What is the most likely diagnosis for a 63-year-old man with a 2-year history of productive cough, no smoking history, and previous employment in a cotton factory, presenting with vital stability and ronchi on auscultation?

Occupational Chronic Bronchitis (Byssinosis)

The most likely diagnosis is occupational chronic bronchitis, specifically byssinosis, caused by chronic cotton dust exposure in the textile factory. 1, 2

Clinical Reasoning

This patient's presentation is classic for occupational lung disease from organic dust exposure:

• 2-year history of productive cough that began precisely when he retired (suggesting symptom onset coincided with cessation of exposure, though chronic inflammation persists) 1
• Cotton factory worker for many years - cotton dust is a well-established cause of chronic bronchitis and byssinosis 1, 2
• Non-smoker - eliminates the most common cause of chronic bronchitis, making occupational exposure the primary etiology 1
• Ronchi on auscultation - consistent with chronic airway inflammation and mucus hypersecretion 1
• Productive cough "most days" - meets clinical criteria for chronic bronchitis (productive cough for at least 3 months per year for 2 consecutive years) 1

Why Not the Other Options?

Asthma (Option A) is less likely because:

• The patient lacks typical asthma features: no mention of wheezing, dyspnea, or episodic symptoms 1
• Ronchi (continuous sounds) rather than wheezes suggest chronic bronchitis rather than reversible airway obstruction 1
• While occupational asthma from cotton exposure can occur, it typically presents with variable symptoms that worsen during work exposure and improve away from work 1, 3, 4

COPD (Option B) is possible but less precise:

• In up to 15% of COPD cases, occupational exposure is the primary cause 1
• However, without pulmonary function testing showing fixed airflow obstruction, the more accurate diagnosis is occupational chronic bronchitis 1
• The distinction matters because early removal from exposure can prevent progression to fixed COPD 1

Chronic eosinophilic pneumonia (Option C) is unlikely:

• No systemic symptoms (fever, weight loss, night sweats) 1
• Would typically show peripheral eosinophilia and infiltrates on chest X-ray 1
• Not associated with cotton dust exposure 1

Chronic aspergillosis (Option D) is unlikely:

• No predisposing factors mentioned (prior TB, sarcoidosis, or cavitary lung disease) 1
• Would expect constitutional symptoms and radiographic abnormalities 1
• Not an occupational disease of textile workers 1

Key Diagnostic Features of Byssinosis

Byssinosis is recognized as occupational disease code 304.02 in European classifications, defined as "pulmonary diseases caused by inhalation of cotton, flax, hemp, jute, sisal, and bagasse dust" 2

The condition typically presents with:

• Chronic productive cough and sputum production from prolonged organic dust exposure 1
• Symptoms may persist even after exposure cessation due to established chronic airway inflammation 1
• Can progress to fixed airflow obstruction (COPD) if exposure continues 1, 2

Clinical Implications

Approximately 15% of chronic bronchitis and COPD cases are attributable to occupational exposures, yet this diagnosis is commonly missed by clinicians 1

The diagnosis is established by:

• History of cotton dust exposure in a worker without other identifiable causes of chronic cough 1
• Chronic productive cough meeting clinical criteria 1
• Exclusion of smoking and other causes 1

This patient should be evaluated for:

• Pulmonary function testing to assess for fixed airflow obstruction 1
• Consideration for workers' compensation and occupational disease recognition 2
• Bronchodilator therapy if airflow obstruction is present 1

The prognosis depends heavily on duration of exposure before diagnosis - early recognition and removal from exposure leads to better outcomes 3, 4