We thank Joob and Wiwanitkit for their interest in our article[12]. Careful history taking and examination should always form part of the initial assessment of suspected vasculitis, as large vessel vasculitis limited to the pulmonary arteries is likely to be a rare entity and both patients described went on to develop asymptomatic aortitis. Radiographic features that may help distinguish large vessel pulmonary vasculitis from CTEPH in CT pulmonary angiography have been described;[3] as Joob and Wiwanitkit highlight the key to identifying large vessel pulmonary vasculitis for it to be considered in the initial differential diagnosis. In countries with a higher incidence of large vessel vasculitis such as Japan the diagnosis is sometimes made using the combination of laboratory data, radiographic findings and HLA associations,[4] although the validity of this approach to European patients is unclear.