New study aims to predict lung disease in kids using biomarkers

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Age at the beginning of the study 0-17 years old * Clinical indication and qualification by the attending physician for fiberoptic bronchoscopy under general anesthesia: * Obstruction of the airways: * Suspicion of foreign body aspiration * Persistent stridor * Abnormal result of functional tests of respiratory system - flattening of inspiratory or expiratory curve, presence of restriction (tested vital capacity \<5 percentile) or irreversible obstruction (persistence of Tiffneau index \<5 percentile despite administration of bronchodilators) * Radiological findings located in the course of the larynx, trachea or bronchi * Persistent atelectasis on subsequent radiological examinations * Persistent cough \>4 weeks * Hemoptysis * Suspected laryngomalacia or tracheobronchomalacia * Suspected tracheoesophageal fistula * Persistent dyspnea unresponsive to anti-asthmatic treatment used for min. 2 months, with no other identifiable causes * Radiologically detected mediastinal abnormalities * Suspected presence of a vascular ring * Presence of excessive secretions that are impossible for the patient to expectorate * Fine needle biopsy of cystic lesions * Obtained consent from patient/legal guardian for participation in the study Exclusion Criteria: * Active acute respiratory infection up to 4 weeks before the procedure * Taking antibiotics or systemic glucocorticosteroids up to 4 weeks before the procedure * Patients with very severe comorbidities (congenital immunodeficiencies, genetic disorders, neurological or neuromuscular diseases, cancer, severe congenital heart defects, heart failure, liver failure, inflammatory bowel disease, celiac disease) * Patients with blood clotting disorders * Children with diagnosed respiratory diseases other than asthma and protracted bacterial bronchitis - including interstitial diseases, tuberculosis, inflammation of small and medium-sized blood vessels * Patients for whom \>48 hours have passed between suspicion of foreign body aspiration and interventional bronchoscopy * Children with foreign body aspiration having a foreign body located in the trachea