodology to determine structural types and variants (SCCmec typing); additional PCRs were performed for the detection of the ccr and mec complexes, the junkyard regions as well as the Panton-Valentine leukocidin. Pulsed-field gel electrophoresis was used to determine clonality. One phenotypic MSSA isolate contained an intact SCCmec. Twelve MSSA isolates tested positive for MRSA by the BD-MRSA PCR because of amplification of the mec priming site flanking the SCC insertion point, although these isolates lacked mecA. The 10 remaining isolates were not MRSA and tested as MSSA by phenotypic and genotypic assays. In our patient population, diagnostic and surveillance testing and subsequent infection control practices may be impacted by the frequency of these excision events when using the BD-MRSA PCR for MRSA detection.

• Comparison of BD Bactec Plus Aerobic/F medium to VersaTREK Redox 1 blood culture medium for detection of Candida spp. in seeded blood culture specimens containing therapeutic levels of antifungal agents.

  Authors: Stefan Riedel, Stephen W Eisinger, Lisa Dam, Paul D Stamper, Karen C Carroll

  Journal of clinical microbiology. 01/2011; 49(4):1524-9.

  Recovery of Candida spp. using the BD Bactec FX blood culture (BC) system (Bactec Plus Aerobic/F medium) and the VersaTREK system (aerobic Redox medium) was evaluated using seeded BC bottles with andRecovery of Candida spp. using the BD Bactec FX blood culture (BC) system (Bactec Plus Aerobic/F medium) and the VersaTREK system (aerobic Redox medium) was evaluated using seeded BC bottles with and without the addition of commonly used antifungal agents. BC bottles (n = 1,442) were each inoculated with 10 ml human whole blood and 0.1 ml of suspensions of Candida spp., with or without antifungal agents. BC bottles were incubated in the corresponding system for a maximum of 5 days. In the absence of antifungal agents, Bactec FX recovered 97.4% of Candida spp., and VersaTREK recovered 99.1% (P = 0.154). With regard to length of time to detection (LTD) and overall recovery, both systems had various levels of effectiveness in recovering C. glabrata. In bottles containing antifungal agents, Bactec FX recovered 83.1% of isolates, whereas VersaTREK recovered 50.7% of Candida spp. (P < 0.001). For BC bottles without the addition of antifungal agents, the median LTD for VersaTREK was 2.2 h faster than that of Bactec FX (P < 0.001). In the presence of antifungal agents, the Bactec FX recovery time was significantly faster than that of VersaTREK (median difference of 10.8 h, P < 0.001). We conclude that both systems have comparable abilities to recover Candida spp. from seeded blood cultures in the absence of antifungal agents. In the presence of therapeutic levels of commonly used antifungal agents, the Bactec FX system demonstrated a significantly greater recovery of various Candida spp., as well as a shorter LTD.

• Role of the clinical mycobacteriology laboratory in diagnosis and management of tuberculosis in low-prevalence settings.

  Authors: Nicole M Parrish, Karen C Carroll

  Journal of clinical microbiology. 12/2010; 49(3):772-6.

  Tuberculosis (TB) remains a global epidemic, despite a significant decline in reported cases in the United States between 2008 and 2009. While the exact nature of this decline is unclear, one thingTuberculosis (TB) remains a global epidemic, despite a significant decline in reported cases in the United States between 2008 and 2009. While the exact nature of this decline is unclear, one thing remains certain: TB, including multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB, is no longer restricted to developing regions of the globe. It is of vital importance that both public and private mycobacteriology laboratories maintain the ability to detect and identify Mycobacterium tuberculosis from patient specimens, as well as correctly determine the presence of antibiotic resistance. To do this effectively requires careful attention to preanalytical, analytical, and postanalytical aspects of testing. Respiratory specimens require digestion and concentration followed by fluorescence microscopy. The Centers for Disease Control and Prevention (CDC) recommends the performance of a direct nucleic acid amplification method, regardless of smear results, on specimens from patients in whom the suspicion of tuberculosis is high. Liquid-based technologies are more rapid and sensitive for the detection of M. tuberculosis in culture and nucleic acid probes, but biochemicals are preferred for identification once growth is detected. Susceptibility testing is most often done using either the agar proportion method or a commercial broth system. New genotypic and phenotypic methods of susceptibility testing include first- and second-line agents and are promising, though not yet widely available. Finally, gamma interferon release assays are preferred to the tuberculin skin test for screening certain at-risk populations, and new CDC guidelines are available that assist clinicians in their use.

• Evaluation of BBL CHROMagar VanRE for detection of vancomycin-resistant Enterococci in rectal swab specimens.

  Authors: Paul D Stamper, Stephanie Shulder, Pearl Bekalo, Deepika Manandhar, Tracy L Ross, Sharon Speser, Julie Kingery, Karen C Carroll

  Journal of clinical microbiology. 11/2010; 48(11):4294-7.

