Morgan A. Pence

Diagnostic Assays for Identification of Microorganisms and Antimicrobial Resistance Determinants Directly from Positive Blood Culture Broth

The detection of blood stream infections is one of the most important functions of the clinical microbiology laboratory. Sepsis is a clinical emergency, and mortality increases if commencement of appropriate antimicrobial therapy is delayed. Automated blood culture systems are the most sensitive approach for detection of the causative agent of sepsis. Several laboratory methods have been developed to expedite identification of organisms directly from positive blood culture broth. The principle and analytical performance characteristics of these methods are described in this review.

Two Cases of Kerstersia gyiorum Isolated from Sites of Chronic Infection

ABSTRACT Kerstersia gyiorum is infrequently associated with human infection. We report the isolation of Kerstersia gyiorum from two patients: the first, a patient with chronic ear infections, and the second, a patient with a chronic leg wound. Both isolates were resistant to ciprofloxacin, which has not been previously reported.

Pulmonary Phaeohyphomycosis Caused by Phaeoacremonium in a Kidney Transplant Recipient: Successful Treatment with Posaconazole

We report a rare case of pulmonary phaeohyphomycosis in a 49-year-old woman 6 years after kidney transplantation. She presented with dyspnea, cough, and fatigue. Her chest CT scan revealed nodular opacities in the right upper lung. A fine needle aspirate biopsy culture yielded Phaeoacremonium and surgical pathology of the biopsy showed chronic inflammation. We successfully treated her with posaconazole and managed drug interactions between posaconazole and tacrolimus. This is the second reported case of biopsy-proven pulmonary infection by Phaeoacremonium in a kidney transplant recipient and successfully treated with posaconazole.

Comparison of Chromogenic Media for Recovery of Carbapenemase-Producing Enterobacteriaceae (CPE) and Evaluation of CPE Prevalence at a Tertiary Care Academic Medical Center

ABSTRACT We evaluated the performance characteristics of chromID CARBA and HardyCHROM Carbapenemase for the detection of carbapenemase-producing Enterobacteriaceae (CPE). A CPE prevalence study was conducted using chromID CARBA; this demonstrated that in low-prevalence settings, CPE screening agars may lack specificity, and confirmation of putative isolates is necessary.

The Brief Case: Wound Infection with Plesiomonas shigelloides following a Freshwater Injury

An 11-year-old, previously healthy boy in north Texas was riding his bicycle along a pond when his bicycle tire became stuck in the mud. The patient fell off his bike into the pond and struck his right knee on a hard object, acquiring a 2-cm-long horseshoe-shaped laceration. The patients mother

The Brief Case: Dyspnea in a Profoundly Immunocompromised Man

A 61-year-old male presented to a hospital in Missouri with several months of progressive shortness of breath and low-grade fevers. He had a past medical history of chronic obstructive pulmonary disease and diffuse large B-cell lymphoma, which was treated with a matched unrelated donor bone marrow

Evaluation of the illumigene Mycoplasma Direct DNA Amplification Assay

ABSTRACT Mycoplasma pneumoniae is a common cause of community-acquired pneumonia. The illumigene Mycoplasma Direct (iMD) DNA amplification assay is a qualitative in vitro test utilizing loop-mediated isothermal amplification (LAMP) technology for the direct detection of M. pneumoniae DNA in respiratory specimens. The iMD assay does not require the preextraction of nucleic acids from specimens, which is a prerequisite step for the previously approved illumigene Mycoplasma (iM) assay. The aim of this prospective multicenter study was to evaluate the performance characteristics of the newly developed iMD assay, compared with the iM assay. Subjects with symptoms of upper respiratory illnesses suggesting M. pneumoniae infection were enrolled at three sites in the United States. Respiratory specimens were obtained using dual throat swabs. One swab was tested with the iMD assay at each enrollment site. Reference testing with the iM assay was performed by the manufacturer. Among 456 specimens tested, the iM reference method detected M. pneumoniae in 25 specimens (5.5%), while the iMD assay identified 34 specimens (7.5%) as M. pneumoniae positive. There were 10 false-positive results and 1 false-negative result with the iMD assay. The overall positive and negative agreement rates were 96.0% (95% confidence interval [CI], 80.5 to 99.3%) and 97.7% (95% CI, 95.8 to 98.7%), respectively. The overall agreement rate was determined to be 97.6% (95% CI, 95.7 to 98.6%). We conclude that the iMD test results were comparable to the iM assay results. The removal of the DNA extraction step for the iMD assay simplifies testing, saves time, and reduces the costs of detecting M. pneumoniae from throat swabs, compared to the iM assay.

Closing the Brief Case: Dyspnea in a Profoundly Immunocompromised Man

1. Paecilomyces species may display various pigmentation; however, isolates never appear: Answer: c. The surface color of Paecilomyces species recovered in culture can be variable; however, the color is never blue-green, as seen with Penicillium species. 1. Paecilomyces species have

166Rapid MRSA PCR on Respiratory Specimens from Ventilated Patients with Suspected Pneumonia: A Potential Tool for Antimicrobial Stewardship

166. Rapid MRSA PCR on Respiratory Specimens from Ventilated Patients with Suspected Pneumonia: A Potential Tool for Antimicrobial Stewardship Sergio E. Trevino, MD; Morgan A. Pence, PhD; Jonas Marschall, MD; Marin H. Kollef, MD; Hilary M. Babcock, MD, MPH; Carey-Ann D. Burnham, PhD; Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO; Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO; Department of Infectious Diseases, Bern University Hospital and University of Bern, Bern, Switzerland; Pulmonary and Critical Care Medicine, Washington University School of Medicine, St. Louis, MO; Pediatrics, Pathology and Immunology, Washington University School of Medicine, St Louis, MO

Answer to November 2014 Photo Quiz

Answer: Acute bacterial meningitis due to Streptococcus pneumoniae. The Gram-positive, lancet-shaped diplococci observed in this specimen are characteristic of Streptococcus pneumoniae. A cerebrospinal fluid (CSF) specimen Gram stain result such as this should be promptly relayed to the clinician