20th February 2025

A 57-year-old man is brought to ED with worsening shortness of breath.

A 57-year-old man is brought to ED with worsening shortness of breath. 

He tells you that he is usually short of breath, particularly on exertion, but this is now much worse and he is short of breath at rest. He normally has a cough productive of black pigmented sputum which he puts down to his smoking history of 20 pack years.

His past medical history include hypertension, ischaemic heart disease and rheumatoid arthritis. He now works as a supermarket manager but previously worked in coal extraction which he gave up due to his rheumatoid arthritis.

On examination, he shows signs of respiratory distress with marked tachypnoea and use of accessory muscles. Swan neck deformity and clubbing are noted on examination of the hands.

Saturations are 90% on 60% O2. HR is 103 bpm, BP 130/87 mmHg and he is afebrile.

ABG results are as follows: pH 7.32 pO2 7.7 pCO2 6.1 HCO3 20.

CXR shows upper and midzone reticular and nodular changes with a cavity noted on the left upper zone.

Hb 120 g/L (M 130-180 g/L; F 115-165 g/L), Plt 400×10⁹ /L (150-450×10⁹ /L), WCC 11×10⁹ /L (4-11×10⁹ /L), Neut 10×10⁹ /L (1.8-7.5×10⁹ /L), Lymph 0.3×10⁹ /L (1-4×109 /L), Na 137 mmol/L (133-146 mmoL/L), K 4.4 mmol/L (3.5-5.3 mmoL/L), Urea 8.2 mmol/L (2.5-7.8 mmoL/L), Creat 130 μmol/L (M 59-104 μmol/ L; F 45-84 μmol/ L), CRP 130 mg/L (<5 mg/L).

What is the most likely diagnosis?

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