UTI?

Question
Hello!
I am contacting you because my dog recently started displaying symptoms of what I think might be a UTI.  

about 3 days ago my female dog of about 15 months started licking herself a lot more than usual.  I noticed that her vulva was swollen, not immensely, but definitely swollen. It now seems to be less swollen, but still bothering her.  She seemed to be displaying symptoms of being in heat, but she is spayed.  After doing some research it looked as though she may have a UTI or vaginitis or both, or maybe something completely different.

She is eating and drinking normally, and is not asking to go out or peeing more than usual.  She also doesn't seem to have trouble urinating or painful urination.  There is no vaginal discharge at all from what I have been able to tell.  There also doesn't appear to be any irritation around the vaginal area other than some very minor redness, which I presume is from all the licking.  So the only real symptom seems to be a slightly swollen vulva which is causing her discomfort.  She is constantly stopping to lick herself, and seems somewhat bothered by it, but at the same time maintains her energy and excitement to play, and immense drive for food.  

So far all I have been doing to treat this is adding some braggs ACV and 100% cranberry juice to her dog food (Iams proactive health).  ACV is a natural antibiotic and has numerous health benefits that I have used to treat myself as well as my pets in the past.  I added cranberry juice because it is suppose to be good for UTI's.  I have not been cleaning the area because there doesn't appear to be any discharge, and the area looks clean.  

So essentially, she appears to have a mild case of vaginitis caused by something, but i don't think its a UTI because she hasn't changed her eating or bathroom habits.  And she also seems to be improving slowly (decreased swelling) I hope.  

I feel I will have to take her to the vet soon, but am trying to avoid a large bill.  Since she appears to be fine otherwise I am going to give it some time and see if I can treat this on my own or if it will pass in due time.

Any advise you can give will be much appreciated.

Best Regards...

Answer
Many female dogs lick their groin area from allergies.  When they lick excessively, they can seed the vagina and urethra with bacteria and a UTI can occur.  So I would first have a urine sample checked to see if there really is a UTI.  If there is, antibiotic therapy usually knocks it out quickly.  Cranberry juice is ONLY for E. coli, so it may or may not help.

There are some dogs that are spayed and they have a small remnant of the ovarian tissue that remains.  They will exhibit signs of heat twice a year.  If there is no UTI and they treat for itching and everything goes away only to show swelling again in the fall, I would consider this as a possibility.