From the Guidelines
For a persistent non-productive cough lasting 3 weeks with no relief from azithromycin or steroids, and negative chest X-ray, I recommend a trial of inhaled ipratropium as it may attenuate the cough, as suggested by the American College of Chest Physicians evidence-based clinical practice guidelines 1. This approach is based on the consideration of postinfectious cough, which is a common cause of persistent cough after an acute respiratory infection. The guidelines suggest that therapy with antibiotics has no role in postinfectious cough, as the cause is not bacterial infection 1. In addition to inhaled ipratropium, consider a trial of inhaled corticosteroids if the cough persists and adversely affects the patient's quality of life, as recommended by the guidelines 1. Some key points to consider in the diagnosis and management of cough include:
- Postinfectious cough can persist for weeks after a respiratory infection has resolved
- Upper airway cough syndrome, asthma, and gastroesophageal reflux disease should be ruled out before considering other causes of cough
- Inhaled ipratropium and corticosteroids may be effective in attenuating the cough
- Pulmonary function testing and referral to pulmonology or ENT may be warranted if symptoms persist beyond 8 weeks. It is also important to note that nonasthmatic eosinophilic bronchitis is a common cause of chronic cough, and can be diagnosed by assessing lower airway inflammation through induced sputum analysis or bronchial wash fluid obtained at bronchoscopy, as described in the guidelines for chronic cough due to nonasthmatic eosinophilic bronchitis 1. However, given the patient's symptoms and the lack of response to azithromycin or steroids, a trial of inhaled ipratropium is a reasonable next step before pursuing more invasive testing.
From the Research
Next Steps for Non-Productive Cough
Given the patient's symptoms of non-productive cough for 3 weeks with no relief from Z-pack or steroids, a normal chest X-ray, no GERD, and overall feeling fine, the next steps can be considered as follows:
- The patient's condition does not seem to be related to common causes such as asthma, post-nasal drip syndrome (PNDS), or gastro-oesophageal reflux (GOR) as these were ruled out by the lack of response to steroids and the absence of GERD symptoms 2.
- Further diagnostic tests such as histamine challenge, home peak flow measurements, ear, nose and throat (ENT) examination, sinus CT scanning, and 24 hour oesophageal pH monitoring may be necessary to identify the underlying cause of the cough 2.
- Non-pharmacological therapies such as education, cough suppression, breathing techniques, mindfulness, and continuous positive airway pressure may be considered as they have shown to improve cough-specific health related quality of life, cough frequency, and voice outcomes in patients with refractory chronic cough 3.
- Intranasal azelastine and fluticasone as combination therapy may be an option for treatment of allergic rhinitis, which could be a contributing factor to the patient's cough 4.
- The use of macrolides such as azithromycin or clarithromycin in combination with beta-lactams may be considered for the treatment of community-acquired pneumonia, although the patient's symptoms do not currently suggest this diagnosis 5.
Potential Causes and Diagnostic Approaches
- Cough variant asthma (CVA) and PNDS are potential causes of non-productive cough, and diagnostic tests such as histamine challenge and ENT examination may be useful in identifying these conditions 2.
- The patient's lack of response to Z-pack and steroids suggests that the cough may not be related to a bacterial infection or inflammation, although further testing may be necessary to rule out these possibilities.
- A comprehensive diagnostic approach, including a thorough medical history, physical examination, and diagnostic tests, is necessary to identify the underlying cause of the patient's cough and guide treatment 2, 6.