Development and performance of a multiplex PCR assay for the detection of bacteria in sterile body fluids.

Aim: To assess the performance characteristics of a lab-developed multiplex PCR assay for the detection of common bacterial pathogens associated with infections in pediatric patients from normally sterile sites, such as cerebrospinal fluid, synovial and pleural fluids. Materials & methods: A total of 272 specimens were tested by PCR and traditional culture methods to assess the presence of Neisseria meningitidis, Streptococcus pneumoniae, Streptococcus pyogenes, methicillin-sensitive and methicillin-resistant Staphylococcus aureus and Kingella kingae. Results: Compared with culture, the overall positive and negative percentage agreement of the PCR were 95.9% and 74.1%, respectively. Conclusion: This sterile body fluid PCR affords a rapid and sensitive alternative for bacterial detection, allowing for more timely pathogen-directed antimicrobial therapy.

Clinical Validation and Performance Evaluation of the Automated Vitros Total Anti-SARS-CoV-2 Antibodies Assay for Screening of Serostatus in COVID-19.

OBJECTIVES: Evaluation of serostatus against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged as an important tool in identification of exposure to coronavirus disease 2019 (COVID-19). We report on the validation of the Vitros Anti-SARS-CoV-2 Total (CoV2T) assay for qualitative serologic testing of SARS-CoV-2 antibodies. METHODS: We performed validation studies according to Commission of Office Laboratories Accreditation guidelines, using samples previously tested for SARS-CoV-2 by reverse transcription-polymerase chain reaction (RT-PCR). We evaluated precision, analytical interferences, and cross-reactivity with other viral infections; evaluated concordance with molecular and other serologic testing; and evaluated seroconversion. RESULTS: The Vitros CoV2T assay exhibited acceptable precision and did not exhibit cross-reactivity with other acute respiratory virus infections. The CoV2T assay exhibited 100% negative predictive agreement (56/56) and 71% positive predictive agreement (56/79) with RT-PCR across all patient samples and was concordant with other serologic assays. Concordance with RT-PCR was 97% more than 7 days after symptom onset. The CoV2T assay was robust to icterus and lipemia but had interference from significant hemolysis. CONCLUSIONS: The Vitros CoV2T assay was successfully validated in our laboratory. We anticipate it will be a useful tool in screening for exposure to SARS-CoV-2; however, the use of the CoV2T and other serologic assays in the clinical management of patients with COVID-19 is unknown and must be evaluated in future studies.

Thoracic Paraspinal Castleman Disease in a Young Mexican-American Man with Postcoital Hematuria.

BACKGROUND: Castleman disease (CD) is an uncommon disorder of deregulated lymphoproliferation with unicentric (UCD) and multicentric forms based on extent of nodal involvement. Gross resection with histopathologic analysis remains the gold standard for diagnosis of UCD and is curative in most cases. Symptomatic paraspinal UCD is a rare presentation with potentially dangerous complications, and its tendency to mimic more common spinal tumors presents a significant diagnostic challenge. CASE PRESENTATION: A 25-year-old Hispanic man with no past medical history was evaluated for a known left-sided paraspinal mass that was incidentally discovered during an emergency department work-up for hematuria. Computed tomography on initial presentation revealed a 5.3 cm × 3.3 cm × 4.8 cm heterogeneously enhancing left paraspinal mass adjacent to the T11 vertebral body with tonguelike extension into the T11-T12 neural foramen. Although he remained neurologically intact throughout most of the diagnostic work-up, an inconclusive biopsy, worsening hematuria, and late-onset radiculopathy with severe back pain prompted surgical intervention. Microscopic histomorphology was consistent with CD. He continued to have intermittent hematuria and dysuria postoperatively, but repeat computed tomography at 7 months confirmed no recurrence of the mass. CONCLUSIONS: Compared with previous reports, our case of postcoital hematuria and radiculopathy accompanying a paraspinal thoracic mass in a young Mexican-American man is a unique presentation. Awareness and early consideration of UCD in the work-up of a paraspinal mass may spare affected patients adverse and dangerous sequelae, such as spinal cord compression and excessive intraoperative hemorrhage.