Faculty Bibliography

BACKGROUND:Outsourcing of microbiology laboratory services is a growing trend in US medical centers. Data on the actual impact of outsourcing on patient care, safety, and medical education, including costs, are limited. The objective of this study was to examine the published literature on the potential benefits and harms when medical centers outsource common microbiology services. METHODS:We conducted a 16-step literature search of PubMed and Embase. Articles were selected for full-text review if their content matched our key questions: (1) What are the potential benefits of outsourcing core microbiology laboratory testing? (2) What are the potential harms to patient care and medical education when medical centers outsource essential microbiology services? RESULTS:The initial search yielded 6111 unique published articles; 36 were selected for full-text review, which resulted in the identification of 8 articles that addressed our key questions (2 editorials, 3 editorials with observational data, 1 survey, 1 case series, and 1 study of blood culture transport). These articles described a variety of issues, including longer turnaround times for blood cultures that resulted in delays in diagnosis and treatment, errors that resulted in patient morbidity, limited cost savings, and communication barriers. CONCLUSIONS:In this study, with the exception of the blood culture transport study, we found no published prospective studies that quantified the effects of outsourcing microbiology services on patient care, patient safety, or medical education. However, these largely anecdotal reports suggest that outsourcing microbiology services may have a detrimental impact on medical education, especially infectious disease training programs.

BACKGROUND:Vitros ECiQ and Architect i2000 SR are two automated instruments used to detect serology biomarkers of hepatitis A, B and C viruses, and HIV infections. We compared performance of the Architect to the Vitro EciQ after implementation at our institution. METHODS:A retrospective review was performed to compare patient samples tested on the Vitros ECiQ or Architect for hepatitis and HIV serological assays. The positivity rate, frequency of equivocal results, turnaround times (TAT), and hands-on time (HOT) were analyzed. RESULTS:There was no statistical difference in the positivity rate between the two instruments, with the exception of two assays. An increase in equivocal results was observed for the Architect (0.2% vs 0.5%). Notably, the TAT for the Architect i2000 was shorter for all except one assay (31.6 vs 33.7 hours) and demonstrated improved workflow. CONCLUSIONS:Overall, both instruments performed comparably. Architect had shorter TAT over Vitros.

INTRODUCTION/BACKGROUND:Eikenella corrodens is a small, nonmotile Gram-negative rod that is part of the normal flora in the mouth, upper respiratory, gastrointestinal, and genitourinary tracts. It is classically found in human bite (fist to mouth) infections but is also seen in respiratory tract and head and neck infections. METHODS:We describe three cases of E. corrodens causing head and neck infections in children seen in our institution between 2013 and 2019. We also reviewed the available literature on pediatric head and neck infections caused by E. corrodens. RESULTS:All 3 children recovered and fit the trends identified in the 58 patients published in the literature from 1976 to 2019. CONCLUSIONS:E. corrodens is responsible for a range of head and neck infections in pediatric patients. It is a not infrequent cause of head and neck infections in children and should be considered when selecting presumptive antibiotic therapy.

Influenza is a contagious respiratory illness caused by influenza viruses A and B in humans and causes a significant amount of morbidity and mortality every year. The Influenza A and B assay was the first CLIA-waived molecular rapid flu test available. The Influenza A and B test works by employing isothermal amplification with influenza-specific primers followed by target detection with molecular beacon probes. Here, the performance of the Influenza A and B assay on frozen, archived nasopharyngeal swab (NPS) specimens stored in viral transport medium (VTM) were compared to a respiratory panel assay. The performance of the Influenza A and B assay was evaluated by comparing the results to the respiratory panel reference method. The sensitivity for total influenza virus A was 67.5% (95% CI (CI), 56.6-78.5) and the specificity was 86.9% (CI, 71.0-100). For influenza virus B testing, the sensitivity and specificity were 90.2% (CI, 68.5-100) and 98.8% (CI, 68.5-100), respectively. This system has the advantage of a significantly shorter test time than any other currently available molecular assay and the simple, pipette-free procedure runs on a fully integrated, closed, small-footprint system. Overall, the Influenza A and B assay evaluated in this study has the potential to serve as a point-of-care rapid influenza diagnostic test.

