Diagnostic Performance of Multiplex Nucleic Acid Testing of Bronchoalveolar Lavage and Bronchial Wash Specimens for Respiratory Viral Pathogens

ABSTRACTThere is limited knowledge on the yield of performing multiplex nucleic acid testing (NAT) on multiple lower respiratory tract specimens from a single patient with a single instance of infection. We evaluated the performance characteristics of multiplex NAT assays performed concurrently on bronchoalveolar lavage (BAL) and bronchial wash (BW) specimens to detect respiratory pathogens. A retrospective study of admitted patients from March 2013 through December 2016 was performed. Individual performance characteristics of BAL and BW specimens were compared to positive results from either set of specimens. Only contemporaneous BAL and BW specimens (received by the laboratory within 4 h of each other) were included. The final cohort included 170 patients, with 184 contemporaneous BAL and BW specimens submitted for multiplex NAT (median age, 58 years; 62% male). Of the patients with positive NAT results, 38 of 40 BW specimens tested positive (overall percent agreement with combined testing, 98.9%; 95% confidence interval [CI], 95.5 to 98.9%), and 34 of 40 BAL specimens tested positive (overall percent agreement with combined testing, 96.7%; 95% CI, 93.0 to 96.7%). Assays performed on BW specimens identified 4 additional specimens and had a higher positive percent agreement (95.0%) with combined testing results compared to those performed on BAL specimens (85.0%). There was exact concordance in 174 specimens (94.6%; negative and positive for respiratory pathogens, 144 and 34 specimens, respectively). We observed high concordance (95%) between multiplex NAT results from contemporaneous BAL and BW specimens. Performance characteristics of BW specimen testing were equivalent to those of BAL specimen testing. The benefit of performing additional testing should be carefully considered against the potential complications and health care costs.

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Evaluation of Performance Characteristics of Panther Fusion Assays for Detection of Respiratory Viruses from Nasopharyngeal and Lower Respiratory Tract Specimens

Journal of Clinical Microbiology ◽

10.1128/jcm.00787-18 ◽

2018 ◽

Vol 56 (8) ◽

Cited By ~ 10

Author(s):

Soya S. Sam ◽

Angela M. Caliendo ◽

Jessica Ingersoll ◽

Deborah Abdul-Ali ◽

Charles E. Hill ◽

...

Keyword(s):

Respiratory Tract ◽

Positive Result ◽

Lower Respiratory Tract ◽

Influenza A ◽

Performance Characteristics ◽

Influenza B Virus ◽

Influenza B ◽

Respiratory Pathogens ◽

Percent Agreement ◽

Syncytial Virus

ABSTRACT Accurate and rapid diagnosis is needed for timely intervention and clinical management of acute respiratory infections. This study evaluated performance characteristics of the Panther Fusion assay for the detection of influenza A virus (Flu A), influenza B virus (Flu B), respiratory syncytial virus (RSV), parainfluenza viruses 1 to 3 (Para 1 to 3), human metapneumovirus (hMPV), rhinovirus (RV), and adenovirus (Adeno) targets in comparison to those of the eSensor and Lyra assays using 395 nasopharyngeal (NP) and 104 lower respiratory tract (LRT) specimens. Based on the consensus positive result established (positive result in 2 of the 3 assays), the NP specimens for the Fusion and eSensor assays had 100% positive percent agreement (PPA) for all the analytes and the Lyra assays had 100% PPA for Flu A and Adeno analytes. A 100% negative percent agreement (NPA) was observed for all the Lyra analytes, whereas those for the Fusion targets ranged from 98.4 to 100% and those for the eSensor ranged from 99.4 to 100% for all the analytes except RV. For the LRT specimens, Fusion had 100% PPA and 100% NPA for all the targets except hMPV. There was a 100% PPA for eSensor analytes; the NPA ranged from 98 to 100%, except for RV. For the Lyra assays, the PPA ranged between 50 and 100%, while the NPA was 100% for all the targets except Adeno. The Fusion assay performed similarly to the eSensor assay for majority of the targets tested and provides laboratories with a fully automated random-access system to test for a broad array of viral respiratory pathogens.

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Test performance characteristics of quantitative nucleic acid testing for polyomaviruses in kidney and kidney-pancreas transplant recipients

Clinical Transplantation ◽

10.1111/ctr.12195 ◽

2013 ◽

pp. n/a-n/a ◽

Cited By ~ 1

Author(s):

T.M.M. Myint ◽

R.M. Turner ◽

J.C. Craig ◽

N.B. Cross ◽

K. Kable ◽

...

