An easily overlooked cause of chronic lung disease
A 45 year old woman who did not work presented with a week's history of worsening breathlessness and productive cough. She was unable to complete sentences and her respiratory rate was 28 breaths/min, pulse 110 beats/min, and oxygen saturation 80% on air. She was too breathless for peak expiratory flow measurements. She had been treated for asthma for 12 years and was prescribed inhaled salbutamol and salmeterol and oral montelukast. This was her first hospital admission. She had smoked five cigarettes a day for 25 years.
On examination, she had finger clubbing and was cyanosed. Her chest was hyperexpanded and hyper-resonant to percussion. Widespread panexpiratory wheeze and inspiratory crepitations were audible. Chest radiography showed peribronchial thickening. Acute asthma was diagnosed, and she was managed accordingly. Once stable, concerns were raised about this diagnosis. Further history included longstanding breathlessness and recurrent respiratory infections. Lung function tests showed an obstructive defect (her