Discoveries associated with antibacterial activity of hydrated clays necessitate assessments of in vivo efficacy, practical use and safety. Surface properties of clays can lead to variations in the composition and abundance of bound compounds or ions, thus affecting antibacterial activity. Since exchangeable metal ions released from the clay surface are responsible for in vitro antibacterial activity, we evaluated the in vivo antibacterial efficacy of four natural clays (one illite clay, two montmorillonite clays and one kaolinite clay) and three ion-exchanged, antibacterial clays against superficial, cutaneous meticillin-resistant Staphylococcus aureus (MRSA) infections in mice. Superficial, cutaneous wounds on the back of SKH1-Elite mice were generated and subsequently infected with MRSA. Following twice daily applications of a hydrated clay poultice to infected wounds for 7  days, we observed significant differences in the in vivo antibacterial efficacy between different types of clays. The natural and ion-exchanged illite clays performed best, as measured by bacterial load, inflammatory response and gross wound morphology with significant decreases in bacterial viability and dermatitis. Topical application of kaolinite clay was the least effective, resulting in the lowest decrease in bacterial load and exhibiting severe dermatitis. These data suggest that specific types of clays may offer a complementary and integrative strategy for topically treating MRSA and other cutaneous infections. However, since natural clays exhibit in vitro antibacterial variability and vary vastly in surface chemistries, adsorptive/absorptive characteristics and structural composition, the properties and characteristics of illite clays could aid in the development of standardized and customized aluminosilicates for topical infections.

Arcobacter butzleri is an emerging pathogen that has been implicated as the causative agent of persistent watery diarrhea. We describe a case involving a patient with chronic lymphocytic leukemia who developed invasive A. butzleri bacteremia. This case illustrates the unique challenges involved in diagnosing infections caused by emerging gastrointestinal pathogens.

We implemented hospital information system (HIS) alerts to deter unnecessary test orders for ovum and parasite (O&P) exams and Clostridium difficile PCR. The HIS alerts decreased noncompliant O&P orders (orders after >72 h of hospitalization) from 49.8% to 30.9%, an overall decrease of 19%, and reduced noncompliant C. difficile PCR orders (orders <7 days after a previous positive result) from 30.6% to 19.2%, an overall decrease of 31.9%.

Prompt detection and identification of fungal pathogens at the genus and species level is critical in order to provide timely antifungal therapy. Here, we highlight the vital role of molecular diagnostics in achieving a fast and definitive diagnosis of disseminated blastomycosis in a diabetic patient presenting as a brain mass initially thought to be tumoral in nature. A broad-range PCR amplification and sequencing of the fungal ribosomal RNA genes on brain biopsy tissue obtained during elective craniotomy revealed a final microbial identification of Ajellomyces dermatitidis (telemorph of Blastomyces dermatitidis).

Aqueous leachates prepared from natural antibacterial clays, arbitrarily designated CB-L, release metal ions into suspension, have a low pH (3.4-5), generate reactive oxygen species (ROS) and H2O2, and have a high oxidation-reduction potential. To isolate the role of pH in the antibacterial activity of CB clay mixtures, we exposed three different strains of Escherichia coli O157:H7 to 10% clay suspensions. The clay suspension completely killed acid-sensitive and acid-tolerant E. coli O157:H7 strains, whereas incubation in a low-pH buffer resulted in a minimal decrease in viability, demonstrating that low pH alone does not mediate antibacterial activity. The prevailing hypothesis is that metal ions participate in redox cycling and produce ROS, leading to oxidative damage to macromolecules and resulting in cellular death. However, E. coli cells showed no increase in DNA or protein oxidative lesions and a slight increase in lipid peroxidation following exposure to the antibacterial leachate. Further, supplementation with numerous ROS scavengers eliminated lipid peroxidation, but did not rescue the cells from CB-L-mediated killing. In contrast, supplementing CB-L with EDTA, a broad-spectrum metal chelator, reduced killing. Finally, CB-L was equally lethal to cells in an anoxic environment as compared to the aerobic environment. Thus, ROS were not required for lethal activity and did not contribute to toxicity of CB-L. We conclude that clay-mediated killing was not due to oxidative damage, but rather, was due to toxicity associated directly with released metal ions.