Chronic Cough

1. See Also
   1. Pediatric Chronic Cough
2. Definition
   1. Cough duration longer than 8 weeks
3. Causes
   1. See Chronic Cough Causes
4. History
   1. Tobacco Smoking
      1. Packs per day
      2. Morning cough
   2. Post-nasal drainage (typically presents with Globus sensation)
      1. Allergic Rhinitis
      2. Sinusitis
   3. Asthma
      1. Night cough
      2. Environmental irritants
      3. Atopic Family History
   4. Gastroesophageal Reflux
      1. Cough Worse supine (exception in Reflux Laryngitis which is worse in upright position)
      2. Cough relieved with antacids?
      3. Frequent throat clearing
   5. Chronic Bronchitis
      1. Productive cough
      2. Tobacco Smoker
   6. Medications
      1. ACE Inhibitors
   7. Airway Hyperresponsive
      1. Recent Upper Respiratory Infection or Bronchitis
         1. Bordatella Pertussis
         2. Chlamydia pneumoniae
         3. Mycoplasma pneumoniae
         4. Influenza
         5. RSV
         6. Parainfluenza
      2. Non-productive cough
   8. Cancer or Tuberculosis Symptoms
      1. Night Sweats
      2. Hemoptysis
      3. Weight loss
5. Radiology
   1. Chest XRay
      1. Indicated in most cases of Chronic Cough
      2. Conditions resulting in abnormal findings
         1. Bronchiectasis
         2. Bronchogenic Carcinoma
         3. Tuberculosis
         4. Sarcoidosis
         5. Peristant Pneumonia
   2. Chest CT Indications
      1. Elucidate abnormal Chest XRay
6. Management: Initial Interventions
   1. General
      1. Consider Chest XRay unless cause is obvious
      2. Algorithm applies to non-urgent cough evaluation
      3. Immunocompromised patients require urgent evaluation
   2. Avoid Lung toxins
      1. Tobacco Cessation
      2. See Occupational Asthma
   3. Discontinue ACE Inhibitor if using
      1. Convert to Angiotensin Receptor Blocker
      2. Reassess after 4 weeks
   4. If suspect post-Bronchitis airway hyper-responsiveness
      1. Consider Inhaled Corticosteroids
      2. Consider inhaled Ipratropium Bromide (Atrovent)
   5. If Suspect Chronic Bronchitis
      1. Tobacco Cessation
      2. Bronchodilators
   6. Consider infectious cause evaluation
      1. Purified Protein Derivative (PPD) for Tuberculosis
      2. Nasopharyngeal swab PCR for Bordetella pertussis
7. Management: Step 1 - Treat empirically for postnasal drip
   1. Diagnoses to consider
      1. Upper Airway Cough Syndrome (UACS)
      2. Acute Sinusitis or Chronic Sinusitis
      3. Allergic Rhinitis
      4. Vasomotor Rhinitis
   2. Medications to consider
      1. Consider Decongestant and Antihistamine combination
      2. Consider using first generation Antihistamine
         1. Example: Chlorpheniramine
         2. Non-Sedating Antihistamine may not be potent enough
      3. Intranasal Corticosteroids
      4. Atrovent nasal inhaler (Vasomotor Rhinitis)
      5. Consider Acute Sinusitis Management
   3. Imaging to consider
      1. Sinus XRay or CT Sinuses
8. Management: Step 2 - Evaluate for Asthma
   1. Consider cough-variant Asthma empiric trial
      1. Trial Bronchodilator with or without Inhaled Corticosteroid (e.g. Albuterol, advair)
      2. Trial Leukotriene Receptor Antagonist (e.g. Singulair)
      3. Consider prednisone 40 mg orally daily for 7-10 days
   2. Perform Pulmonary Function Tests
      1. FEV1 before and after Bronchodilator
      2. Consider Methacholine Challenge test
         1. High false positive rate (25%)
         2. Near 100% Negative Predictive Value
   3. Treat Asthma if present
      1. See Allergan Control
      2. Inhaled Corticosteroids or Cromolyn Sodium
      3. Inhaled Beta Agonist
9. Management: Step 3 - Evaluate Pulmonary and Sinus Disease
   1. Chest XRay (if not already done)
   2. CT Sinuses
10. Management: Step 4 - Treat for Gastroesophageal Reflux
    1. High Dose Proton-Pump Inhibitor
       1. Omeprazole (Prilosec) 20 to 80 mg PO qd
       2. Requires 2-3 months of therapy to eliminate cough
    2. Anti-Reflux Esophagitis measures
    3. Consider diagnostic testing
       1. Upper GI
       2. Upper Endoscopy
       3. 24 hour esophageal pH monitoring
11. Management: Step 5 - Advanced lung diagnostics
    1. Consider Eosinophilic Bronchitis evaluation
       1. Obtain 3 induced Sputum samples
       2. Negative if Eosinophils <3% in Sputum
       3. Responds to oral or Inhaled Corticosteroids
    2. Pulmonology consultation
       1. Bronchoscopy may be considered
    3. If pulmonary evaluation negative
       1. Repeat Asthma medications
       2. Repeat Antihistamine and Decongestant combinations
    4. Evaluate for less common etiologies
       1. See Chronic Cough Causes
12. References
    1. Holmes (2004) Am Fam Physician 69(9):2159-66
    2. Irwin (2000) N Engl J Med 343:1715-21
    3. Smyrnios (1995) Chest 108:991-7
    4. Philip (1997) Am Fam Physician 56(5): 1395-1402
    5. Benich (2011) Am Fam Physician 84(8): 887-92