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PCR Cycle Threshold Values and COVID-19 Outcomes

Can Quantitative (Real-time) Polymerase Chain Reaction (PCR) Cycle Threshold (Ct) Values be Used to Predict Poor Outcomes for Patients Infected With SARS-CoV-2? A Local Exploratory Sub-study at The University Hospitals of North Midlands NHS Trust in Collaboration With the International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) COVID-19 Trial

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04651413
Enrollment
934
Registered
2020-12-03
Start date
2020-11-24
Completion date
2021-10-14
Last updated
2022-05-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Covid19

Brief summary

This is a retrospective observational study. The study will use high quality, reliable data that has already been collected for the ISARIC 4C COVID-19 study in order to analyse the relation between predictor variables (laboratory polymerase chain reaction \[PCR\] cycle threshold \[Ct\] values) and outcomes for COVID-19 disease within a hospitalised population.

Detailed description

Currently, in the United Kingdom, the recommended method for diagnostic testing and screening for COVID-19 is quantitative (real-time) reverse transcription polymerase chain reaction (PCR) analysis of viral RNA extracted from upper respiratory tract samples. A positive result indicates that SARS-CoV-2 RNA has been detected with a cycle threshold (Ct) value of less than 38 cycles of amplification (n.b. this is a locally agreed value, which is based on analysis of proficiency testing performance and other local testing data. Cycle threshold (Ct) values inversely correlate to the amount of target nucleic acid in the sample. Thus, a lower cycle threshold (Ct) value indicates a greater amount of target nucleic acid in a sample i.e. a higher viral load. A recent scoping literature review has revealed only a handful of published studies to date that explore an association between cycle threshold (Ct) values and disease severity or clinical outcome in patients infected with the SARS-CoV-2 virus. The majority of these studies have been conducted in China with small patient sample sizes. Thus, a larger-scale study which explores the relationship between viral load and disease severity is required; indeed, the World Health Organization (WHO) has recently highlighted this as an area which needs further research.

Interventions

DIAGNOSTIC_TESTPCR Value

Data collection and interpretation

Sponsors

University Hospitals of North Midlands NHS Trust
Lead SponsorOTHER

Study design

Observational model
OTHER
Time perspective
RETROSPECTIVE

Eligibility

Sex/Gender
ALL
Healthy volunteers
Yes

Inclusion criteria

1. Adult (aged 18 years and over) patients presenting to UHNM with confirmed SARS-CoV-2 infection AND who are enrolled onto the ISARIC COVID-19 study. 2. Patients who have undergone an initial diagnostic or screening test for SARS-CoV-2 (from an upper respiratory tract sample) AND a cycle threshold (Ct) value is available on the UHNM laboratory database.

Exclusion criteria

1. Paediatric patients (under 18 years). 2. Patients without a PCR Ct result on the UHNM laboratory database 3. Patients without confirmed SARS-CoV-2 infection 4. Patients who were not enrolled in to the ISARIC COVID-19 study

Design outcomes

Primary

MeasureTime frameDescription
Determine if there is an inverse correlation with risk of poor outcome including admission to intensive care; mechanical ventilation and 28-day mortality.01/02/2020 to 01/07/2020Determine if cycle threshold (Ct) levels are an independent predictor for: I. Hypoxia resulting in oxygen dependency or oxygen saturations \< 92%, at admission and at any other point during the episode of care; II. admission to intensive care; III. mechanical ventilation and

Secondary

MeasureTime frameDescription
Differences in cycle threshold (Ct) levels amongst patients with community acquired SARS-CoV-201/02/2020 to 01/07/2020Determine if sociodemographic factors are significantly associated with lower cycle threshold (Ct) levels.

Countries

United Kingdom

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026