Bacterial Meningitis After Sinus Surgery in Five Adult Horses

OBJECTIVE: To report meningoencephalitis as a complication after paranasal sinus surgery in 5 horses. STUDY DESIGN: Case series. ANIMALS: Adult horses (n = 5). METHODS: Medical records (2005–2010) of 5 horses that developed neurologic signs after sinus surgery were reviewed to identify potential risk factors, cause(s), or common pathways for infection. RESULTS: Underlying diseases were primary (n = 1) and secondary sinusitis (4) because of apical dental infection (1), sinus cyst (2), or masses in the ethmoturbinate region (2). Horses were treated by conventional surgical approaches and aftercare including repeated sinus lavage. Four horses had undulating pyrexia postoperatively despite antimicrobial therapy. All horses developed neurologic signs, eventually unresponsive to treatment. Suppurative meningoencephalitis was diagnosed macro‐ and/or microscopically on necropsy in all horses. CONCLUSION: Meningitis is a rare but fatal complication after sinus surgery in horses.