Constrictive bronchiolitis is characterized by a fibrosing inflammatory process that surrounds rather than fills airways lumen, resulting in hyperinsufflation. HRCT demonstrates mosaic areas of decreased attenuation and vascularity and evidence of air-trapping. The disease is poorly responsive to steroids and adrenergics bronchodilators. Tiotropium bromide is a synthetic quaternary anticholinergic agent that is functionally selective for specific muscarinic receptors that mediate airway smooth-muscle contraction, and has an extremely long duration of action.
Six patients, 3 female, mean age 54.8y (±8.7)nonsmonkers, with clinical, HRCT and functional diagnosis of constrictive bronchiolitis, with lung biopsy in 4, were submitted to a trial of once-daily inhalation of tiotropium (18 mcg).
Spirometry was performed before and 21 days after the medicationThe initial spirometry showed a an obstructive pattern (mean±SD): FVC=1.3±0.3L and FEV1=0.74±0.3L. After 21 days of tiotropium, in all patients the FVC improve more than 10%. Mean FVC also significatively improve (1.65±0.4, p=0.004), but not the FEV1 (0.91±0.4).
In spite of fibrosing predominance in constrictive bronchiolitis, we observed a significant improvement of pulmonary function after 21 days of tiotropium.
The influence of this finding on the evolution of the disease needs further investigation.
Ronaldo Kairalla, None.