What is the initial management for a patient presenting with acute bronchitis, considering symptoms and potential underlying respiratory conditions like Chronic Obstructive Pulmonary Disease (COPD) or asthma?

Initial Management of Acute Bronchitis

For patients presenting with acute bronchitis, antibiotics should NOT be prescribed routinely, as they provide minimal benefit (reducing cough by only half a day) while exposing patients to adverse effects and contributing to antibiotic resistance. 1

Immediate Diagnostic Assessment

Before confirming acute bronchitis, you must systematically exclude pneumonia and other serious conditions by evaluating the following vital signs and examination findings 2, 1:

• Heart rate >100 beats/min 2
• Respiratory rate >24 breaths/min 2
• Oral temperature >38°C 2
• Chest examination findings of focal consolidation, egophony, or fremitus 2

If ANY of these findings are present, obtain a chest radiograph to rule out pneumonia rather than treating as simple bronchitis. 2, 1

Critical Differential Diagnoses to Exclude

Asthma and COPD Exacerbation

• Approximately one-third of patients diagnosed with acute bronchitis actually have undiagnosed asthma, making this the most commonly missed diagnosis 1
• In patients with recurrent "acute bronchitis" episodes, 65% actually have mild asthma rather than repeated infections 1
• For patients with known COPD or asthma, this presentation may represent an acute exacerbation requiring bronchodilators or corticosteroids, not simple acute bronchitis 1

Pertussis

• Consider pertussis if the patient has severe paroxysms of coughing, post-tussive vomiting, or the characteristic whooping sound 2, 1
• Epidemiologic linkage to a confirmed pertussis case strongly supports this diagnosis 2

Evidence-Based Treatment Approach

What NOT to Prescribe

Antibiotics are contraindicated in uncomplicated acute bronchitis because 2, 1:

• Viruses cause 89-95% of cases 1, 3
• Antibiotics reduce cough duration by only 0.5 days 1, 4
• They significantly increase adverse events (RR 1.20; 95% CI, 1.05-1.36) 1
• Purulent or green sputum occurs in 89-95% of viral cases and does NOT indicate bacterial infection 1

Additional medications to avoid 1:

• Routine β2-agonist bronchodilators (unless wheezing is present)
• Inhaled or oral corticosteroids
• NSAIDs at anti-inflammatory doses
• Expectorants or mucolytics
• Antihistamines

What TO Prescribe

Symptomatic treatment only 1, 5:

• Codeine or dextromethorphan may provide modest relief for bothersome dry cough, especially when sleep is disturbed 1
• β2-agonist bronchodilators should be considered ONLY in select patients with accompanying wheezing 1

The Pertussis Exception

If pertussis is confirmed or strongly suspected, immediately prescribe a macrolide antibiotic (erythromycin or azithromycin) and isolate the patient for 5 days from treatment initiation. 1 Early treatment within the first few weeks diminishes coughing paroxysms and prevents disease spread 1.

Special Populations: COPD and Asthma

Standard acute bronchitis recommendations do NOT apply to patients with underlying COPD or asthma. 1

For COPD Exacerbations

Consider antibiotics if the patient meets Anthonisen criteria (at least 2 of 3) 1:

• Increased dyspnea
• Increased sputum volume
• Increased sputum purulence

AND has high-risk features such as 1:

• Age >65 years with moderate-to-severe COPD
• Cardiac failure
• Insulin-dependent diabetes
• Chronic respiratory insufficiency (FEV1 <35%, PaO2 <60 mmHg)

Recommended antibiotic regimens for COPD exacerbations 1:

• First-line: Doxycycline 100 mg twice daily for 7-10 days
• For severe exacerbations: Amoxicillin-clavulanate 625 mg three times daily for 14 days
• Duration: 7-10 days for most cases, up to 14 days for documented bacterial pathogens

Essential Patient Education

Set realistic expectations to maintain satisfaction without prescribing unnecessary antibiotics 2, 1:

• Cough typically lasts 10-14 days after the visit, even without treatment 1, 5
• The condition is self-limiting and resolves within 3 weeks 1, 5
• Antibiotics will not meaningfully shorten the illness but will expose them to side effects 1

Refer to the condition as a "chest cold" rather than "bronchitis" to reduce patient expectations for antibiotics 1.

Critical Reassessment Criteria

Instruct patients to return if 1, 5:

• Fever persists >3 days (suggests bacterial superinfection or pneumonia, not simple viral bronchitis)
• Cough persists >3 weeks (transitions to subacute/chronic cough; consider asthma, upper airway cough syndrome, GERD, or pertussis)
• Symptoms worsen rather than gradually improve

Common Pitfalls to Avoid

1. Do not assume bacterial infection based on 1:

   • Sputum color or purulence (present in 89-95% of viral cases)
   • Duration of cough alone
   • Patient expectation for antibiotics

2. Do not miss underlying asthma, especially in patients with 1:

   • Recurrent episodes of "acute bronchitis"
   • Accompanying wheezing
   • History of atopy or allergies

3. Do not prescribe antibiotics for smokers without COPD—they have no greater need than nonsmokers 2

4. Do not use simple aminopenicillins for COPD exacerbations, as up to 25% of H. influenzae and 50-70% of M. catarrhalis produce β-lactamase 1

Clinical Algorithm Summary

1. Evaluate vital signs and chest examination → If abnormal, consider pneumonia and obtain chest radiograph 2, 1
2. Rule out asthma/COPD exacerbation, especially if recurrent episodes or wheezing present 1
3. Consider pertussis if paroxysmal cough, post-tussive vomiting, or epidemiologic linkage 2, 1
4. If uncomplicated acute bronchitis confirmed: Provide education on expected 2-3 week duration and symptomatic treatment only 1, 5
5. Reserve antibiotics ONLY for: Confirmed/suspected pertussis OR high-risk COPD patients meeting Anthonisen criteria 1
6. Schedule reassessment if fever >3 days, cough >3 weeks, or worsening symptoms 1, 5