Abstract
BackgroundThere is limited and controverting evidence looking at possible associations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA copies and patient variables in large cohorts of symptomatic and asymptomatic patients.MethodsWe studied 2275 symptomatic and asymptomatic patients from Colombia with coronavirus disease 2019 (COVID-19) and analyzed the associations between RT-PCR cycle threshold (Ct) value with gender, age, comorbidities, symptomatology, and disease severity.Results15.4 % of the samples (n = 428) reported at least one comorbidity. There were 2011 symptomatic cases (72.4 %), being the most common reported symptom cough (57.2 %, n = 1586). Respiratory distress was present in 21.4 % of patients (n = 595), and 435 patients (15.6 %) required hospital admission. We observed that patients with no prior medical history harbored higher RNA copies than patients with comorbidities (p = 0.02). No significant differences in RNA copies were observed between symptomatic and asymptomatic patients (p = 0.82). Strong correlations were detected between Ct values and the presence of odynophagia (p = 0.03), diarrhea (p = 0.04), and headache (p = 0.0008). An inverse association was found between RNA copy number and markers of disease severity, namely, respiratory distress (P < 0.0001) and hospitalization requirement (P < 0.0001).ConclusionsSARS-CoV-2 RT-PCR cycle thresholds reveal strong associations with a prior medical history, specific symptomatology, and disease severity markers. Further research controlling potential confounding variables needs to be conducted to evaluate the nature and usefulness of these associations in managing COVID-19 patients.
Highlights
There is limited and controverting evidence looking at possible associations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA copies and patient variables in large cohorts of symptomatic and asymp‐ tomatic patients
Physicians obtained the samples during the evaluation of patients with suspected COVID-19 across various inpatient and outpatient settings across the department of Cundinamarca (Samples from Bogotá were not included in this study) in central Colombia (Additional file 1: Figure S1)
Detection of the E gene was carried using the primers/probe sets described in the Berlin Charité protocol [37] and human ribonuclease P gene (RP) was detected as an internal control [38] using the script enzyme XLT 1-Step RT-qPCR ToughMix L-ROX Kit (Ref. 95134-02 K, Quanta)
Summary
There is limited and controverting evidence looking at possible associations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA copies and patient variables in large cohorts of symptomatic and asymp‐ tomatic patients. A key aspect in response to the COVID-19 pandemic has been the early detection and prompt isolation of infected patients [4] For this purpose, real-time reverse transcriptase-polymerase chain reaction (RT-PCR) has been regarded as the gold standard diagnostic test [5], with an estimated 70 and 95 % sensitivity and specificity, respectively [6] RT-PCR reveals the broadest range of detection: becoming positive days before symptom onset and detecting viral nucleic acids up to several weeks in infected patients [7,8,9]. It is essential to clarify that test performance may differ due to the inherent variability between assays, extraction method/instrument combination, targeted regions of the viral genome, and clinical matrix tested. This makes standardization of Ct values and comparison across different platforms a challenging task
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Annals of Clinical Microbiology and Antimicrobials
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
