Equine Asthma Syndrome
DOI:
https://doi.org/10.30972/vet.3628429Keywords:
Equine, Asthma, Infammation, AirwaysAbstract
Equine Asthma Syndrome (EAS) is a recently adopted term that encompasses chronic, non infectious inflammatory conditions of the lower airways. It facilitates the recognition of shared phenotypic features among these disorders, including airway hyperresponsiveness, bronchospasm, inflammatory cell infiltration, increased mucus production with altered viscoelastic properties, and progressive airway remodeling over time. This terminology provides a broad phenotypic framework that enables subcategorization of the disease based on severity, according to clinical presentation (presence or absence of respiratory effort at rest), triggering factors (barn versus pasture exposure) and supporting diagnostic tests such as endoscopic findings and bronchoalveolar lavage cytology. In this way, two subtypes of asthma are defined, mild to moderate asthma (formerly known as Inflammatory Airway Disease) and severe asthma (formerly known as Recurrent Airway Obstruction). Although the pathogenesis is not yet fully understood, stable housing is recognized as the primary risk factor, as affected horses are potentially exposed to high concentrations of organic and inorganic airborne particles, as well as noxious gases. Treatment focuses on minimizing exposure to airborne dust through environmental management, combined with pharmacological therapy aimed at reducing inflammation and bronchospasm with corticosteroids and bronchodilators
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