Lack of correlation between the SARS-CoV-2 cycle threshold (C ) value and clinical outcomes in patients with COVID-19.

PROBLEM

The utility of the polymerase chain reaction (PCR) cycle threshold (C ) values in the management of patients with coronavirus disease 2019 (COVID-19) remains controversial.

METHODS

We assessed the correlation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) C values in nasopharyngeal swab samples with the oxygen requirements at the time of sample collection. Specimens were tested with the Simplexa PCR platform, which targets the SARS-CoV-2 ORF1ab and S genes.

RESULTS

We identified 23 COVID-19 patients with 49 C values available. While C values from ORF1ab and S genes were highly correlated for a given specimen, there was no correlation between C values for any of these target genes and the oxygen requirements of the patient at the time of sample collection. We found no differences in the initial nor the nadir C values between survivors and non-survivors or mild/moderate versus severe/critical illness at the maximum point of illness.

CONCLUSION

SARS-CoV-2 C values have limited value in the management of COVID-19.