Mylo 7.5 Year Old Boxer - One Year In

[hmcpherson]

Mylo is our 7 1/2 year old boxer, who was diagnosed with pituitary Cushing a year ago and has been on 40mg vetoryl 2x day for the last 12 months. He’s had regular ACTH stim tests every three months the majority of his original symptoms had cleared up. He had a small patch of calcinosis cutis on his back that hadn’t fully healed yet but 8% better than at diagnosis. At diagnosis he weighed 38.8 KG and he currently weight 34.4 kg.

Fast forward to now and he seems to have to go out incessantly again and is drinking out a lot again. Our regular vet did another ACTH STIM and at the same time tested for a UTI. While the test grew a small amount of bacteria and he was treated with antibiotics with no improvement in drinking or urination.

We’ve been tracking his movements, water intake, food intake, timing of vetoryl doses, timing of everything. There is a trend that four hours after he receives his Vetoryl dose for a solid hour he’ll have to go out to pee nonstop (15 to 20 times in an hour). But then before that time and after that time, he seems to be fine. We recently went back to the internal medicine specialist and she increased his vetoryl dose to 45 mg two times a day. This is he’s been on this dose for one week and we haven’t seen any improvements yet.


His stim tests are below and we book the pre-blood draw 3 hours after his vetoryl dose on test day.

Mylo Stim Pre Post nmol/L

Feb 14, 2023 - pre 51, post 136

May 9, 2023 - pre 78, post 124

August 2, 2023 - pre 60, post 127

November 23, 2023 - pre <28, post 134 (His pre was low on test day so we retested just the pre on another day to see if it was a testing issue 1.5 hours after his morning dose and it was 151)

I am curious if anyone has experienced this constant need to urinate only in the 4-hour window after dosing. Is it possible in that four-hour window his cortisol is going too low? Or is our dose still too low?

Does anyone ever split the daily dose into 3x a day?

Thank you in advance for this forum and all of the help!

[Harley PoMMom]

Hi and welcome to you and Mylo!

I have manually approved your membership so now all your posts will be seen right away. Also, please just disregard the validation email that was sent to you from k9cushings.

Gosh I'm sorry for the reasons that brought you here but so glad you found us and we will help in any way we can. I've been a member on this forum for over 10 years and I don't believe I've ever had a member post about that trend of having to constantly urinate 4 hours after Vetoryl dosing. The IMS can contact Dechra, the makers of Vetoryl and see if they have any input, here is their info: "Please contact Dechra's 24-hour Veterinary Technical Support Team at support@dechra.com or 866-933-2472. One of Dechra’s best resources is our highly trained Veterinary Technical Support Team." This info was taken directly from their website here: https://www.dechra-us.com/contact/inquiry-form

I do remember a member who tried dosing 3 times a day but I'm not sure if that will help in your situation. I'm sorry I couldn't be of more help, hopefully Marianne, one of our Administrators, will be along with her insight.

Hugs, Lori

[labblab]

Hello and welcome from me, too! I’m so glad that Lori has already had the chance to greet you, and I definitely “second” her suggestion to ask your vet to contact Dechra. In all my years here, I’ve not heard of Milo’s specific behavioral response, either. It seems as though his excessive urination is peaking around the time that his Vetoryl dose is likely dropping his cortisol to its lowest level. So in a sense that seems really paradoxical for a Cushpup. If he was experiencing a general rebound in thirst/urination throughout the day or especially right before his next dose was due, I’d be more likely to guess that he does indeed need an increase in dose or frequency. And yes, I think on rare occasion dogs are dosed three times a day if the owner can handle that rigorous a routine.

But with Milo’s pattern, I’m really stumped. Really the only idea I can throw out there is that perhaps his pituitary tumor — or the Vetoryl itself — is affecting the production/release of a pituitary hormone labeled as ADH. This hormone helps control the release of water from the body, and a condition named “Diabetes Insipidus” can arise when there are related abnormalities with that hormone. (DI is totally different from the more common “Diabetes Mellitus” that causes elevated blood glucose levels.)


However, it is possible for diabetes insipidus to occur secondary to Cushing's disease. The elevated levels of steroids can interfere with the release of ADH from the pituitary gland. Also, excess steroids in the blood can interfere with how ADH binds at the receptors in the kidneys.

We’ve had dogs here who have been diagnosed with DI, but typically this condition results in excessive thirst/urination throughout the day, not just for a limited period of time. But still, since Mylo has been diagnosed with Cushing’s that is pituitary in origin, I wonder whether an abnormal release of ADH may be involved in some way. But a thorough understanding of DI is way above my pay grade, and it may be crazy to think it could have anything at all to do with Mylo’s limited periods of excessive urination. Regardless, I think consulting with the folks at Dechra could be very helpful because they may be aware of other abnormalities or imbalances that could also result in Mylo’s specific rebound pattern.

I’m sorry I can’t be more helpful, but I’m really glad you’ve found us, too. And we’ll definitely be anxious to find out how things progress for sweet Mylo.

Marianne

[hmcpherson]

Thank you both very much for your input. Originally when we were trying to diagnose Mylo the vet thought he had Diabetes Insipidus so we supplemented him with Desmopressin and it significantly improved his constant thirst and urination but then he developed Calcinosis Cutis on his back so the IMS confirmed Cushings with further tests as his cushings had progressed enough to be definitive. Mylo has been a tricky case and is the very best patient. I hope we can sort it out. I am going to mention to our IMS to call Dechra as well as think about DI again. We are open to doing whatever is needed as far as dosing. We ended up dosing his Desmopressin 3 times a day as well as it suited him best. We will keep you posted!

[labblab]

That is so interesting that Mylo responded positively to the Desmopressin previously, and it is indeed possible for dogs to suffer jointly from both DI and Cushing’s. Again, it seems odd that the symptoms are only rebounding at a specific and limited time of the day. But maybe it would be worth it to try resuming the Desmopressin again just as an experiment? We’ll surely be interested to hear what develops.

Marianne

[Squirt's Mom]

Hi and welcome to you and Milo!

My Bud has DI. At first we thought he had Cushing's but testing didn't support that diagnosis. He became lethargic, withdrawn, listless....just not his usual playful loving self. Sure enough his USG was 1.001 - ie almost pure water. He was drinking and peeing every 30 minutes max 24/7. He started on 1/2 tablet (0.2mg) od Desmopressin per day and currently is on 2 3/4 pills divided into three doses - 1am, 3/4 mid day, and 1 pm. And based on his behavior and urine color he will probably be getting an increase soon.

DI is quite rare. Bud is only the 2nd case our vet has seen in 40+ years of practice. I have a refractor at home and can check his urine myself and with vet approval decide his increases. Bud is doing very well thankfully. He does still have some of the signs of Cushing's but they are not consistent. At times he sheds like mad; at times his appetite is GINORMOUS; at times he pants out of the blue. But they aren't indicative of Cushing's in my mind nor the vet's so we are keeping on keeping as we are. Bud is much happier now that he's on the Desmopressin....and so am I! ;):D

But like others, that specific timing of the excessive pee and water intake is odd and I have not heard of this in my years working with cush pups either. That would be a very unique presentation of Cushing's OR DI...or any other condition I am aware of that impacts the urinary system. I would certainly ask the IMS to contact Dechra AND his peers to see if they have seen this with their cush patients. And, please, do let us know what you learn! You will be the one teaching us something! YAY!

Hugs,
Leslie