The aim of this case-control study is the characterization of the bronchial and systemic
inflammation of children and young adults with bronchiolitis obliterans.
On the first visit subjects are asked to perform a lung function test (spirometry, body
plethysmography with helium). Further levels of eNO and eCO are determined. A blood sample is
drawn to describe the inflammatory status. Bronchial inflammation will be measured in induced
sputum. At the second visit, a non-specific bronchial provocation testing (PD20 FEV1
methacholine) is performed.