Abstract
Introduction: The alarming infection rates of COVID-19 and variability in disease severity and outcome created the need for a prognostic marker to predict disease severity, prioritize services, and assist in clinical decision-making. The cycle threshold (Ct) value was hypothesized to be inversely correlated with viral load and subsequently disease severity. Therefore, it gained clinical interest and was an important topic for research. In this study, we aimed to determine the accuracy of the Ct value as a predictor of clinical severity in children presenting to the emergency department with COVID-19. Specifically, we aimed to compare the relationship between clinical severity among patients with high vs. low Ct values as well as to assess the correlation between the mean Ct value with the mean number of symptoms.
Methods: This is a single-center retrospective cohort study. Data were obtained from the electronic medical record software of King Abdulaziz Medical City in Jeddah, Saudi Arabia. The present study included randomly selected COVID-19 cases aged ≥1 months to 18 years who presented to the emergency department between March 2020 and May 2021. Collected clinical data were matched with laboratory data at the time of diagnosis to examine the association between Ct values and clinical factors.
Results: A total of 191 COVID-19 PCR-positive children were included with an overall mean Ct value of 11.5, a median of 10, and a highest Ct value of 25. The mean age of the patients was 95 months. More than half (51.35%) of the patients were admitted to the hospital, while 2.09% were admitted to the intensive care unit and one patient (0.52%) died. There was no significant association between Ct values and demographics or clinical characteristics of the patients.
Conclusion: We demonstrated a lack of association between SARS-CoV-2 Ct value detected in nasopharyngeal swabs with disease severity, number of symptoms, oxygen requirement, intensive care unit admission, or length of hospital stay in the pediatric population presenting to the emergency department with COVID-19. This finding does not support the routine reporting of Ct values to aid clinicians in making clinical and patient-management decisions for COVID-19 patients or guide infection control or public health decisions. Further studies confirming our observations are needed.