Acute Bronchitis

Aka: Acute Bronchitis, Bronchitis, Chest Cold

1. See Also
   1. Chronic Bronchitis
   2. Acute Exacerbation of Chronic Bronchitis
   3. Chronic Cough
   4. Acute Cough Causes
2. Definition
   1. Infection of trachea, Bronchi, or Bronchioles
   2. Acute Bronchitis is most often of viral etiology
      1. Chronic Bronchitis exacerbation is usually bacterial
3. Epidemiology
   1. Acute Bronchitis is most common cause of acute cough
      1. Cough is most common presenting symptom in primary care
4. Etiology: Most common causes by age
   1. Age under one year
      1. Respiratory Syncytial Virus (winter to spring)
      2. Parainfluenza Virus (fall)
      3. Coronavirus (winter to spring)
   2. Age one to 10 years
      1. Parainfluenza Virus (fall)
      2. Enterovirus (fall)
      3. Respiratory Syncytial Virus (winter to spring)
      4. Rhinovirus (fall)
   3. Age over 10 years
      1. Influenza virus (winter to spring)
      2. Respiratory Syncytial Virus (winter to spring)
      3. Adenovirus
5. Etiology: By Category
   1. Viral Causes (represent >90% of causes)
      1. Adenovirus
      2. Coronavirus
      3. Influenza
      4. Metapneumovirus
      5. Parainfluenza virus
      6. Respiratory Syncytial Virus (RSV)
      7. Rhinovirus
   2. Bacterial causes
      1. Streptococcus Pneumoniae (Pneumococcus)
      2. HaemophilusInfluenzae
      3. Moraxella catarrhalis (Branhamella catarrhalis)
      4. Bordetella pertussis (and parapertussis)
   3. Atypical Bacterial causes
      1. Mycoplasma pneumoniae
      2. Chlamydia pneumoniae
      3. Legionella
   4. Yeast or fungi
      1. Blastomyces dermatitidis
      2. Candida albicans (and tropicalis)
      3. Coccidioides immitis
      4. Cryptococcus neoformans
      5. Histoplasma capsulatum
   5. Environmental irritants (noninfectious triggers)
      1. Air Pollution
      2. Ammonia
      3. Marijuana
      4. Tobacco smoke
6. Symptoms
   1. Cough (onset within 2 days in 85% of Acute Bronchitis)
      1. Cough often dry, non-productive
      2. Cough may be productive of variably colored Sputum (does not distinguish from Pneumonia)
   2. Dyspnea
   3. Wheezing
   4. Chest Pain
   5. Hoarseness
   6. Constitutional symptoms
      1. Fever
      2. Myalgias
      3. Fatigue
7. Signs
   1. Low grade fever
      1. High fever suggests Pneumonia or Influenza
   2. Lung auscultation
      1. Rales or Rhonchi variably present
      2. Prolonged expiration
      3. No signs of consolidation (Pneumonia)
         1. Lung sounds symmetric
         2. No focal rales
8. Diagnostics
   1. Sputum exam not indicated unless Pneumonia suspected
   2. Pulse oximetry may be indicated in severe illness
   3. Peak Flow values may be indicated in Asthma history
   4. C-Reactive Protein (CRP)
      1. Value <20 suggests Bronchitis (instead of Pneumonia)
      2. Hopstaken (2003) Br J Gen Pract 53:358-64
9. Radiology: Chest XRay Indications
   1. Red flags
      1. High fever
      2. Tachypnea
      3. Tachycardia
      4. Asymmetric lung sounds
   2. Pulmonary cause of cough suspected
      1. Pneumonia
      2. Congestive Heart Failure
   3. Serious comorbid condition
      1. Elderly patient
      2. Chronic Obstructive Lung Disease
      3. Immunocompromised patient
      4. Malignancy history
      5. Recent history of pulmonary process
         1. Pneumonia
         2. Tuberculosis
10. Differential Diagnosis
    1. See Acute Cough Causes
    2. Asthma
    3. Rhinitis or Sinusitis with post-nasal drainage
    4. Pneumonia
       1. Predictors
          1. C-Reactive Protein >20
          2. Erythrocyte sedimentaion rate increased
          3. Dry cough with Diarrhea, Nausea
          4. Temperature >38 C (>100.4 F)
       2. References
          1. Hopstaken (2003) Br J Gen Pract 53:358-64
11. Management: Symptomatic
    1. Supportive care for viral illness
