Dear Dr. Thompson: We have a 7-year-old golden retriever that has started having the occasional nosebleed. Sometimes she has sneezing spells and will spray some blood on the floor. She is eating, drinking, and acting fine. Is it the dry air from the air conditioning or should we be worried?
The vast majority of the time in dogs, a bloody nose is a sign of something more serious lurking inside the nasal cavity. Occasionally, one of the problems can be an underlying cause of nasal bleeding, called epistaxis, from the body's inability to normally clot blood. Blood tests to check the clotting factors would easily detect most problems. If it is not a clotting disorder, the process gets more complicated.
A little background on the anatomy of a dog's sinus cavity will help to explain why getting an accurate diagnosis can be very difficult with these symptoms. Dogs have large, elaborate winding bones and multiple sinus cavities in the snout and over the eyes. This partially contributes to their amazing sense of smell but only a tiny fraction is visible and accessible to determine the source of the bleeding.
As a result of lots of sniffing and exploring, occasionally a foreign body is snorted up into the sinuses. This will cause local irritation and might lead to some bleeding. More commonly a concurrent infection will be present and bleeding would rarely be the only sign. I had one patient that had a large blade of grass up his nose that he sneezed out in the exam room three weeks later after repeated treatment for sinus infections.
Fungal infections are rare in our area, but they can affect the sinuses in dogs and bleeding may be the only sign. There are blood tests for antibodies to the fungus, but they can miss active infections. A small scope can be passed in some larger breeds of dogs to visualize characteristic thickenings of the lining of the sinuses, but remember that a significant portion of the cavity is not accessible and could easily be missed. Often response to treatment with antifungal medications might be the only way to solve the problem. These are not without side effects and some testing is needed to make sure no secondary issues develop.
Unfortunately, in a dog her age cancer has to be high on the list of considerations. These tumors will grow silently for long periods of time and the occasional nosebleed might be the only outward symptom. X-rays of the skull might detect more aggressive tumors, but this is not a very sensitive test and many times the tumor will not be seen. A CT, or CAT scan, is the best test to evaluate the bones of the sinuses, but it is an expensive test that would require a trip to a specialty center.
Hopefully, her problem is relatively simple, easily diagnosed and cured. I would suggest having her evaluated right away because recurring nosebleeds are rarely benign.
Questions for Dr. Gary Thompson can be emailed to firstname.lastname@example.org 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.