Case 11: Asthmatic male with cough

History A male aged 58 years, weight 56 kg, body mass index (BMI) 22 (ideal range, 18.9-25), has had mild asthma for many years controlled by inhaled steroids and bronchodilators. Following an upper respiratory tract infection, he develops a cough with purulent sputum. His GP arranges his admission to hospital, largely because of his confused state.