A 45-year-old cotton textile worker presents with progressive breathlessness that is worst on Mondays (first day after weekly rest) and improves as the week continues. Spirometry shows reversible airflow obstruction. This 'Monday morning fever/tightness' pattern is pathognomonic of:
- A Occupational asthma due to isocyanates
- B Extrinsic allergic alveolitis (Farmer's lung)
- C Chronic obstructive pulmonary disease
- D Byssinosis ✓
Explanation
Byssinosis is caused by inhalation of cotton, flax, or hemp dust and is characteristically associated with chest tightness and dyspnoea worse on the first day of work after the weekend break ('Monday morning fever'), improving as the week progresses (tachyphylaxis). The causative agent is believed to be endotoxin from gram-negative bacteria contaminating the fibers and non-specific histamine release. Grading (Schilling): Grade 1/2 = Monday tightness only; Grade 1 = tightness throughout Monday; Grade 2 = tightness Monday and other days; Grade 3 = permanent disability. Occupational asthma to isocyanates (polyurethane foam) worsens with continued exposure without the Monday pattern.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.