One-step and sequential SARSCOV-2 polymerase chain reaction tests would not work every time

Area of Science:

• Medical Diagnostics
• Infectious Disease Research
• Clinical Microbiology

Background:

• Reverse transcription-polymerase chain reaction (RT-PCR) is a primary method for SARS-CoV-2 detection.
• The clinical utility of serial RT-PCR testing for confirming COVID-19 requires further investigation.

Purpose of the Study:

• To evaluate the clinical utility of serial RT-PCR testing in the definitive diagnosis of COVID-19.
• To assess the yield of repeated RT-PCR tests following initial negative results.

Main Methods:

• Nasopharyngeal swab samples were collected from patients hospitalized with initial negative RT-PCR results.
• Serial RT-PCR testing was performed on days 2 and 3 for patients with persistent negative results.

Main Results:

• Among 68 patients with initial negative tests, 20 (29.4%) died.
• Subsequent positive RT-PCR results were observed in 33.8% of patients on the second test and 17.4% on the third test.

Conclusions:

• Serial RT-PCR testing offers limited additional diagnostic value for COVID-19 detection.
• The findings suggest that repeated testing may not significantly improve diagnostic yield after initial negative results.