Chronic Cough Diagnostic Differential Diagnosis
Single Most Likely Diagnosis
- Gastroesophageal Reflux Disease (GERD): This is often considered the most likely diagnosis for chronic cough due to its high prevalence and the fact that cough can be the sole presenting symptom of GERD. The mechanism involves acid reflux irritating the upper airway, triggering a cough.
Other Likely Diagnoses
- Asthma: Asthma is a common cause of chronic cough, especially in individuals with a history of atopy or allergic rhinitis. Cough can be the predominant symptom, especially in cough-variant asthma.
- Chronic Obstructive Pulmonary Disease (COPD): COPD is another likely cause, particularly in smokers or those with a history of smoking. Chronic cough is often accompanied by sputum production.
- Postnasal Drip (Upper Airway Secretion Syndrome): This condition, often due to allergic rhinitis or sinusitis, can cause a chronic cough due to the irritation of the upper airway by secretions.
Do Not Miss Diagnoses
- Lung Cancer: Although less common, lung cancer can present with a chronic cough and is critical to diagnose early. Risk factors include smoking and exposure to carcinogens.
- Tuberculosis (TB): TB is a serious infection that can cause chronic cough, often accompanied by systemic symptoms like fever, night sweats, and weight loss. It's crucial to consider, especially in high-risk populations.
- Pulmonary Embolism: While typically presenting acutely, chronic or recurrent pulmonary emboli can cause a chronic cough. This diagnosis is critical due to its high mortality rate if untreated.
Rare Diagnoses
- Bronchiectasis: A condition characterized by permanent dilation of parts of the airways, leading to chronic cough and sputum production. It's less common but should be considered in patients with recurrent infections or specific risk factors.
- Cystic Fibrosis: Although primarily diagnosed in childhood, some cases of cystic fibrosis may not be diagnosed until adulthood, presenting with chronic cough among other symptoms.
- Sarcoidosis: An autoimmune disease that can affect the lungs, causing chronic cough, among other symptoms. It's less common but important to consider in the differential diagnosis of chronic cough.