Ventricular pneumocephalus, cervical subarachnoid pneumorrhachis, and meningoencephalitis in a dog following rhinotomy for chronic fungal rhinitis.

Abstract

CASE DESCRIPTION: A 5-year-old 35.8-kg (78.8-lb) neutered male Labrador Retriever was evaluated for chronic nasal discharge associated with a fungal infection. The dog had previously been prescribed antimicrobials and antifungal treatment, but owner compliance was lacking. CLINICAL FINDINGS: Bilateral mucopurulent nasal discharge, mild ulceration of the left nasal commissure, and hyperkeratosis of the dorsal nasal planum were present. Computed tomography revealed destruction of the intranasal structures, focal lysis of the cribriform plate, and invasion of a soft-tissue mass into the frontal cortex. Rhinoscopy revealed a large pale mass in the caudal aspect of the right nasal passage; a biopsy sample was consistent with Aspergillus sp on histologic evaluation. TREATMENT AND OUTCOME: Initial treatment included medical management with an antifungal agent. Approximately 3 months later, a large fungal granuloma in the right frontal sinus was removed and debridement was performed via dorsal rhinotomy. One month after surgery, the dog was evaluated for signs of cervical pain and altered mentation. An MRI and CSF analysis were performed; diagnoses of ventricular pneumocephalus, subarachnoid pneumorrhachis, and meningoencephalitis were made. Management included oxygen therapy and administration of antimicrobials, analgesics, and antifungal medications. On follow-up 9 months after initial evaluation, neurologic deficits were reportedly resolved, and the dog was doing well. CONCLUSIONS AND CLINICAL RELEVANCE: This report emphasizes the importance of prompt, appropriate treatment of fungal rhinitis in dogs. Although rare, pneumocephalus and pneumorrhachis should be included as differential diagnoses for neurologic signs following treatment for this condition. In this dog, the complications were not considered severe and improved over time with supportive care.