Keyword(s):

Nucleic Acid ◽

Test Performance ◽

Performance Characteristics ◽

Pancreas Transplant ◽

Nucleic Acid Testing ◽

Transplant Recipients

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Comparison of two commercial platforms and a laboratory developed test for detection of SARS-CoV-2 RNA

10.1101/2020.07.03.20144758 ◽

2020 ◽

Cited By ~ 3

Author(s):

Laura Mannonen ◽

Hannimari Kallio-Kokko ◽

Raisa Loginov ◽

Anu Jaaskelainen ◽

Pia Jokela ◽

...

Keyword(s):

Nucleic Acid ◽

The Other ◽

Nucleic Acid Testing ◽

Reference Standard ◽

Critical Importance ◽

Clinical Laboratories ◽

Percent Agreement ◽

Hands On ◽

Respiratory Specimens ◽

Higher Sensitivity

Mitigation of the ongoing COVID-19 pandemic requires reliable and accessible laboratory diagnostic services. We evaluated the performance of one LDT and two commercial tests, cobas® SARS-CoV-2 (Roche) and Amplidiag® COVID-19 (Mobidiag), for the detection of SARS-CoV-2 RNA in respiratory specimens. 183 specimens collected from suspected COVID-19 patients were studied with all three methods to compare their performance. In relation to the reference standard, which was established as the result obtained by two of the three studied methods, the positive percent agreement (PPA) was highest for cobas® test (100%), followed by Amplidiag® test and the LDT (98.9%). The negative percent agreement (NPA) was lowest for cobas® test (89.4%), followed by Amplidiag® test (98.8%) and the highest value was obtained for LDT (100%). The dilution series conducted for specimens, however, suggests significantly higher sensitivity for the cobas® assay in comparison with the other two assays and the low NPA value may be due to the same reason. In general, all tested assays performed adequately. Both the time from sample to result and hands-on time per sample were shortest for cobas® test. Clinical laboratories need to be prepared for uninterrupted high-throughput testing during the coming months in mitigation of the pandemic. To secure that, it is of critical importance for clinical laboratories to maintain several simultaneous platforms in their SARS-CoV-2 nucleic acid testing.

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Elevated white blood cell count does not predict Clostridium difficile nucleic acid testing results

Clinical Infectious Diseases ◽

10.1093/cid/ciab106 ◽

2021 ◽

Author(s):

Dustin E Bosch ◽

Patrick C Mathias ◽

Niklas Krumm ◽

Andrew Bryan ◽

Ferric C Fang ◽

...

Keyword(s):

Nucleic Acid ◽

Clostridium Difficile ◽

Blood Cell ◽

Cell Count ◽

Prognostic Marker ◽

White Blood Cell Count ◽

White Blood Cell ◽

Inpatient Setting ◽

Nucleic Acid Testing ◽

Blood Cell Count

Abstract Background An elevated white blood cell count (>15 thousand/μL) is an established prognostic marker in patients with Clostridium difficile infection (CDI). Small observational studies have suggested that a markedly elevated WBC should prompt consideration of CDI. However, there is limited evidence correlating WBC elevation with the results of C. difficile nucleic acid testing (NAAT). Methods Retrospective review of laboratory testing, outcomes, and treatment of 16,568 consecutive patients presenting to 4 hospitals over four years with NAAT and WBC testing on the same day. Results No significant relationship between C. difficile NAAT results and concurrent WBC in the inpatient setting was observed. Although an elevated WBC did predict NAAT results in the outpatient and emergency department populations (p<0.001), accuracy was poor, with receiver-operator areas under the curve of 0.59 and 0.56. An elevated WBC (>15 thousand/μL) in CDI was associated with a longer median hospital length of stay (15.5 vs. 11.0 days, p<0.01), consistent with leukocytosis as a prognostic marker in CDI. NAAT-positive inpatients with elevated WBC were more likely to be treated with metronidazole and/or vancomycin (relative ratio 1.2, 95% confidence interval 1.1–1.3) and die in the hospital (relative ratio 2.9, 95% CI 2.0–4.3). Conclusions Although WBC is an important prognostic indicator in patients with CDI, an isolated WBC elevation has low sensitivity and specificity as a predictor of fecal C. difficile NAAT positivity in the inpatient setting. A high or rising WBC in isolation is not a sufficient indication for CDI testing.

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