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Amit S Chitnis,
Pam S Caruthers,
Agam K Rao,
Joanne Lamb,
Robert Lurvey,
Valery Beau De Rochars,
Brandon Kitchel,
Margarita Cancio,
Thomas J Török,
Alice Y Guh,
Carolyn V Gould,
Matthew E Wise
[show abstract]
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ABSTRACT: Objective. To describe a Klebsiella pneumoniae carbapenemase (KPC)-producing carbapenem-resistant Enterobacteriaceae (CRE) outbreak and interventions to prevent transmission. Design, setting, and patients. Epidemiologic investigation of a CRE outbreak among patients at a long-term acute care hospital (LTACH). Methods. Microbiology records at LTACH A from March 2009 through February 2011 were reviewed to identify CRE transmission cases and cases admitted with CRE. CRE bacteremia episodes were identified during March 2009-July 2011. Biweekly CRE prevalence surveys were conducted during July 2010-July 2011, and interventions to prevent transmission were implemented, including education and auditing of staff and isolation and cohorting of CRE patients with dedicated nursing staff and shared medical equipment. Trends were evaluated using weighted linear or Poisson regression. CRE transmission cases were included in a case-control study to evaluate risk factors for acquisition. A real-time polymerase chain reaction assay was used to detect the bla(KPC) gene, and pulsed-field gel electrophoresis was performed to assess the genetic relatedness of isolates. Results. Ninety-nine CRE transmission cases, 16 admission cases (from 7 acute care hospitals), and 29 CRE bacteremia episodes were identified. Significant reductions were observed in CRE prevalence (49% vs 8%), percentage of patients screened with newly detected CRE (44% vs 0%), and CRE bacteremia episodes (2.5 vs 0.0 per 1,000 patient-days). Cases were more likely to have received β-lactams, have diabetes, and require mechanical ventilation. All tested isolates were KPC-producing K. pneumoniae, and nearly all isolates were genetically related. Conclusion. CRE transmission can be reduced in LTACHs through surveillance testing and targeted interventions. Sustainable reductions within and across healthcare facilities may require a regional public health approach.
Infection Control and Hospital Epidemiology 10/2012; 33(10):984-92. · 3.67 Impact Factor
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Amit S Chitnis,
Alice Y Guh,
Isaac Benowitz,
Velusamy Srinivasan,
Robert E Gertz,
Patricia L Shewmaker,
Bernard W Beall,
Heather O'Connell,
Judith Noble-Wang,
Matthew F Gornet,
Chris Van Beneden,
Sarah L Patrick,
George Turabelidze,
Priti R Patel
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ABSTRACT: To investigate an outbreak of bacterial meningitis at an outpatient radiology clinic (clinic A) and to determine the source and implement measures to prevent additional infections.
A case was defined as bacterial meningitis in a patient undergoing myelography at clinic A from October 11 to 25, 2010. Patients who underwent myelography and other procedures at clinic A during that period were interviewed, medical records were reviewed, and infection prevention practices were assessed. Case-patient cerebrospinal fluid (CSF) specimens, oral specimens from health care personnel (HCP), and opened iohexol vials were tested for bacteria. Bacterial isolates were compared using pulsed-field gel electrophoresis. A culture-negative CSF specimen was tested using a real-time polymerase chain reaction assay.
Three cases were identified among 35 clinic A patients who underwent procedures from October 11 to 25, 2010. All case-patients required hospitalization, 2 in an intensive care unit. Case-patients had myelography performed by the same radiology physician assistant and technician on October 25; all patients who underwent myelography on October 25 were affected. HCP did not wear facemasks and reused single-dose iohexol vials for multiple patients. Streptococcus salivarius (a bacteria commonly found in oral flora) was detected in the CSF of 2 case-patients (1 by culture, 1 using real-time polymerase chain reaction) and in HCP oral specimens; 1 opened iohexol vial contained Staphylococcus epidermidis. Pulsed-field gel electrophoresis profiles from the case-patient S salivarius and the radiology physician assistant were indistinguishable.
Bacterial meningitis likely occurred because HCP performing myelography did not wear facemasks; lapses in injection practices may have contributed to transmission. Targeted education regarding mask use and safe injection practices is needed among radiology HCP.
Journal of the American College of Radiology: JACR 03/2012; 9(3):185-90.
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Velusamy Srinivasan,
Robert E Gertz,
Patricia L Shewmaker,
Sarah Patrick, Amit S Chitnis,
Heather O'Connell,
Isaac Benowitz,
Priti Patel,
Alice Y Guh,
Judith Noble-Wang,
George Turabelidze,
Bernard Beall
[show abstract]
[hide abstract]
ABSTRACT: We recently investigated three cases of bacterial meningitis that were reported from a midwestern radiology clinic where facemasks were not worn during spinal injection of contrast agent during myelography procedures. Using pulsed field gel electrophoresis we linked a case strain of S. salivarius to an oral specimen of a radiology physician assistant (RPA). We also used a real-time PCR assay to detect S. salivarius DNA within a culture-negative cerebrospinal fluid (CSF) specimen. Here we extend this investigation through using a nested PCR/sequencing strategy to link the culture-negative CSF specimen to the case strain. We also provide validation of the real-time PCR assay used, demonstrating that it is not solely specific for Streptococcus salivarius, but is also highly sensitive for detection of the closely related oral species Streptococcus vestibularis. Through using multilocus sequence typing and 16S rDNA sequencing we further strengthen the link between the CSF case isolate and the RPA carriage isolate. We also demonstrate that the newly characterized strains from this study are distinct from previously characterized S. salivarius strains associated with carriage and meningitis.
PLoS ONE 01/2012; 7(2):e32169. · 4.09 Impact Factor
