We have shown than topical antifungal medication with meticulous debridement results in an overall success rate for SNA in 58 of 62 (94%) dogs (J Am Vet Med Assoc 2017;250:309). It is well known, however, that fungal hyphae do not invade the mucosa but can only be found at the mucosal surface and within material collected from the nasal cavity (J Comp Pathol 2005;132:283). Consequently, meticulous debridement alone might be successful to clear SNA.

Dogs with nasal discharge were prospectively enrolled if CT and endoscopic findings were indicative of SNA and fungal culture and PCR was positive for A. fumigatus. Trephination of frontal sinus was performed if involvement was seen on CT and it could not be reached endoscopically. Fungal plaques were loosened with a curette and removed from the affected frontal sinus by suction or with flushing using copious amounts of balanced electrolyte solution (up to 5 L). If no trephination was performed, fungal plaques and necrotic material in the sinus were loosened with forceps under endoscopic guidance and then flushed out. Once there was no evidence of fungal material left in the frontal sinus, flushing and suction were continued in the nasal cavity. This procedure of flushing and suctioning, lasting up to 2 hours, was performed until all visible fungal material and necrotic tissue were removed. No antifungal drugs were used. Recheck endoscopy with sinonasal flushing was repeated 3–5 weeks later. Resolution of SNA was defined as absence of visible fungal plaques with no or negligible amounts of necrotic material present during the second flushing and no clinical signs 4 months later based on telephone communication.

So far 9 dogs were enrolled, 6 (mean 6.5 years old) with >4 months re-evaluation. 1 dog died unrelated to SNA 2 months after enrolment. Trephination was performed in 4/6 dogs. No fungal material was seen in any of the 6 dogs at the recheck endoscopy (after median 26 days) and all owners confirmed no nasal discharge at the telephone communication (after median 204 days).

This preliminary study suggests that antifungal drugs are not needed for the treatment of canine SNA if debridement is performed meticulously and absolutely all fungal material is removed.

Disclosures

No disclosures to report.