Dr Michael Porter DVM
Fungal Plaque in a Horse
A 7 year-old gelding presented to PHD veterinary services for the complaint of mild epistaxis (bloody nasal discharge). Endoscopic exam of the nasal passages identified a golden colored mass (Figure 1) that was covered in blood and was located within the opening to the ethmoid turbinates. The mass was diagnosed as an ethmoid hematoma based on location, appearance, and behavior. The client was given the option of surgical removal or treatment with intra-lesional doses of formalin. Based on the relatively small size of the ethmoid hematoma it was decided to attempt treating 1-2x with formalin and if there was not complete resolution then surgical resection would be pursued.
Four weeks after the first injection of formalin, a follow-up endoscopy noted significant reduction in the size of the ethmoid hematoma (Figure 2) and what appeared to be a second mass deeper within the ethmoid turbinates. The second ethmoid hematoma was not visualized during the initial exam because the first ethmoid hematoma was blocking the view! Based on these findings, the second ethmoid hematoma was injected with formalin in a similar fashion as the original ethmoid hematoma.
Six weeks after the second formalin injection the client reported that there was a slight yet persistent bloody discharge from the affected nares. Endoscopic exam revealed what appears to be a fungal plaque (black/white/yellow) adhered to the site of the ethmoid hematoma (Figure 3 and 4). This is an unusual finding and may prove to be a challenging complication. Fungal plaques have a predilection for vascular tissue and can infect the upper airway of horses. Fungal infection within the guttural pouch of a horse is well documented and can result in a catastrophic hemorrhage if not diagnosed and treated early. Fungal infection within the ethmoid turbinates is not common in my experience. Often these fungal plaques do NOT respond to systemic anti-fungal medication and must be either removed or treated aggressively with topical medication.
The current clinical plan for this horse is medication with oral anti-fungal medication for several weeks. If there is no change, the fungal plaques will be treated with topical anti-fungal medication. Stay tuned....
Finally after 4 weeks of anti-fungal medication, there is no evidence of a fungal plaque and there is NO evidence of an ethmoid hematoma (Figure 5). The ethmoid turbinates are visible for the first time in this horse since the initial exam. Although there is no evidence of an existing ethmoid hematoma, these tumors commonly reoccur hence the gelding will be monitored closely for the next 12 months.