UPPER AND LOWER AIRWAY INFLAMMATION IN HORSES: ENDOSCOPIC SCORING, DIAGNOSIS AND TREATMENT

摘要

Endoscopy is often used in equine medicine to investigate respiratory disorders. Upper and lower airways are both integral parts of the respiratory tract and human studies brought the concept of "one airway, one disease".1 Indeed, there is evidence that allergic rhinitis and sinusitis co-exist in a high proportion of patients with asthma and chronic obstructive pulmonary disease (COPD).2 Based on these findings, the World Health Organization (WHO) published recommendations for physicians to assess the lower airway condition in patients with rhinitis and conversely to perform upper airway evaluation in patients with asthma.3 To the contrary, there is evidence in equine medicine that pharyngeal inflammation is not associated 1) with changes in tracheal cytology4, or 2) with BAL cytology when done in a small number of 18-month-old healthy horses with low mucus scores.5 Since upper airway endoscopy is routinely performed by equine practitioners, we will assess if the finding of upper airway inflammation also suggests the presence of lower airway inflammation in a patient, thus indicating the utility of further diagnostic tests. We will also review the diagnostic tests available to diagnose non-infectious airway inflammatory pathologies. Lastly, we will review the treatment options available once a diagnosis of airway inflammation is established.