    2. Inhaled Bronchodilator (e.g. Albuterol)
       1. More recent reviews suggest no benefit in Bronchitis unless Wheezing
          1. Direct use to those with Wheezing on examination
          2. Schroeder (2004) Cochrane Database Syst Rev CD001831
       2. Initial review suggested benefit in shortening Bronchitis course
          1. Hueston (1994) J Fam Pract 39:437-40
    3. Inhaled Corticosteroids (high dose) for episode
       1. McKean (2000) Cochrane Database Syst Rev CD001107
    4. Symptomatic relief of cough (especially nighttime)
       1. Cough suppression risks worsening bronchospasm
       2. Dextromethorphan is not effective in children with Bronchitis
          1. Paul (2004) Pediatrics 114(1):e85-90
       3. See Cough Suppressant (Antitussive)
       4. Avoid Albuterol Syrup (Not helpful)
          1. Littenberg 1996 J Fam Pract 42:49-53)
    5. Pelargonium sidoides (herbal product)
       1. Decreases overall symptoms compared with Placebo
       2. Return to work 2 days earlier compared with Placebo
       3. Matthys (2003) Phytomedicine 10:7-17
12. Management: Specific Circumstances
    1. Treat suspected underlying cause of cough
       1. See Cough Management
       2. See Chronic Cough
    2. Persistent post-Bronchitic cough
       1. Bronchodilators reduce symptom severity and duration
       2. Consider Inhaled Corticosteroid (e.g. Azmacort)
13. Management: Antibiotics
    1. Most cases are viral and do not require antibiotics
       1. Most studies show minimal if any antibiotic benefit
          1. No benefit with Azithromycin
          2. Evans (2002) Lancet 359:1648-54
       2. Patients with cough under 1 week showed no benefit
       3. Most patients improve with or without antibiotics
       4. See Antibiotic Resistance for Patient Education
    2. Productive cough short duration (<1 week)
       1. Avoid antibiotics
       2. Treat symptomatically as above
    3. Productive cough longer than 1-2 weeks
       1. Evaluate for treatable and serious causes of cough
          1. Pneumonia (consider Chest XRay)
          2. Acute Sinusitis
          3. Bordatella Pertussis
          4. Influenza A (treat within first 36 hours of symptoms)
          5. Tuberculosis (consider PPD)
       2. Reassurance
          1. Observation is reasonable if otherwise healthy
          2. Bronchitis often lasts >2 weeks (see course below)
          3. Consider Inhaled Corticosteroid
       3. Antibiotic protocol
          1. Consider using acute phase reactant markers to distinguish higher risk cases
             1. Procalcitonin
                1. Christ-Crain (2004) Lancet 363(9409):600-7
             2. C-Reactive Protein
                1. Cals (2009) BMJ 338: b1374
          2. Consider treating high risk groups
             1. Age over 65 years
             2. Chronic Obstructive Lung Disease
                1. See Acute Exacerbation of Chronic Bronchitis
          3. Antibiotics have no benefit empirically in Bronchitis
             1. Evans (2002) Lancet 359(9318): 1648-54
             2. Smucny (1998) J Fam Pract 47(6): 453-60
          4. Antibiotic selection (empiric use not recommended)
             1. Adult under age 50 years
                1. Macrolide antibiotic or
                2. Doxycycline
             2. Adult over age 50 years
                1. Third Generation Fluoroquinolone (e.g. Levaquin)
14. Precautions
    1. Avoid suppressing cough if possible
       1. Cough intended to clear lungs, protect from Pneumonia
15. Course
    1. Cough persists for >2 weeks in 25% of patients
    2. Cough may persist as long as 8 weeks in some patients
16. Resources: Patient Education
    1. Information from your Family Doctor
       1. http://www.familydoctor.org/handouts/677.html
17. References
    1. Albert (2010) Am Fam Physician 82(11): 1345-50
    2. Knutson (2002) Am Fam Physician 65(10):2039-44