Facklamia Species as an Underrecognized Pathogen.

Facklamia species are a rarely reported etiology of clinical infection with few cases described in literature. However, the prevalence of infection may be underestimated due to challenges in species identification. We describe 3 cases of Facklamia species bacteremia and the unique microbiologic aspects inherent to this genus that make it particularly challenging to identify. In addition, given the unique susceptibility profile of Facklamia species, we discuss the importance of fully identifying this organism when it is a suspected as a pathogen, to optimize therapy based on its distinct antibiotic resistance profile.

Application of Nuclear Magnetic Resonance to Detect Toxigenic Clostridium difficile from Stool Specimens: A Proof of Concept.

We evaluated the performance of an early prototype core molecular mirroring nuclear magnetic resonance detection platform (Mentor-100) to detect toxigenic Clostridium difficile from stool. This technology uses customized nanoparticles bound to target specific oligonucleotide probes that form binaries in the presence of nucleic acid from the target microorganism. Liquid patient stool specimens were seeded with C. difficile or other Clostridium species to determine the analytical sensitivity and specificity. Samples underwent nucleic acid extraction and target amplification with probes conjugated with iron nanoparticles. Signal from nuclear magnetic resonance spin-spin relaxation time was measured to detect the presence or absence of toxigenic C. difficile. The limit of detection was <180 colony forming units per reaction of toxigenic C. difficile. No cross-reactivity was observed with nontoxigenic C. difficile, Clostridium sordellii, Clostridium perfringens, Bacillus subtilis, or Paenibacillus polymyxa at 108 colony forming units/mL. Correlation studies using frozen stool samples yielded a sensitivity of 88.4% (61 of 69) and a specificity of 87.0% (40 of 46) as compared with a commercial PCR assay for C. difficile. The area under the curve in the receiver operating characteristic curve analysis was 0.922. The prototype molecular mirroring platform showed promising performance for pathogen detection from clinical specimens. The platform design has the potential to offer a novel, low-cost alternative to currently available nucleic acid-based tests.

The value of a multiplexed gastrointestinal pathogen panel in 2 distinct patient populations.

We assess the value of the Luminex xTAG Gastrointestinal Pathogen Panel (GPP) in 2 different patient populations: an uninsured, indigent population seeking primary care, and a tertiary care hospital specializing in surgical, transplant, and oncology care. Stool specimens collected April to August 2013 for infectious workup were tested on the GPP, and discordant results were further analyzed by alternative methods. Compared to the tertiary care setting, stool pathogen detection was nearly twice as frequent in the primary care setting (25% versus 14%; P<0.05) with a broader array of pathogens detected (15 versus 4). Overall, the greatest value of the GPP was in detection of viral causes of gastroenteritis that were not routinely sought and in detection of Campylobacter spp. when patients presented late in the disease course. Application of a GPP should consider the characteristics of the patient population to maximize its clinical utility in different healthcare settings.