Performance of a Semiquantitative Multiplex Bacterial and Viral PCR Panel Compared With Standard Microbiological Laboratory Results: 396 Patients Studied With the BioFire Pneumonia Panel.

BACKGROUND: Microbiologic results are critical to optimal management of patients with lower respiratory tract infection, but standard methods may take several days. The multiplex polymerase chain reaction BioFire Pneumonia (PN) panel detects 15 common bacterial species semiquantitatively as copy number/mL, 8 viral species, and 7 resistance genes in about an hour within the clinical laboratory. METHODS: We tested 396 unique endotracheal or bronchoalveolar lavage specimens with the BioFire Pneumonia panel and compared the bacterial detections to conventional gram stain and culture results. RESULTS: Of the 396 patients, 138 grew at least 1 bacterium that had a target on the PN panel, and 136/138 (98.6%) were detected by the panel. A total of 177 isolates were recovered in culture and the PN panel detected 174/177 (98.3%). A further 20% of patients had additional targets detected that were not found on standard culture (specificity 69%, positive predictive value 63%, and negative predictive value 98.9%). Copy number was strongly related to standard semiquantitative growth on plates reported by the laboratory (eg, 1+, 2+, 3+ growths) and was significantly higher in those specimens that grew a potential pathogen. Both higher copy number and bacterial detections found by the PN panel, but not found in culture, were strongly positively related to the level of white blood cells reported in the initial gram stain. CONCLUSIONS: Higher copy number and bacterial detections by the PN panel are related to the host respiratory tract inflammatory response. If laboratories can achieve a rapid turnaround time, the PN panel should have a significant impact both on patient management and on antibiotic stewardship.

Implementation of an external female urinary catheter as an alternative to an indwelling urinary catheter.

BACKGROUND: Until recently, there has been a lack of viable alternative to an indwelling urinary catheter for female patients that require precise urine output measurements. With the introduction of external female urinary catheters, we can now substitute this type of device for an indwelling urinary catheter in many patients, decreasing their risk of catheter-associated urinary tract infections. METHODS: In this retrospective study, we analyzed the impact of a hospital-wide implementation of an external female urinary catheter at a large academic medical center. The study included female patients, greater than 18 years of age. We compared a 12-month period before and after device implementation to assess the impact on indwelling urinary catheter utilization and catheter-associated urinary tract infections rate. RESULTS: Data included over 220,000 patient days, over 10,000 external urinary catheter days and 33,000 indwelling urinary catheter days. We found a statistically significant decrease in indwelling urinary catheter utilization following the implementation of the external female urinary catheter, but only in intensive care units. CONCLUSIONS: It is our recommendation that facilities first implement the device in ICUs as this level of care was where we observed the most significant impact.

Educational Case: Identification of Pulmonary Mycobacteria.

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040.1.

Evaluating differences in tuberculosis and nontuberculous mycobacterial lung disease in Florida.

BACKGROUND: Currently, very little data exists that compare the features of pulmonary nontuberculous mycobacteria (NTM) and Mycobacterium tuberculosis (TB). Both have similar symptomology and analogous preliminary laboratory results, as both present with positive acid-fast bacilli stains. The objective of this study was to provide data that would help guide clinicians in their decision making regarding isolation precautions for patients, with a preliminary positive result for mycobacteria, prior to species identification. METHODS: We conducted queries for patients who had positive respiratory cultures for mycobacteria via our electronic medical record system, between January 1, 2011, and December 31, 2017. Additionally, we collected demographic and medical history, clinical presentation, and radiographic findings. The 2-sample unpaired Student t test, the Χ2 test, and logistic regression were used to compare each group. RESULTS: Through logistic regression, 8 variables were significantly associated with patients who grew either TB or NTM. History of incarceration, born outside of the United States, cavitation, and lymphadenopathy were associated with TB; tobacco smoke exposure, pre-existing lung disease, immunosuppression, and bronchiectasis were associated with NTM. Incidence of HIV and hemoptysis was not significantly different between the 2 groups. CONCLUSIONS: Through the use of our study findings, improper use of airborne isolation precautions may be reduced or avoided.

A Gastrointestinal PCR Panel Improves Clinical Management and Lowers Health Care Costs.

Conventional methods for the identification of gastrointestinal pathogens are time-consuming and expensive and have limited sensitivity. The aim of this study was to determine the clinical impact of a comprehensive molecular test, the BioFire FilmArray gastrointestinal (GI) panel, which tests for many of the most common agents of infectious diarrhea in approximately 1 h. Patients with stool cultures submitted were tested on the GI panel (n = 241) and were compared with control patients (n = 594) from the year prior. The most common organisms detected by the GI panel were enteropathogenic Escherichia coli (EPEC, n = 21), norovirus (n = 21), rotavirus (n = 15), sapovirus (n = 9), and Salmonella (n = 8). Patients tested on the GI panel had an average of 0.58 other infectious stool tests compared with 3.02 in the control group (P = 0.0001). The numbers of days on antibiotic(s) per patient were 1.73 in the cases and 2.12 in the controls (P = 0.06). Patients with the GI panel had 0.18 abdomen and/or pelvic imaging studies per patient compared with 0.39 (P = 0.0002) in the controls. The average length of time from stool culture collection to discharge was 3.4 days in the GI panel group versus 3.9 days in the controls (P = 0.04). The overall health care cost could have decreased by $293.61 per patient tested. The GI panel improved patient care by rapidly identifying a broad range of pathogens which may not have otherwise been detected, reducing the need for other diagnostic tests, reducing unnecessary use of antibiotics, and leading to a reduction in hospital length of stay.

Multiplex gastrointestinal pathogen panels: implications for infection control.

In the acute care hospital inpatient setting, there is a wide variety of causes for both infectious and noninfectious diarrhea. However, without molecular assays for the wide range of agents causing gastroenteritis, there is no reliable way to determine which individuals should be placed in contact precautions, as recommended by CDC. We tested 158 inpatient diarrheal stool specimens with the FilmArray GI Panel (BioFire Diagnostics, Salt Lake City, UT, USA) that had been stored at -70°C after testing negative by conventional methods for Clostridium difficile and/or rotavirus. We found that 22.2% had at least 1 other infectious agent detected, and 60% of these patients were never placed in appropriate isolation for a total of 109 patient-days. In addition, 20.3% of patients with negative GI panel results could have been removed from isolation. Use of multiplex gastrointestinal panels may improve decisions regarding patient isolation and reduce nosocomial transmission.