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Review
. 2022 Jun;42(2):237-248.
doi: 10.1016/j.cll.2022.02.003. Epub 2022 Feb 21.

Cycle Threshold Values from Severe Acute Respiratory Syndrome Coronavirus-2 Reverse Transcription-Polymerase Chain Reaction Assays: Interpretation and Potential Use Cases

Alexander J McAdam  1
Affiliations
Review

Cycle Threshold Values from Severe Acute Respiratory Syndrome Coronavirus-2 Reverse Transcription-Polymerase Chain Reaction Assays: Interpretation and Potential Use Cases

Alexander J McAdam. Clin Lab Med. 2022 Jun.

Abstract

Reverse transcription-polymerase chain reaction (RT-PCR) tests for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), are approved for qualitative use. The cycle threshold (Ct) value reflects the concentration of viral RNA in the sample, with lower Ct values indicating higher levels of RNA. Caregivers may wish to use the Ct value to determine the progression of infection, how severe the infection will be, and whether the patient can transmit the virus. Variability of Ct values and the data supporting these uses should be considered when deciding whether and how to use Ct values in clinical care.

Keywords: COVID-19; Cycle threshold value; Reverse transcription-polymerase chain reaction; SARS-CoV-2.

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Conflict of interest statement

Disclosure The author has nothing to disclose.

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References

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