Diagnosis and Treatment of Canine Sinonasal Aspergillosis

Patient Overview

Barney, an 8-year-old neutered male Golden Retriever, came to East Kent Veterinary Referrals for further investigation of persistent right-sided nasal signs.

His history included ongoing unilateral nasal discharge, sneezing and intermittent epistaxis. These signs raised concern for significant underlying nasal disease, with possible causes including inflammatory rhinitis, foreign material, fungal disease, dental-related disease or neoplasia.

Given the chronicity and one-sided nature of Barney’s signs, advanced imaging and endoscopic assessment were recommended to reach a diagnosis and plan appropriate treatment.

Initial Presentation

At referral, the priority was to understand the extent and cause of Barney’s nasal disease. Unilateral nasal discharge, particularly when persistent or associated with bleeding, often warrants further investigation beyond routine medical treatment.

Barney’s case was approached in a structured way, with the referral team reviewing his history, discussing the possible causes with his owners, and planning investigations that would provide both diagnostic information and, where possible, allow treatment during the same anaesthetic.

Diagnostic Assessment and Planning

Barney underwent CT of the head under general anaesthesia. CT is particularly useful in chronic nasal disease because it allows detailed assessment of the nasal passages, turbinates, sinuses and surrounding bony structures.

In Barney’s case, CT identified destructive change within the right nasal cavity and involvement of the right frontal sinus. Importantly, the initial assessment did not identify evidence of cribriform plate destruction, which helped guide treatment planning.

Rhinoscopy was then performed to directly assess the nasal passages. Rhinoscopy allows visualisation of the nasal cavity using a small camera, and can help identify material such as fungal plaques, abnormal tissue or foreign bodies. In Barney’s case, the findings were consistent with sinonasal aspergillosis, a fungal infection that can cause turbinate destruction, discharge, discomfort and bleeding.

Samples were taken to support the diagnosis, and topical antifungal treatment was planned.

Surgery and Procedure

Barney initially underwent rhinoscopic-assisted antifungal treatment. Clotrimazole, a topical antifungal medication, was applied to the affected right nasal passages and frontal sinus region.

His owners were advised that sinonasal aspergillosis can sometimes require more than one treatment, particularly when the frontal sinus is involved. This was an important part of the initial discussion, helping set realistic expectations while still providing a clear treatment plan.

Following partial improvement but persistence of clinical signs, Barney was reassessed. Repeat rhinoscopy showed improvement in the fungal plaque burden, but ongoing disease within the right frontal sinus remained a concern.

The team then discussed a more direct approach with Barney’s owners: right frontal sinus trephination. This involves creating a small, controlled opening into the frontal sinus, allowing antifungal medication to be delivered directly into the affected sinus. This approach was selected to improve contact between the antifungal treatment and the area of persistent disease.

Barney recovered uneventfully from his procedures and was discharged the same day with pain relief, anti-inflammatory medication and detailed home-care advice.

Recovery and Post-Operative Support

Barney’s recovery was supported through clear communication with both his owners and his referring practice. Post-operative instructions covered wound care, monitoring for nasal discharge or bleeding, medication, exercise restriction and when to seek advice.

Follow-up was shared between the referral team and the referring vets, with wound checks and suture removal arranged locally where appropriate. This helped maintain continuity of care while ensuring Barney remained under referral oversight for his sinonasal disease.

At review, Barney’s owners reported steady improvement in his nasal discharge, sneezing and general demeanour. His trephination site healed well, and repeat CT and rhinoscopy were discussed as options to assess for complete resolution if clinically indicated.

When signs later recurred, the case was reassessed and further treatment was planned. This was framed as recognised disease behaviour rather than an unexpected complication. Some dogs with sinonasal aspergillosis, especially where frontal sinus involvement is present, require staged or repeated topical therapy.

Discussion

Barney’s case highlights several important considerations for referring vets managing chronic unilateral nasal disease.

Firstly, CT and rhinoscopy are complementary. CT helps define the extent of disease, including sinus involvement and bony change, while rhinoscopy allows direct visual assessment and sampling. Together, they can help differentiate fungal rhinitis from other important causes of unilateral nasal discharge and epistaxis.

Secondly, sinonasal aspergillosis can be a persistent condition. A single topical treatment may be sufficient in some cases, but repeat treatment is sometimes required, particularly when disease extends into the frontal sinus. Discussing this early with owners helps them understand the likely pathway and reduces uncertainty if further procedures become necessary.

Thirdly, the delivery route matters. Rhinoscopic-assisted treatment can be appropriate initially, but sinus trephination may provide better access where the frontal sinus remains involved. In Barney’s case, treatment was adapted according to his clinical response and the anatomical distribution of disease.

Finally, the case demonstrates the value of a collaborative referral approach. Barney’s referring vets remained closely involved, while the referral team provided advanced imaging, endoscopic assessment, treatment planning and ongoing review.

Outcome

Barney showed significant clinical improvement following combined topical antifungal treatment and sinus trephination. At later reassessment, his nasal discharge and epistaxis had improved markedly, frontal sinus palpation was comfortable, and nasal airflow was improved.

His case was managed as a staged referral journey, with treatment decisions guided by imaging, rhinoscopic findings, owner discussion and clinical response.