When should bronchitis be treated with antibiotics?

When to Treat Bronchitis with Antibiotics

Antibiotics should NOT be prescribed for acute bronchitis in otherwise healthy adults, as the benefit has not been confirmed in clinical trials versus placebo. 1

Acute Bronchitis in Healthy Adults

• Acute bronchitis is usually viral in origin and does not require antibiotic treatment 1, 2
• Symptomatic treatment is recommended instead of antibiotics for uncomplicated acute bronchitis 1, 3
• Meta-analyses show only a small benefit from antibiotics (approximately half a day reduction in symptoms), which does not justify their use considering the risk of side effects and increasing antibiotic resistance 3, 4
• Consider antibiotics only if fever (>38°C) persists for more than 3 days, suggesting possible bacterial infection 1, 5

Chronic Bronchitis Exacerbations

The decision to use antibiotics depends on the stage of chronic bronchitis:

1. Simple Chronic Bronchitis

• Immediate antibiotic therapy is not recommended, even if fever is present 5, 6
• Consider antibiotics only if fever (>38°C) persists for more than 3 days 5, 6
• Characterized by chronic cough and expectoration without dyspnea, FEV1>80% 5

2. Obstructive Chronic Bronchitis

• Immediate antibiotic therapy is recommended only when at least two of the three Anthonisen criteria are present: 5, 6, 1
  • Increased sputum volume
  • Increased sputum purulence
  • Increased dyspnea
• Characterized by exertional dyspnea and/or FEV1 between 35% and 80% 5
• Purulent sputum or change in sputum color alone does not necessarily indicate bacterial infection 1

3. Chronic Respiratory Insufficiency

• Immediate antibiotic therapy is recommended during exacerbations 5, 6, 1
• Characterized by dyspnea at rest and/or FEV1 <35% and hypoxemia at rest (PaO2 <60 mmHg or 8 kPa) 5

Antibiotic Selection When Indicated

First-line Options:

• Amoxicillin remains the reference compound for infrequent exacerbations in patients with FEV1 ≥35% 5, 1
• First-generation cephalosporins are an alternative 5, 1
• For penicillin allergy: macrolides, pristinamycin, or doxycycline 5, 6, 1

Second-line Options (for treatment failures or frequent exacerbations):

• Amoxicillin-clavulanate (reference second-line therapy) 1
• Second or third-generation oral cephalosporins 1
• Fluoroquinolones active against pneumococci (levofloxacin, moxifloxacin) 1, 7

Target Pathogens

Antibiotic therapy should target the most common bacterial pathogens in bronchitis:

• Streptococcus pneumoniae 5, 1, 8
• Haemophilus influenzae 5, 1, 8
• Moraxella catarrhalis (formerly Branhamella catarrhalis) 5, 1, 8

Common Pitfalls to Avoid

• Prescribing antibiotics for acute bronchitis in healthy adults without clear indications 1, 3
• Assuming purulent sputum indicates bacterial infection 1
• Failing to distinguish between acute bronchitis and pneumonia 1
• Using cotrimoxazole, which has inconsistent activity against pneumococci and a poor benefit/risk ratio 5
• Using fluoroquinolones inactive against pneumococci (ofloxacin, ciprofloxacin) 1
• Failing to recognize when patients with chronic bronchitis have progressed to a more severe stage requiring different management 9

Clinical Follow-up

• Fever should resolve within 2-3 days after initiating appropriate treatment 6
• Persistence of fever >38°C after 3 days suggests bacterial infection or pneumonia 5, 1
• Reevaluation is essential after 2-3 days if symptoms persist or worsen 5