The Essential Role of PCR and PCR Panel Size in Comparison with Urine Culture in Identification of Polymicrobial and Fastidious Organisms in Patients with Complicated Urinary Tract Infections.

Complicated urinary tract infections (cUTIs) are difficult to treat, consume substantial resources, and cause increased patient morbidity. Data suggest that cUTI may be caused by polymicrobial and fastidious organisms (PMOs and FOs, respectively); as such, urine culture (UC) may be an unreliable diagnostic tool for detecting cUTIs. We sought to determine the utility of PCR testing for patients presumed to have a cUTI and determine the impact of PCR panel size on organism detection. We reviewed 36,586 specimens from patients with presumptive cUTIs who received both UC and PCR testing. Overall positivity rate for PCR and UC was 52.3% and 33.9%, respectively (p < 0.01). PCR detected more PMO and FO than UC (PMO: 46.2% vs. 3.6%; FO: 31.3% vs. 0.7%, respectively, both p < 0.01). Line-item concordance showed that PCR detected 90.2% of organisms identified by UC whereas UC discovered 31.9% of organisms detected by PCR (p < 0.01). Organism detection increased with expansion in PCR panel size from 5-25 organisms (p < 0.01). Our data show that overall positivity rate and the detection of individual organisms, PMO and FO are significantly with PCR testing and that these advantages are ideally realized with a PCR panel size of 25 or greater.

The Impact of Systematic Safety Precautions on COVID-19 Risk Exposure and Transmission Rates in Outpatient Healthcare Workers.

We evaluated the impact of safety protocols, including rapid testing and contact tracing, on coronavirus disease 2019 (COVID-19) risk exposure and transmission rates amongst healthcare workers in the outpatient care setting. Over an 11-week period, a total of 254 employees representing 38% of our total workforce had potential COVID-19 exposure and underwent voluntary COVID-19 testing. Data was stratified based on severity of risk exposure and job description. During this period, the probability of a COVID exposure being high risk decreased in Administrative (-93.0%; P < 0.01) and Clinical (-77.0%; P < 0.01) staff; simultaneously, viral transmission rates declined in Administrative (-73.4%; P = 0.03) and Clinical (-69.9%; P = 0.04) staff as well. Systematic safety protocols effectively reduce exposure risk and transmission rates in outpatient healthcare workers and should be ubiquitously adopted.

Multiregion Comprehensive Genomic Profiling of a Gastric Mixed Neuroendocrine-Nonneuroendocrine Neoplasm with Trilineage Differentiation.

Mixed neuroendocrine-nonneuroendocrine neoplasms (MiNENs) are a group of rare tumors previously known as mixed adenoneuroendocrine carcinomas (MANECs). The neuroendocrine component is high-grade and may consist of small-cell carcinoma or large-cell neuroendocrine carcinoma. The nonneuroendocrine component may consist of adenocarcinoma or squamous cell carcinoma. We report a unique case of a MiNEN with trilineage differentiation: large-cell neuroendocrine carcinoma, squamous cell carcinoma, and adenocarcinoma. The reported patient presented with symptoms of an upper gastrointestinal bleed and was ultimately diagnosed with a MiNEN with trilineage differentiation. This is the first report of this exceedingly rare tumor type to include next-generation sequencing of the 3 separate tumor entities. In addition, we review the current literature and discuss the role of next-generation sequencing in classifying and treating MiNEN tumors.

Targeted deletion in the beta20-beta21 loop of HIV envelope glycoprotein gp120 exposes the CD4 binding site for antibody binding.

Different isolates of HIV-1 are known to vary in antibody binding and sensitivity to neutralization. In response to selective pressure, the virus may conceal important neutralizing determinants, such as the CD4 binding site on gp120, through steric hindrance or conformational masking. The 3D structure of gp120 shows five loop structures that surround the CD4 binding site (CD4BS) and may restrict antibody access to the site. We have generated gp120 mutants lacking each of these loops and characterized them with a panel of monoclonal antibodies, including b12 and F105. A targeted deletion in the beta20-beta21 loop resulted in gp120 with enhanced binding of both monoclonals. Enhancement of b12 binding suggests reduced steric hindrance, since the antibody is relatively insensitive to conformation. Enhanced binding of F105, which depends strongly on the protein conformation, suggests that the mutation may allow gp120 to move more freely into the liganded form. The same viral strategies that limit antibody binding may also inhibit antibody induction. Modified forms of gp120, in which the CD4 binding site is more exposed and accessible to antibodies, could provide novel immunogens for eliciting antibodies to this broadly shared neutralizing determinant.