Throat Problems in Cats

Hoarseness in cat

Question: Dear Dr. Richards,

I have a 10 year old neutered male cat, who has been a 100% indoor cat in a multi-cat household since I found him at about 7 weeks old on the streets of a large city in Malaysia.

For the last six months or so, Fritz has been having recurring bouts of hoarseness. The first time this happened, he sneezed and even coughed a little. It took 2 rounds of antibiotics (amoxicillan, I think) to clear this up. He was fine for a couple of months, then he was hoarse again, more antibiotics, then okay.

His vet said that he had an upper respiratory infection, and when I had him in for the 3rd one, she said that, unfortunately, once a cat starts having these infections, they can recur pretty frequently. After having arranged for antibiotics over the phone when the 2nd infection occurred, I took him in on the 3rd one because he passed a soft, clay colored stool that had what looked like a string of blood mixed with mucous. The vet said upper respiratory infections can sometimes cause intestinal distress.

About 4 weeks ago, I noticed he was hoarse again, and that he was spending a little more time than usual to himself, which was what he had done before. It had been maybe 2 months since his last infection. I called the vet and she prescribed antibiotics and said it wasn't necessary to see him. There were a couple of softish stools in the litter box, but it was impossible to assign ownership since I hadn't seen which cat (of 9) had passed it.

This past weekend, Fritz was hoarse on and off again, and so I called the vet this morning for advice and she asked me to bring him in this week for a CBC.

His appetite, which fell off just a little with the first infection, has been fine and his weight is stable. He remains very affectionate and can be induced to play, even now when he is hoarse, though his tendency is to sleep a little more and away from the crowd when an episode is coming on.

Up until a couple of years ago, he had recurrent conjunctivitis, mainly in the winter, but a few applications of some opthamic ointment and/or sterile drops always cleared this up within a couple of days. He hasn't had any eye problems in probably 18 months.

What would you say about a cat like this? I will of course have the CBC done, but I was wondering what this could possibly show. I guess I'm just looking for an overview of the range of potential causes and, of course, treatments for a cat showing these symptoms.

Thanks, Nancy

Answer: Nancy-

There are several possible problems that might lead to hoarseness such as you describe.

Given the past history of recurrent conjunctivitis and the response to antibiotics, a very likely possibility would be chronic herpes virus infection that has has caused nasal turbinate damage, allowing infections to easily occur in his upper airways and to cause inflammation leading to hoarseness. Most cats with this problem have nasal discharges and sneezing is also common. In severe cases nosebleeds sometimes occur. We have the best luck currently in treating these problems using azithromycin (Zithromax Rx). However, since prior antibiotic therapy has been successful it seems reasonable and probably best to stick with the antibiotics that are working.

Squamous cell carinoma and other tumors that can occur in the oral cavity and nasal passages can also lead to hoarseness. In this case, the most likely scenario would be a cancer in the pharyngeal or laryngeal region leading to the hoase sounds. The only way that I know of to check for this possibility is to anesthetize the cat and look for evidence of the tumor visually. Doing this would also help to eliminate the possibility of a benign polyp being present, as these are also somewhat common in cats and can lead to hoarseness, sneezing, coughing and/or persistent ear infections.

Hyperthyroidism causes some cats to have a hoarse meow but it usually causes weight loss even though the appetite is the same or increased. If you start to see signs of weight loss over time it would be a good idea to consider this possibility. It is relatively easy to test for since most cats have elevated T4 levels (thyroid hormone) in their blood.

Laryngeal paralysis can occur in cats. This is a condition in which the folds of the larynx which should pull back to allow the larynx to open during breathing do not do so. This condition is diagnosed by visualization of the larynx under anesthesia, so it is best to check for this while checking for polyps and cancers. I can't recall seeing a case of laryngeal paralysis in a cat so I think it is pretty rare but that it has to be considered in the list of possible problems.

