How should I manage an acute exacerbation of infective bronchitis in an adult, including indications for antibiotics, bronchodilators, steroids, and supportive care?

Management of Acute Exacerbation of Infective Bronchitis in Adults

For acute exacerbations of infective bronchitis, treat with 14 days of oral antibiotics targeting Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis, using amoxicillin 500-1000 mg three times daily as first-line therapy, reserving antibiotics for patients with increased sputum purulence, increased sputum volume, and increased dyspnea. 1, 2

Diagnostic Assessment and Antibiotic Indications

Antibiotics are indicated when patients present with at least two of the three Anthonisen criteria: 1, 2

• Increased sputum purulence
• Increased sputum volume
• Increased dyspnea

Additional features supporting bacterial infection include fever, worsening cough, and systemic symptoms. 1, 2

Obtain sputum for culture and sensitivity before starting antibiotics, particularly in hospitalized patients or those with severe disease. 1 This allows for antibiotic adjustment if clinical response is inadequate. 1, 3

Perform chest radiography in hospitalized patients to exclude pneumonia, which requires different management. 2, 3

First-Line Antibiotic Selection

Amoxicillin 500-1000 mg three times daily for 14 days is the recommended first-line treatment for most patients. 1, 2 This provides excellent coverage against the three most common pathogens. 1

For beta-lactamase producing H. influenzae or M. catarrhalis, use amoxicillin-clavulanate 625 mg three times daily for 14 days. 1

Second-Line and Alternative Options

If amoxicillin is contraindicated or ineffective: 1

• Doxycycline 100 mg twice daily for 14 days 1
• Clarithromycin 500 mg twice daily (shorter duration possible due to prolonged half-life) 1, 2
• Azithromycin 500 mg on day 1, then 250 mg daily for 5 days 1, 2

Special Considerations for Pseudomonas Risk

For patients with risk factors for Pseudomonas aeruginosa (frequent exacerbations, prior isolation, severe bronchiectasis, recent hospitalization), use ciprofloxacin 500-750 mg twice daily for 14 days as first-line oral therapy. 1, 3

If parenteral therapy is required, options include: 1

• Intravenous ciprofloxacin
• Ceftazidime 2g three times daily
• Piperacillin-tazobactam 4.5g three times daily

Duration of Treatment

The standard duration is 14 days for bacterial bronchitis exacerbations. 1, 2 This recommendation comes from the British Thoracic Society and European Respiratory Society guidelines, based on studies showing optimal bacterial clearance and symptom resolution with this duration. 1

Shorter courses of 7 days may be considered for mild exacerbations in low-risk patients, though evidence supporting equivalence is limited. 1, 2

Assessing Treatment Response

Fever should resolve within 2-3 days of starting appropriate antibiotic therapy. 1, 2 This is the primary criterion for treatment response. 1

If no improvement occurs by day 3: 1, 3

• Obtain sputum culture if not already done
• Consider chest radiography to exclude pneumonia
• Reassess for non-infectious causes (pulmonary embolism, heart failure, inadequate bronchodilator therapy)
• Consider antibiotic resistance or atypical pathogens

Management of Treatment Failure

In non-responding patients, perform microbiological reassessment and switch to an antibiotic with broader coverage against resistant S. pneumoniae, P. aeruginosa, and other pathogens. 1, 3

Recommended switches include: 1, 3

• Respiratory fluoroquinolones (levofloxacin 500-750 mg daily or moxifloxacin 400 mg daily) for patients without pseudomonas risk 3
• Ciprofloxacin 500-750 mg twice daily for pseudomonas coverage 1, 3
• Consider intravenous therapy if oral route fails or patient deteriorates 1

Adjust antibiotics based on culture results once available. 1, 3

Supportive Care

While antibiotics are the cornerstone, provide concurrent supportive measures: 4

• Bronchodilators for airflow obstruction
• Adequate hydration
• Removal of environmental irritants
• Consider short course of oral corticosteroids in severe exacerbations with significant airflow limitation 4

Critical Pitfalls to Avoid

Do not assume viral etiology and withhold antibiotics when purulent sputum and increased volume are present—these indicate bacterial infection requiring treatment. 1, 2, 4 The older research suggesting antibiotics are unnecessary conflicts with current guideline recommendations based on more recent evidence showing benefit in appropriately selected patients. 5

Do not use the same antibiotic class that has failed, as this suggests resistance or inadequate spectrum. 3

Do not treat for less than 14 days in standard cases, as shorter courses may lead to incomplete bacterial clearance and earlier recurrence. 1, 6