Pigeon Breeder's Disease: A Paradigm for Understanding Hypersensitivity Pneumonitis

摘要

Pigeon breeder's disease is a form of hypersensitivity pneumoni-tis induced by the inhalation of avian antigens that may derive from pigeons, budgerigars, parakeets, canaries, and less frequently, chickens, ducks, and turkeys. Patients may develop an acute lung reaction with an influenza-like syndrome or a chronic interstitial lung disease, with progressive dyspnea, restrictive functional impairment, and rest hypoxemia that worsens with exercise. Bronchoalveolar lavage is mainly characterized by an increase in the percentage of T lymphocytes, with a strong predominance of CD8+ T cell subset. There are no single pathogno-monic features for the diagnosis, so this is usually made from a combination of a high degree of clinical suspicion with a careful environmental history and the conjunction of symptoms, physical findings, imaging, physiologic and immunologic abnormalities, and cellular bronchoalveolar lavage profile. In chronic pigeon breeder's disease, lung biopsy is recommended for diagnosis because the behavior of the disease is similar to many other interstitial lung diseases. Avoiding exposure to the avian antigen and using corticosteroids to downregulate alveolitis are the main therapeutic approaches.