Rabies can cause hoarseness, probably due to laryngeal paralysis. This would be a very unlikely diagnosis in most cases but if there is any chance of exposure to a rabid animal it also has to be considered in the list of possible causes of hoarseness in a cat.

There would also be a possibility of an oral, pharyngeal or nasal foreign body leading to infection or inflammation causing the sneezing and hoarseness. This is not too likely with a long history of problems but it is something else that occasionally causes these problems. It often takes examination under anesthesia to find these, so it is another thing to think about it you and your vet decide on an examination under anesthesia as a necessary diagnostic step.

I can not think of a relationship between any of these problems and the soft stools, except that antibiotic use can sometimes cause soft stools or diarrhea. Hyperthyroidism sometimes causes vomiting or diarrhea so I guess it could conceivably cause other stool changes. It may be necessary to think of these as separate problems, if it seems necessary to try to figure out what is going on with the stool as time goes on.

These are the things that I can think of that might lead to the signs you are seeing. By far the most common is the chronic herpes virus causing secondary bacterial infections. I am not aware of any way to prevent these from recurring. It might be helpful to add l-lysine, 500mg/day to your cat's diet but that probably won't stop the problems. Intermittent, or even chronic antibiotic use is often necessary to provide comfort if this is the problem.

Good luck with this.

Mike Richards, DVM 7/2/2001

Swallowing problems - unreadable biopsy

Question: My cat has swallowing problems and I was referred to a specialist to have them look down her throat with special instruments tiny enough to fit down a cat's throat. The specialist said if they found anything, they would biopsy it and see if it was cancer. They did the procedure, took a biopsy and the biopsy came back unreadable. The specialist says that happens sometimes. Is that true? Or does that mean the specialist messed up somehow? The specialist charged me full price for the procedure and the biopsy even though they told me absolutely nothing. I paid hundreds of dollars to find out no more than I did than when I walked through the door. I agreed that I should pay for the procedure but felt that I shouldn't have to pay for the biopsy because it came back unreadable. They eventually gave me $40 off the cost of the biopsy but let me know they were doing me a "favor" since biopsies don't always come back with a result. (By the way, they supposedly found a spot that the specialist said looked like cancer and probably was cancer and said she probably wouldn't live much longer. That was over 6 months ago and my cat seems to be fine other than swallowing with a little gulp sound).

Answer: I think that it isn't all that uncommon for some of the biopsy samples from intestinal biopsy to be damaged during the process of taking them, getting them out of the body and into a fixative or during the process of preparing them at the lab. There is a good chance that there was no fault on the part of the specialist.

I do not do endoscopy but I have been to a couple of seminars on it and the presenters always take pains to recommend multiple biopsies of suspicious sites to try to minimize this problem. This works as long as the suspect area isn't about the size of one biopsy sample. If cancer is present, it seems likely that it would be possible to get an additional sample of it at a later date. I am not sure it is possible to diagnose specific cancers by visual exam in any area of the body, so if cancer is present it would still be a good idea to get a sample and have it examined by a pathologist so that the specific type of cancer can be recognized and a plan made based on this knowledge.

Do you know if your vet examined the nasal passages, to the extent that is possible, with the endoscope during this exam? Nasal polyps sometimes cause blockages in the pharyngeal region that would produce the sounds you are hearing on swallowing. It is sometimes possible to see these without an endoscope and it may be worth asking your vet to anesthetize your cat and take a close look at this region before considering a return trip to the specialist or to another specialist is you remain unhappy with the one you went to previously. A nasal polyp is usually reasonably easy to remove and can provide a lot of comfort or even save a cat's life. Of course, there are other possible problems but this is one where a recheck could make a big difference.

I wish that you had gotten better results from the first attempt at endoscopy. It always makes it hard to recommend doing it again when that happens. But the bottom line is that sometimes that is the best thing for the patient. If the breathing/swallowing problem is worrisome, or particularly if it gets worse, some sort of further exam would be a good idea and doing endoscopy again may be necessary to get a diagnosis.

Good luck with this.

Mike Richards, DVM 3/24/2000