Isolated tracheobronchial inflammation with airway obstruction: a diagnostic challenge

A 56-year-old previously healthy male gymnast presented with a 2-month dry cough and a 1-month intermittent fever.He had voice hoarseness from a vocal cord polyp diagnosed 20 years ago.At a previous hospital, a chest computed tomography (CT) scan showed sparse basal fibrosis, and laboratory tests indicated high inflammatory markers, with microbiological cultures and polymerase chain reaction for respiratory pathogens yielding negative results.Bronchioalveolar lavage revealed neutrophilic infiltration.He was empirically treated with broad-spectrum antibiotics due to persistent fever; he initially responded but relapsed after SARS-CoV-2 infection, treated with remdesivir and dexamethasone, although with mild symptoms, with transient fever relief.After discharge, the fever reoccurred.A repeat chest CT showed diffuse thickening of the tracheal and bronchial walls.Fluorine-18 fluorodeoxyglucose positron emission tomography -CT (F-FDG PET-CT) demonstrated uptake along the trachea and main bronchi, sparing the posterior tracheal circumference, with mild hypermetabolic mediastinal lymph nodes (Fig , A-C).Bronchoscopy revealed diffuse nodular thickening, oedema of the tracheal and bronchial mucosa, an enlarged main carina, and an anterior laryngeal polyp (Fig, D-E).Bronchial and tracheal biopsies revealed mild fibrosis, chronic inflammation, and a few neutrophils (consistent with nonspecific chronic bronchitis).Serology for ANA (Antinuclear Antibodies), ENA