Computed Tomographic and Magnetic Resonance Imaging Diagnosis of Concurrent Sinonasal Aspergillosis and Meningoencephalocele in a Dog.

Abstract

A 4-year-old male castrated mixed breed dog was admitted to the Veterinary Medical Center of the University of Tennessee College of Veterinary Medicine for evaluation of unilateral nasal discharge. Discharge had been present for 2 months, with progression from purulent to hemorrhagic discharge after empiric treatment by the primary veterinarian 6 weeks prior to referral. The dog had a history of seizures starting at 1 year of age that were controlled with phenobarbital. Computed tomography and magnetic resonance imaging of the head yielded diagnoses of a left-sided meningoencephalocele with extension of the olfactory bulb into the caudal nasal passage and destructive rhinitis and frontal sinusitis consistent with aspergillosis. Rhinoscopy was performed to collect diagnostic samples, debride fungal plaques, and guide clotrimazole cream application. Biopsies revealed suppurative rhinitis with abundant aspergillosis, with Aspergillus sp. confirmed on fungal culture. Postoperatively, the patient was treated with a short course of oral posaconazole. Stertorous breathing was noted 4 months following treatment. Recheck sinoscopy and rhinoscopy revealed one fungal plaque in the left nasal cavity and small, hyperemic turbinates. Treatment was repeated, resulting in resolution of clinical signs. Repeat rhinoscopy 1 month later had no evidence of residual disease. Seizures recurred 3 years after the second treatment and were medically managed by the primary care veterinarian. This case report describes a rare case of nasal aspergillosis complicated by a meningoencephalocele. Despite the large cribriform plate defect resulting in exposure of the meninges and olfactory bulb, repeated debridement and topical antifungal treatment were well tolerated by this patient. There was no recurrence in signs for 3 years, after which the dog was lost to follow-up.