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.

Objectives:

The aim of this study is the characterization of patients with bronchiolitis obliterans in terms of lung function, bronchial hyperreactivity and the degree of the systemic and bronchial inflammation.

Sputum and serum samples are analyzed by quantitative real-time polymerase chain reaction (PCR) (qRT-PCR) and by cytometric bead assay (CBA). Components of the innate immune system (mannose-binding protein, TLR recognition proteins and surfactant proteins) are genetically determined from sputum or blood respectively. In the conduct of this study the investigators will retrospectively and systematically evaluate the available high-resolution computed tomography (HRCT) studies of affected patients

Methods and Work Programme:

This study consists of two study visits (V1 and V2)

V1:

• Measurement of nitric oxide in expired air (eNO)
• Measurement of carbon monoxide in the exhaled air (eCO)
• Lung function testing with spirometry and body plethysmography
• Blood test: blood count, CRP, RAST, serum inflammatory mediators, genetic markers of the non-specific pulmonary defense system
• Induced sputum for inflammatory mediators and microbiological investigations

V2:

• Unspecific bronchial provocation test with methacholine (PD20 FEV1 methacholine)

Study population:

Children and young people (6 - 25 years of age). Both the patients and the healthy subjects are recruited from the outpatient clinic of Pediatric Allergy and Pulmonology.

Inclusion Criteria:

• informed consent
• between 6 and 25 years of age
• Known bronchiolitis obliterans / no bronchiolitis obliterans(depending on the study group)
• Ability to perform lung function tests and inhalation

Exclusion Criteria:

• <6 and > 25 years of age on the day of written informed consent
• Acute illness with systemic or bronchial inflammation
• every chronic condition or infection (eg HIV, tuberculosis, malignancy)
• pregnancy
• known alcohol and/ or drug abuse
• Inability to understand the extent and scope of the study
• Participation in another study

The study is carried out in children and young adults (6 to 25 years). Both the patients (20) and the healthy subjects (20) are recruited from the outpatient clinic of the departement of Pediatric Allergy and Pulmonology, University Clinic, JW Goethe University, Frankfurt/M, Germany.