Question : We have a 12 year old tortoise shell cat. Never gets sick and always very lively. Enjoys going outside during the day and always stays in yard and comes inside at night. Since last night she has lost her meow (growl, with this tortie). She sounds like someone with a sore throat. Breathing is alittle off and she sounds seriously congested all of the sudden. Only thing new in the house is a 10 week old pure bred siamese kitten. And she is definately getting sluggish. We will take her to hospital here in Boston if this persists. But what could be wrong?
Answer :
Hello,
I am sorry your kitty is not feeling well. Because of her age, I am concerned about systemic illnesses like diabetes, kidney disease and hyperthyroidism. Hyperthyroidism is most commonly associated with loss of voice, or hoarseness. Because cats are so adept at hiding signs of illness, they can appear to be the picture of health one day, and very sick the next. Because the new kitten in the house, your older kitty may also have developed an upper respiratory infection, which is very likely given the congestion. An upper respiratory infection can be pretty serious if not treated quickly, because when a kitty becomes congested enough that they cannot smell their food, they will not eat. Please see the following website for more information on upper respiratory infection.
http://www.veterinarypartner.com/Content.plx?P=A&S=0&C=0&A=613
Just in case, here is some information on hyperthyroidism as well.
http://www.veterinarypartner.com/Content.plx?P=A&S=0&C=0&A=516
Even though your kitty is not in a crisis, I worry that she will feel progressively worse as the day goes on. You can keep an eye on her and have her seen by her vet in the morning, and if she gets into trouble, you can have her seen by the nearest emergency vet. In an effort to help clear the congestion, you can run a hot shower and sit with her in the bathroom for 10 minutes several times a day. Make sure she doesn’t get into the tub and get scalded. The steam will help clear the nasal passages and hopefully allow her to sneeze some congestion out. Please let me know if I can be of further assistance. If this has been helpful, please hit the green accept button. Best of luck with your kitty, I hope she feels better soon 
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$18 : We have a 12 year old tortoise shell cat. Never gets sick