  A study was performed on 517 surveillance rectal swabs to evaluate a selective and differential chromogenic medium, the BBL CHROMagar VanRE (CVRE), which enables recovery and identification of VanA-A study was performed on 517 surveillance rectal swabs to evaluate a selective and differential chromogenic medium, the BBL CHROMagar VanRE (CVRE), which enables recovery and identification of VanA- and VanB-containing Enterococcus faecium (ENFM) and Enterococcus faecalis (ENFS) isolates. Compared to BBL Enterococcosel agar, a bile-esculin-azide-vancomycin (BEAV) agar, the initial overall sensitivity, specificity, and positive and negative predictive values of CVRE for the detection of vancomycin-resistant ENFM and ENFS were 99.1% and 94.8% and 84.2% and 99.7%, respectively. Among our patient population, more vancomycin-resistant enterococci (VRE) were recovered with CVRE than BEAV.

• Blood cultures: key elements for best practices and future directions.

  Authors: Stefan Riedel, Karen C Carroll

  Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy. 10/2010; 16(5):301-16.

  Bloodstream infections (BSI) cause significant morbidity and mortality among populations worldwide. Blood cultures (BCs) are regarded as the "gold standard" for diagnosis of bacteremia and are amongBloodstream infections (BSI) cause significant morbidity and mortality among populations worldwide. Blood cultures (BCs) are regarded as the "gold standard" for diagnosis of bacteremia and are among the most important functions of the clinical microbiology laboratory. Significant changes in the methods and techniques of obtaining BCs have occurred since the first inception of BCs into clinical practice. Aside from significant improvements of established, conventional technology, new assays for diagnosis of bacteremia and fungemia, particularly those involving molecular techniques, are now available. BCs must be collected under sterile conditions and guidelines for appropriate collection, processing, and results reporting of BCs have been established. This review provides comprehensive information on optimal BC practices for laboratories, utilizing traditional approaches and emerging technology. As laboratories and clinicians must appreciate the key factors affecting the use of these techniques, improved communication between laboratory personnel and clinicians regarding such elements as duration of incubation, workup of contaminants and critical action value reporting will greatly improve the diagnostic approach to BSI.

• Rapid identification of bacterial pathogens in positive blood culture bottles by use of a broad-based PCR assay coupled with high-resolution melt analysis.

  Authors: Helen Won, Richard Rothman, Padmini Ramachandran, Yu-Hsiang Hsieh, Aleksandar Kecojevic, Karen C Carroll, Deborah Aird, Charlotte Gaydos, Samuel Yang

  Journal of clinical microbiology. 09/2010; 48(9):3410-3.

  We evaluated a broad-based PCR assay coupled with high-resolution melt analysis for rapid bacterial identification in patients with bacterial sepsis. With a reference library of 60 clinicallyWe evaluated a broad-based PCR assay coupled with high-resolution melt analysis for rapid bacterial identification in patients with bacterial sepsis. With a reference library of 60 clinically relevant bacterial species, 52 positive blood culture samples were tested. Our assay identified 46/52 samples at the species level, with 100% concordance to culture findings.

• Low frequency of environmental contamination with methicillin-resistant Staphylococcus aureus in an inner city emergency department and a human immunodeficiency virus outpatient clinic.

  Authors: Jonathan A Otter, Catherine L Passaretti, Gary L French, Tracy Ross, Karen C Carroll, Trish M Perl

  American journal of infection control. 09/2010; 39(2):151-3.

  We investigated methicillin-resistant Staphylococcus aureus (MRSA) environmental contamination in an inner city outpatient clinic and emergency department (ED). Moistened cotton-tipped swabs wereWe investigated methicillin-resistant Staphylococcus aureus (MRSA) environmental contamination in an inner city outpatient clinic and emergency department (ED). Moistened cotton-tipped swabs were used to sample 63 surfaces in the outpatient clinic and 69 surfaces in the ED. MRSA was identified on none of the 63 surfaces in the outpatient clinic and on 7% of the 69 surfaces in the ED. Our findings may have implications for cleaning and disinfection regimens in outpatient settings.

• Evaluation of Bio-Rad MRSASelect agar for detection of methicillin-resistant Staphylococcus aureus directly from blood cultures.

  Authors: Stefan Riedel, Lisa Dam, Paul D Stamper, Syed A R Shah, Karen C Carroll

  Journal of clinical microbiology. 06/2010; 48(6):2285-8.

  MRSASelect agar (Bio-Rad, Redmond, WA) was evaluated for its performance in detecting MRSA directly from positive blood cultures containing Gram-positive cocci in clusters. Agar plates were evaluatedMRSASelect agar (Bio-Rad, Redmond, WA) was evaluated for its performance in detecting MRSA directly from positive blood cultures containing Gram-positive cocci in clusters. Agar plates were evaluated for the presence of pink colonies at 18 to 24 h. Results were compared to organism identification by using standard laboratory methods. Confirming coagulase on pink isolates, the sensitivity and specificity were both 99%.

• Community-associated methicillin-resistant Staphylococcus aureus strains in pediatric intensive care unit.

