COVID-19 Diagnostic Workup and Treatment Recommendations
For patients with suspected COVID-19, RT-PCR testing of respiratory specimens is the gold standard diagnostic approach, while treatment should be tailored based on disease severity, with early antiviral therapy recommended for high-risk patients. 1
Diagnostic Workup
Initial Testing
- RT-PCR testing of respiratory specimens (nasopharyngeal and throat swabs) should be performed as soon as possible after symptom onset for optimal sensitivity 1
- If initial RT-PCR is negative but clinical suspicion remains high, repeat testing after 24 hours (RT-PCR sensitivity is approximately 70%) 1
Additional Diagnostic Considerations
- Chest imaging is NOT recommended for asymptomatic patients or when RT-PCR testing is available with timely results 1
- Chest imaging IS recommended when:
- RT-PCR testing is unavailable or delayed
- RT-PCR is negative but clinical suspicion remains high
- Patient presentation suggests complications 1
- Comprehensive microbiologic workup before administering empirical antibiotics to facilitate appropriate antibiotic management 2
Disease Severity Classification
COVID-19 severity can be classified as 1:
- Mild: Various symptoms without respiratory distress
- Moderate: Lower respiratory disease with SpO2 ≥94% on room air
- Severe: SpO2 <94% on room air
- Critical: Requires ICU admission or mechanical ventilation
Treatment Approach
For High-Risk Patients
High-risk factors include: age ≥65 years, obesity, cardiovascular disease, chronic lung disease, immunocompromised status, diabetes, chronic kidney disease 1
- Initiate antiviral therapy within 5-7 days of symptom onset 1
- Preferred antiviral option: Nirmatrelvir-ritonavir (Paxlovid) 300 mg/100 mg twice daily for 5 days, with dose adjustments for patients with eGFR 30-59 mL/min 1
- Alternative antiviral options if Nirmatrelvir-ritonavir is contraindicated:
For Hospitalized Patients
- Non-critical hospitalized patients: 5-day course of remdesivir 1, 3
- Patients requiring mechanical ventilation or ECMO: 10-day course of remdesivir 3
- For patients requiring oxygen: Consider corticosteroids 1
- For severe inflammatory response: Consider tocilizumab 1
For Low-Risk Patients
- Symptomatic management includes maintaining hydration, paracetamol for fever, and honey for cough 1
- Virtual follow-up in 1-2 weeks 1
Management of Co-Infections
- Higher WBC counts, elevated CRP, or PCT >0.5 ng/mL may indicate bacterial co-infection, but these markers alone should not determine antibiotic use 2
- For suspected bacterial co-infection in non-critically ill patients, use empirical antibiotics covering both typical and atypical CAP pathogens 2
- For critically ill patients with suspected bacterial co-infection, consider adding anti-MRSA coverage 2
- For suspected secondary bacterial infections in non-critically ill patients, a single anti-pseudomonal antibiotic is recommended 2
Monitoring During Treatment
- Perform hepatic laboratory testing in all patients before starting and while receiving remdesivir 3
- Determine prothrombin time before starting and monitor while receiving remdesivir 3
- For patients with COVID-19, follow center protocols for SARS-CoV-2 monitoring 2
Common Pitfalls to Avoid
- Delaying testing after symptom onset
- Relying on a single negative RT-PCR when clinical suspicion is high
- Failing to consider drug interactions with Nirmatrelvir-ritonavir
- Unnecessary hospitalization of mild cases
- Overuse of antibiotics without evidence of bacterial co-infection
- Delaying antiviral therapy in high-risk patients 1
Discharge Criteria
Patients can be discharged when they have:
- Been fever-free for >3 days
- Significant improvement in respiratory symptoms
- Significant absorption of pulmonary lesions on imaging
- Two consecutive negative nucleic acid tests (≥24 hours apart) 1