Wang et al report an interesting case of systemic pyoderma gangrenosum (PG) with associated lung injury.1 They recognise the importance of excluding Wegener's granulomatosis (WG) in patients with respiratory symptoms and cutaneous ulceration, but in their case seem only to have done this on clinical and histopathological grounds. A more complete assessment should include testing for cANCA and anti-proteinase 3 (PR3).2

We are currently treating a 54 year old ex-smoker who presented for investigation of haemoptysis and who subsequently developed episcleritis and skin lesions resembling PG. Initial investigations were Hb 11.3 g/dl, WBC 9.4 × 10⁹/l, platelets 401 × 10⁹/l, ESR 86 mm/h, and CRP 181 mg/l. Renal function was normal. The chest radiograph showed alveolar shadowing in the …