Empyema of the guttural pouch (auditory tube diverticulum) in horses: 91 cases (1977-1997)

Objective-To identify features of guttural pouch (auditory tube diverticulu m) empyema in horses and compare findings of uncomplicated guttural pouch e mpyema with guttural pouch empyema complicated by chondroids. Design-Retrospective study. Animals-91 horses with guttural pouch empyema; Procedure-Medical records of horses with guttural pouch empyema were review ed. Results-The most common owner complaint and abnormal finding was persistent nasal discharge. Chondroids were detected in 21% (19/91) of affected horse s. Streptococcus equi was isolated from the guttural pouch in 14 of 44 hors es; for Streptococcus spp, in vitro resistance to sulfadimethoxine and trim ethoprim-sulfamethoxazole was detected. Retropharyngeal swelling and pharyn geal narrowing were significantly more prevalent in horses with chondroids, compared with horses with uncomplicated empyema. Ninety-three percent of a ffected horses were discharged from the hospital; at time of discharge, 66% had complete resolution of disease, 19% had improvement without resolution , and 15% did not have improvement. Conclusions and Clinical Relevance-Horses with persistent nasal discharge s hould be examined endoscopically for guttural pouch empyema. Treatment with ravage offers a good prognosis for resolution of uncomplicated guttural po uch empyema. Aggressive treatment with lavage and endoscopic snare removal of chondroids offers a good prognosis and may make surgical intervention un necessary.