While nasal and sinus problems are common in people, they are generally more of a nuisance rather than a serious health concern. However, in dogs and cats conditions affecting the sinus cavity are infrequently seen and can be associated with some challenging diseases.
Clear discharge from your pet’s nose can be normal, but if that drainage is yellow or bloody it can signal a disease process.
Bloody noses are a common occurrence for some people, but bleeding from your pet’s nose is never normal. In older dogs it may be a symptom of a tumor growing up in the nasal passages. Given how extensive a dog’s sinus cavity can be, diagnosis can be a challenge. Rarely will a simple x-ray be adequate to determine the source of the bloody nose. A CT scan or a procedure called rhinoscopy where a rigid fiberoptic scope is passed up into the sinuses under general anesthesia may be needed.
Rhinoscopy can also allow for direct visualization of the lining of the sinuses and many times a biopsy can be collected. A CT scan can evaluate how the underlying bones of the skull are affected and how extensively a growth may have invaded the surrounding tissues. With the exception of tumors near the very front of the sinus cavity, surgical excision is nearly impossible but some can be successfully treated with radiation therapy.
Fungal infections of the sinuses in dogs and cats can occasionally be associated with chronic sinus discharge. These fungal organisms establish themselves up in the nasal cavity and often the main outward symptom is chronic recurring secondary bacterial infections. Chronic infections can cause erosions that bleed intermittently. These fungal infections can cause a characteristic plaque formation up in the sinuses that can be found on rhinoscopy, but generally blood tests or testing of fluid from the sinuses can be used to detect parts of the fungi. Treatment can be challenging but with long term antifungal medications many can be successfully managed.
Cats frequently develop benign nasal polyps that can extend down the small tube that connects the sinuses to the inner ear or into the back of throat. Sometimes the only sign of nasal polyps may be recurring ear infections. These polyps can be shockingly large relative to the small spaces they inhabit and surgical removal may temporarily resolve the symptoms. Some polyps can be easily removed under a short general anesthesia procedure but chronic polyps that invade a structure of the inner ear called the tympanic bulla can require a more extensive surgery.
Dogs can acquire a nasal mite that lives on the mucous membranes of the sinuses. This mite can be a source of a mild, chronic drainage and sneezing can be a nuisance for owners and dogs alike. These mites can only be seen via magnification during rhinoscopy, but many times treatment with an anti-parasitic medication called ivermectin will clear the infection and may be attempted to see if symptoms resolve.
The good news is these mites only infect dogs and can’t be transmitted to people. If your pet is experience chronic or recurring sinus infections or bloody noses, call your veterinarian right away. An early and accurate diagnosis can make treatment easier.
Questions for Dr. Gary Thompson can be emailed to askthevet@theblade.com or mailed to The Blade, Attn. Ask the Vet, 541 N. Superior St. Toledo, OH., 43660. Dr. Thompson regrets that he cannot answer individual letters.
First Published July 25, 2021, 1:00 p.m.
