Diagnostic SARS-CoV-2 Cycle Threshold Value Predicts Disease Severity, Survival, and Six-Month Sequelae in COVID-19 Symptomatic Patients
Mattia Trunfio,
Francesco Venuti,
Francesca Alladio,
Bianca Maria Longo,
Elisa Burdino,
Francesco Cerutti,
Valeria Ghisetti,
Roberto Bertucci,
Carlo Picco,
Stefano Bonora,
Giovanni Di Perri,
Andrea Calcagno
Affiliations
Mattia Trunfio
Unit of Infectious Diseases, Department of Medical Sciences, University of Torino at the Amedeo di Savoia Hospital, Corso Svizzera 164, 10149 Torino, Italy
Francesco Venuti
Unit of Infectious Diseases, Department of Medical Sciences, University of Torino at the Amedeo di Savoia Hospital, Corso Svizzera 164, 10149 Torino, Italy
Francesca Alladio
Unit of Infectious Diseases, Department of Medical Sciences, University of Torino at the Amedeo di Savoia Hospital, Corso Svizzera 164, 10149 Torino, Italy
Bianca Maria Longo
Unit of Infectious Diseases, Department of Medical Sciences, University of Torino at the Amedeo di Savoia Hospital, Corso Svizzera 164, 10149 Torino, Italy
Elisa Burdino
Microbiology and Molecular Biology Laboratory, Amedeo di Savoia Hospital, ASL Città di Torino, Corso Svizzera 164, 10149 Torino, Italy
Francesco Cerutti
Microbiology and Molecular Biology Laboratory, Amedeo di Savoia Hospital, ASL Città di Torino, Corso Svizzera 164, 10149 Torino, Italy
Valeria Ghisetti
Microbiology and Molecular Biology Laboratory, Amedeo di Savoia Hospital, ASL Città di Torino, Corso Svizzera 164, 10149 Torino, Italy
Roberto Bertucci
Unit of Infectious Diseases, Department of Medical Sciences, University of Torino at the Amedeo di Savoia Hospital, Corso Svizzera 164, 10149 Torino, Italy
Carlo Picco
Regional Department for Infectious Diseases and Emergency DIRMEI, ASL Città di Torino, Via S. Secondo 29, 10128 Torino, Italy
Stefano Bonora
Unit of Infectious Diseases, Department of Medical Sciences, University of Torino at the Amedeo di Savoia Hospital, Corso Svizzera 164, 10149 Torino, Italy
Giovanni Di Perri
Unit of Infectious Diseases, Department of Medical Sciences, University of Torino at the Amedeo di Savoia Hospital, Corso Svizzera 164, 10149 Torino, Italy
Andrea Calcagno
Unit of Infectious Diseases, Department of Medical Sciences, University of Torino at the Amedeo di Savoia Hospital, Corso Svizzera 164, 10149 Torino, Italy
To date, there is no severe acute respiratory syndrome coronavirus 2-(SARS-CoV-2)-specific prognostic biomarker available. We assessed whether SARS-CoV-2 cycle threshold (Ct) value at diagnosis could predict novel CoronaVirus Disease 2019 (COVID-19) severity, clinical manifestations, and six-month sequelae. Hospitalized and outpatient cases were randomly sampled from the diagnoses of March 2020 and data collected at 6 months by interview and from the regional database for COVID-19 emergency. Patients were stratified according to their RNA-dependent-RNA-polymerase Ct in the nasopharyngeal swab at diagnosis as follows: Group A ≤ 20.0, 20.0 28.0. Disease severity was classified according to a composite scale evaluating hospital admission, worst oxygen support required, and survival. Two hundred patients were included, 27.5% in Groups A and B both, 45.0% in Group C; 90% of patients were symptomatic and 63.7% were hospitalized. The median time from COVID-19 onset to swab collection was five days. Lethality, disease severity, type, and number of signs and symptoms, as well as six-month sequelae distributed inversely among the groups with respect to SARS-CoV-2 Ct. After controlling for confounding, SARS-CoV-2 Ct at diagnosis was still associated with COVID-19-related death (p = 0.023), disease severity (p = 0.023), number of signs and symptoms (p p < 0.01). Early quantification of SARS-CoV-2 may be a useful predictive marker to inform differential strategies of clinical management and resource allocation.