What antibiotics are used empirically in COVID-19 patients?

Empirical Antibiotic Use in COVID-19 Patients

Antibiotics should NOT be routinely prescribed in COVID-19 patients unless there is clinical suspicion of bacterial co-infection, with specific exceptions for critically ill patients and those with clear signs of bacterial infection. 1

Assessment for Bacterial Co-infection

• Bacterial co-infections are uncommon in COVID-19 patients, particularly at the time of admission, supporting a restrictive approach to antibiotic use 1

• Clinical indicators that may warrant empirical antibiotics include:

  • Critically ill patients requiring ICU admission or mechanical ventilation 1, 2
  • Radiological findings compatible with bacterial pneumonia 1, 2
  • Elevated inflammatory markers (WBC count, CRP, procalcitonin >0.5 ng/mL) 1, 3
  • Immunocompromised status 1, 4
  • Patients with COVID-19 and shock 1

• Before starting antibiotics, obtain appropriate cultures:

  • Sputum and blood cultures 1, 2
  • Pneumococcal urinary antigen testing 1, 2
  • Legionella urinary antigen testing (according to local guidelines) 1, 2

Antibiotic Selection Based on Illness Severity

For Non-Critically Ill Patients with Suspected Bacterial Co-infection:

• Follow local/national guidelines for community-acquired pneumonia 1, 2
• Recommended options include:
  • Beta-lactams such as amoxicillin or third-generation cephalosporins 2, 5
  • For atypical coverage, consider doxycycline rather than macrolides due to potential cardiac side effects 2, 5

For Critically Ill Patients with Suspected Bacterial Co-infection:

• Consider empirical anti-MRSA antibiotics in selected patients 1, 2
• For secondary bacterial infections, consider antipseudomonal coverage based on local epidemiology 1, 6
• Common pathogens to cover include Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, and Pseudomonas aeruginosa 2, 5, 6

Duration and De-escalation

• If cultures are negative and patient is improving, stop antibiotics after 48 hours 1, 4
• For confirmed bacterial infections, a 5-7 day course is typically sufficient if the patient has reached clinical stability 1, 2
• Consider using procalcitonin levels to guide early discontinuation of antibiotics 1, 3

Common Pitfalls to Avoid

• Overuse of antibiotics in COVID-19 patients without evidence of bacterial co-infection increases antimicrobial resistance without improving outcomes 7, 8
• Studies show that 58-78% of COVID-19 patients receive antibiotics despite bacterial co-infection being uncommon (5.5% at ICU admission) 7, 8
• Serum biomarkers alone should not determine when to start antibiotics, especially in non-critically ill patients 1, 3
• Not all radiographic abnormalities in COVID-19 patients indicate bacterial co-infection; they may be due to the viral infection alone 2, 9
• Empirical use of broad-spectrum antibiotics like meropenem and fluoroquinolones has been associated with increased mortality in some studies 10, 9

Specific Antibiotic Considerations

• Cephalosporins are among the most commonly prescribed antibiotics for COVID-19 patients 11, 8
• Macrolides (particularly azithromycin) have shown some potential benefit in certain COVID-19 patients, though this remains controversial 9, 11
• When covering for atypical pathogens, doxycycline may be preferred over macrolides in patients receiving other QT-prolonging medications 2, 5

By following these evidence-based guidelines, clinicians can make appropriate decisions about empirical antibiotic use in COVID-19 patients, balancing the need to treat potential bacterial co-infections while minimizing unnecessary antibiotic use that contributes to antimicrobial resistance.