cat diagnosed with atypical Addison's disease

[Jonas0]

Hello friends, my cat has been diagnosed with atypical Addison's disease following an ACTH test. His potassium and sodium levels are within normal range (based on latest blood test, as well as multiple blood tests taken over the course of the past two years prior to the Addison's diagnosis). However, the vet has prescribed Fludrocortisone, and I've noticed that my cat has grown somewhat more lethargic (and a lot more thirsty) since starting the medication last week. Now that I've read up about the disease, I am concerned my vet may have made a mistake (by his own admission he's not treated atypical Addison's before), and that my cat should in fact be receiving prednisolone instead (with no need for fludrocortisone!). Grateful for any advice from those with knowledge, expertise or experience with a similar case. Thank you!

 

[fionasmom]

This is not a hugely common condition in cats. I have had two dogs, one still living, with Cushing's disease which is the opposite of Addison's. In the old day before better canine meds were available for Cushing's, the course of treatment was to medically send the dog into Addison's and the treat him with prednisolone. That happened to my first dog; for this dog I have prednisolone on hand as a rescue med if he crashes from the Cushing's meds. The reason I mention this is that I have not ever had fludrocortisone given to me for a dog.

However, it is definitely used for cats and dogs. Dosing can be tricky, which is what you might be seeing with your cat. Given that you are noticing lethargy and thirst, I wonder if he is experiencing some side effects from it. Many vets are not well versed in Cushing's and Addison's because they don't see enough of it and many people do not bother to try to treat it. Can your cat be retested (fasten your seatbelt as a lot of retesting is necessary at times with both of these conditions) to see if his potassium and sodium levels are okay? With no disrespect to your vet, can you find one who is more versed in those conditions or do you have that option near you?

The reason your vet is probably using fludorcortisone is that it regulates both hormones at play in Addison's so as such it is not a careless choice in that respect and he might think that he is saving you some trouble with only one med. I have found that with these conditions the animal has to be monitored very carefully and anecdotally by the owner and you have to be prepared to contact the vet if something does not seem right.

 

[Jonas0]

Thank you very much for your detailed and informative response. I actually had to take my cat back to the vet on Friday after his condition seemed to deteriorate further. You were spot on with your suggestion about re-testing his sodium and potassium levels. Both were within normal range, and the vet agreed that fludrocortisone was probably not the best option moving forward. The vet administered a 10mg methylprednisolone injection, but mentioned that he would consider transitioning to prednisolone oral tablets once the cat's condition stabilises. I had omitted to mention in my original posting that my cat also has ringworm, and several courses of itraconazole had failed to resolve it. The vet explained his reasoning for not immediately opting for prednisolone, out of concern that it would further weaken my cat's ability to fight the ringworm.

It took over two years of misdiagnoses and outright veterinary malpractice by four other vets before my cat was recently diagnosed with Addison's. All it took was for his current vet to do the ACTH test. If I were to show you then and now photos of my cat, you wouldn't believe it's the same cat. I'm certain the road to recovery will be a difficult and long one.

 

[fionasmom]

For some reason, vets can be resistant to wanting to help Cushingoid animals, which of course includes Addisonian ones as well. I have known of many who gave it the "what are you going to do about it in the long run" approach and just ignored it. My dog was removed from the vet who dxed his Cushings because I knew after my experience with the first dog that she did not have much of an idea of what to do. The vet we see now is brilliant and the dog has lived with the condition for 6 years which is unheard of. ACTH stim tests themselves have about a 15% false negative rate and I believe to this day that I did have another Cushing's dog who simply continued to test negative despite symptoms.

Current vet does not sound bad and he did have a reason,which is actually quite solid, for not giving you pred. He also sounds as if he is willing to be flexible with his thinking which you have to be with these adrenal diseases.

I do hope that your road will not be long and difficult, but as I mentioned, it does require continual observation and monitoring.