  Authors: Aaron M Milstone, Karen C Carroll, Tracy Ross, K Alexander Shangraw, Trish M Perl

  Emerging infectious diseases. 04/2010; 16(4):647-55.

  Virulent community-associated methicillin-resistant Staphylococcus-aureus (CA-MRSA) strains have spread rapidly in the United States. To characterize the degree to which CA-MRSA strains are importedVirulent community-associated methicillin-resistant Staphylococcus-aureus (CA-MRSA) strains have spread rapidly in the United States. To characterize the degree to which CA-MRSA strains are imported into and transmitted in pediatric intensive care units (PICU), we performed a retrospective study of children admitted to The Johns Hopkins Hospital PICU, March 1, 2007-May 31, 2008. We found that 72 (6%) of 1,674 PICU patients were colonized with MRSA. MRSA-colonized patients were more likely to be younger (median age 3 years vs. 5 years; p = 0.02) and African American (p<0.001) and to have been hospitalized within 12 months (p<0.001) than were noncolonized patients. MRSA isolates from 66 (92%) colonized patients were fingerprinted; 40 (61%) were genotypically CA-MRSA strains. CA-MRSA strains were isolated from 50% of patients who became colonized with MRSA and caused the only hospital-acquired MRSA catheter-associated bloodstream infection in the cohort. Epidemic CA-MRSA strains are becoming endemic to PICUs, can be transmitted to hospitalized children, and can cause invasive hospital-acquired infections. Further appraisal of MRSA control is needed.

• Role of decolonization in a comprehensive strategy to reduce methicillin-resistant Staphylococcus aureus infections in the neonatal intensive care unit: an observational cohort study.

  Authors: Aaron M Milstone, Alicia Budd, John W Shepard, Tracy Ross, Susan Aucott, Karen C Carroll, Trish M Perl

  Infection control and hospital epidemiology : the official journal of the Society of Hospital Epidemiologists of America. 03/2010; 31(5):558-60.

• Fatal infection caused by Cupriavidus gilardii in a child with aplastic anemia.

  Authors: Matthew Karafin, Mark Romagnoli, Doran L Fink, Tracy Howard, Rachel Rau, Aaron M Milstone, Karen C Carroll

  Journal of clinical microbiology. 03/2010; 48(3):1005-7.

  Cupriavidus gilardii is a Gram-negative bacterium that has rarely been associated with human infections. We report a fatal case of sepsis caused by C. gilardii in a previously healthy 12-year-oldCupriavidus gilardii is a Gram-negative bacterium that has rarely been associated with human infections. We report a fatal case of sepsis caused by C. gilardii in a previously healthy 12-year-old female.

• Comparison of Two Rapid Assays for Clostridium difficile Common Antigen and a C difficile Toxin A/B Assay With the Cell Culture Neutralization Assay.

  Authors: Megan E Reller, Romina C Alcabasa, Clara A Lema, Karen C Carroll

  American journal of clinical pathology. 01/2010; 133(1):107-109.

  We compared 3 rapid assays for Clostridium difficile with a cell culture cytotoxicity neutralization assay (CCNA). Of 600 stool samples, 46 were positive for toxigenic C difficile. Both rapid commonWe compared 3 rapid assays for Clostridium difficile with a cell culture cytotoxicity neutralization assay (CCNA). Of 600 stool samples, 46 were positive for toxigenic C difficile. Both rapid common antigen assays were highly sensitive (91.3%-100%) and, therefore, were appropriate screening tests. The rapid toxin assay had poor sensitivity (61%) but excellent specificity (99.3%). Testing stools for glutamate dehydrogenase (step 1) and those positive with a rapid toxin assay (step 2) would correctly classify 81% of submitted specimens within 2 hours, including during periods of limited staffing (evenings, nights, and weekends). CCNA could then be used as a third step to test rapid toxin-negative samples, thereby providing a final result for the remaining 19% of samples by 48 to 72 hours. The use of rapid assays as outlined could enhance timely diagnosis of C difficile.

• C. Diff Quik Chek Complete EIA Provides a Reliable First-Line Method for Detection of Clostridium difficile in Stool Specimens.

  Authors: Criziel D. Quinn, Susan E Sefers, Wisal Babiker, Ying He, Romina Alcabasa, Charles W Stratton, Karen C Carroll, Yi-Wei Tang

  Journal of clinical microbiology. 12/2009;

  We evaluated a single membrane device assay to simultaneously detect both Clostridium difficile glutamate dehydrogenase (GDH) and toxins A/B antigens against a standard that combines two PCR assaysWe evaluated a single membrane device assay to simultaneously detect both Clostridium difficile glutamate dehydrogenase (GDH) and toxins A/B antigens against a standard that combines two PCR assays and cytotoxigenic culture. Results with dual GDH and toxins A/B antigen positives and negatives can be reported immediately as true positives and negatives, respectively. Specimens with discrepant results between GDH and toxins A/B, which comprised 13.2% of specimens, need to be re-tested.