Diabetes after Radioiodine treatment?

[Audrey A]

Hello there
I’m new on here and just trying to find out some information regarding radioiodine treatment and the likelihood of developing diabetes afterwards. My 16 year old kitty, Pishee, was hyperthyroid, went through about a year and a half of Methimazole treatment and eventually got the radioiodine treatment about a month ago. She’s been drinking and urinating excessively for the last 3 weeks. We took her for the 1 month post iodine follow up with her vet and her labs show that her hyperthyroidism is under control, no kidney or heart issues, however she now how an elevated blood glucose over 500. Is this a coincidence or can this happen after radioiodine treatment? Is it transient or is this permanent? Anyone have any experience? My vet asked me to contact Dr. Micheal Broome (the vet that did the radioiodine treatment) to see how he thinks we should proceed, but his office said he’ll get back to me after 7 days!!! So in the meantime I wait? Anyone have any expo with something like this? Please???

 

[MrWorfMen's Mom]

There is definitely a connection between thyroid conditions and diabetes and the two often occur together. Now that your cat has been treated for the hyperthyroidism, it's quite possible the diabetes could go in remission. HERE is a brief video with some info from a cat endrocrine specialist.
Whether the radioiodine treatment itself would bring on the diabetes, I have no idea but my best guess would be that this is either simply a coincidence or your kitty isn't yet on the ideal dose of thyroid hormone and there is still some endocrine imbalance. If your cat just underwent the radioiodine Rx a month ago, it would seem quite plausible that the optimal dose of thyroid hormone has not yet been determined.

 

[Audrey A]

There is definitely a connection between thyroid conditions and diabetes and the two often occur together. Now that your cat has been treated for the hyperthyroidism, it's quite possible the diabetes could go in remission. HERE is a brief video with some info from a cat endrocrine specialist.
Whether the radioiodine treatment itself would bring on the diabetes, I have no idea but my best guess would be that this is either simply a coincidence or your kitty isn't yet on the ideal dose of thyroid hormone and there is still some endocrine imbalance. If your cat just underwent the radioiodine Rx a month ago, it would seem quite plausible that the optimal dose of thyroid hormone has not yet been determined.

Thank you I appreciate the info. Pishee’s considered euthyroid at this point meaning normal thyroid levels. She is, currently, not on any thyroid medication at all. I was wondering moreso whether the hyperthyroidism masked the diabetes much like they say it masks renal disease and heart failure, because she never had any abnormal blood glucose levels until after this treatment.
Again, I appreciate your time and the information you provided.
Thanks so much!

 

[MrWorfMen's Mom]

I'm familiar with this issue in humans more so than in cats. If glucose was never checked, yes the symptoms of hyperthyroidism could have masked the symptoms of diabetes. This is catch 22 situation because once the vet diagnosed Hyperthyroidism, they wouldn't likely continue to investigate for other conditions. Both hyperthyroidism and diabetes can present with the same symptoms of ravenous appetite, polyuria, polydipsia, and weight loss.
There may be other members who have dealt with this but I can't think of anyone specifically right now. I've seen cats on methimazole with diabetes go into remission with good regulation of their thyroid hormone levels.
Please keep us posted and let us know what the specialist has to say. And if you need any help with the diabetes, we're here to help in any way we can.