Predictors of negative first SARS-CoV-2 RT-PCR despite final diagnosis of COVID-19 and association with outcome”:
- Hypothesis: the clinical and biological characteristics of patients that returned a false-negative first RT-PCR result with a final diagnosis of being COVID-19 positive might be different from patients who returned a positive first RT-PCR test (ie. patients who are proven to have COVID-19 may have a negative first RT-PCR test early in their illness) and outcomes may be better for those with a negative first RT-PCR COVID-9 test than for those with a positive first test.
- Case-control study conducted included 80 patients (negative first test but later diagnosed with COVID-19) & 80 controls (positive first test) between March 30 – June 22
- Mortality at hospital discharge and hospital stay lengths did not differ between either group, ie. neither group differed significantly in terms of treatments received or need for medical ventilation equipment or hospital mortality.
- Two factors were independently associated with a smaller chance of a first false-negative RT-PCR test (headache and fatigue)
- Two factors were independently associated with a higher chance of a first false-negative RT-PCR test (platelets > 207 x 10^3 mm^-3 and C-reactive protein > 79.8 mgL^-3)
- The relationship between high CRP levels and greater risk of a first false-negative is interesting when considering the role cytokine storms have in severe COVID-19 cases