Current choices for treating feline hyperthyroidism include: daily medication, surgery, or radioiodine therapy. I opted for the third choice, radioidine therapy. Herman seemed to be a good candidate; he had a full geriatric blood panel and dentistry done just 3 months prior, and everything was normal on his bloodwork and he did fine post-dental. The recent bloodwork showed a mild elevation in the Blood Urea Nitrogen (BUN) but the creatinine was still in the normal range. These are two parameters that measure kidney function on a blood test. His blood count was abnormal though; the white count was high, and antibiotics were initiated. I was happy that the hyperthyroid disease was caught early, and he was in seemingly good health on a day-to-day basis.
I scheduled an appointment with a radioiodine treatment center a few hours away, and plans were made for travel. Two days before the trip, the veterinarian specialist called to say that she was concerned about Herman's kidney values on the most recent bloodwork. Even though the values looked "good for his age", she said that since he was confirmed hyperthyroid, those values should be even better, i.e. much lower. This is because hyperthyroidism causes an increase in the heart rate and the increased heart rate causes more blood to flow through the kidneys; creating a situation where the blood values for the kidneys look better than they may actually be. The kidneys are essentially supported by the increased flow, and if the thyroid hormones are removed suddenly (and permanently) as with the radioiodine treatment, the "hidden" kidney problems can quickly come to the forefront and be a serious problem much quicker than the often slow phase of kidney failure in cats.
New plan: start oral medications for two weeks to see how the kidneys perform with the drop in thyroid hormone. We did a cystocentesis (collect a urine sample via a needle into the bladder), and the concentration was low with a few bacteria and cells seen. A blood count was repeated, and it was improving back to near normal levels. I continued Herman on the course of antibiotics.
Herman has been maintaining a "senior level" of activity and his appetite is fair. On some days he sleeps most of the day, and on others, he wrestles with his 16-year old feline housemate, Greta, or chases little balls of paper around. He is the most lovable cat, and doesn't like to be made a fuss over, which is hard for me, worrying as I do. I am sure that kidney failure is the main thing to deal with at this point. Repeat lab tests are scheduled for later this week. Updated laboratory information -- next page.
Related Reading
Treatment Options For Hyperthyroidism In Cats
What is Apathetic Hyperthyroidism?
Feline Hyperthyroidism Resources
