Someone on another post raised the question of dogs and cats being hypothyroid. I became curious and found this article in the Merck Manual on treating animals with hypothyroidism:
Tests that may confirm the diagnosis include measurement of the serum concentrations of total T4, free T4, and TSH; provocative thyroid function tests (eg, TSH stimulation test); thyroid gland imaging; and response to thyroid hormone supplementation. Choice and interpretation of diagnostic tests is based heavily on the index of suspicion for hypothyroidism.
and this:
Total T4 concentration is the most commonly performed static thyroid hormone measurement and is a good initial screening test for hypothyroidism, with a diagnostic sensitivity of ~90%.
and this:
Unfortunately, serum TSH concentrations remain within the reference range in 20%–40% of dogs with confirmed hypothyroidism.
Interesting. Vets don't rely solely on the TSH test as doctors treating humans are advised to do.
Also: In practice guidelines for diagnosing humans with hypothyroidism I see little emphasis on cholesterol levels . Not so for animals:
The classic hematologic finding associated with hypothyroidism, found in 40%–50% of cases, is a normocytic, normochromic, nonregenerative anemia. The classic serum biochemical abnormality is hypercholesterolemia, which occurs in ~80% of dogs with hypothyroidism. The value of serum cholesterol determination as a screening test for hypothyroidism cannot be overemphasized, because cholesterol concentrations are a sensitive and inexpensive biochemical marker for this disease in dogs. Other clinicopathologic abnormalities may include high serum concentrations of triglycerides, alkaline phosphatase, and CK.
Perhaps endocrinologist (and GPs, too) should be required to study the diagnosis and treatment of animals with hypothyroidism.
Unfortunately, in this particular document, I see no mention of also providing endogenous T3 to hypothyroid animals who do not improve on T4 therapy.
Written by
vocalEK
To view profiles and participate in discussions please or .
I once went off on a little internet detour searching for 'hypothyroid horse'....... I ended up wondering if the way to better thyroid treatment was to pretend to be a horse!
My beautiful Greek dog was Hypo - and well looked after by our vet in Crete. It seems certain dogs are more prone - those beautiful elderly labradors with extra weight and poorly hips ?
In an absolute emergency maybe but no competent vet would ever diagnose or give medication to a human as there are huge differences between treating a dog and a human and there would be legal consequences if something went wrong. This info is from my daughter who is a Vet !
Sadly that’s so true. I joined this group in 2012/13 and we’ve been saying exactly that since back then - we’d get better treatment if we were an animal. All those years later and were still saying it.
One of my relatives cats has hyperthyroid and the vet wants to remove it's thyroid and charge them £500. I have told them not to have it's thyroid removed and try the medication for a while instead because it might go into remission. Not all vets are that helpful and charge you a lot of money for treatments.
Veternarians seem to understand physiology better than the average human doctor. Also there are no vet rheumatologists and seem to question the old autoimmunity theories ( about our immune system attacking itself for reasons not making sense). They understand better that it is the immune system's response after detecting stealthy pathogens causing collateral damage. They often deside to fight the microbes ( not always easy- there are very few weapons to do so as most antibiotics don't seem to work) instead of choosing immunosuppression as in humans ( vitamin d included) !
In searching for autoimmune and Vitamin D on PubMed, I came across this article:
Mounting evidence for vitamin D as an environmental factor affecting autoimmune disease prevalence
Margherita T Cantorna 1, Brett D Mahon
Affiliations expand
PMID: 15564440 DOI: 10.1177/153537020422901108
Abstract
Low vitamin D status has been implicated in the etiology of autoimmune diseases such as multiple sclerosis, rheumatoid arthritis, insulin-dependent diabetes mellitus, and inflammatory bowel disease. The optimal level of vitamin D intake required to support optimal immune function is not known but is likely to be at least that required for healthy bones. Experimentally, vitamin D deficiency results in the increased incidence of autoimmune disease. Mechanistically, the data point to a role for vitamin D in the development of self-tolerance. The vitamin D hormone (1,25-dihydroxy vitamin D(3)) regulates T helper cell (Th1) and dendritic cell function while inducing regulatory T-cell function. The net result is a decrease in the Th1-driven autoimmune response and decreased severity of symptoms. This review discusses the accumulating evidence pointing to a link between vitamin D and autoimmunity. Increased vitamin D intakes might decrease the incidence and severity of autoimmune diseases and the rate of bone fracture.
Corellation doesn't mean causation. Vitamin D is not a vitamin. It is a secosteroid and acts as such. The two metabolites calcidiol 25(OH)D and calcitriol 1,25(OH)D need to be both measured. A low 25D is often accompanied by an elevated (more than 40pg/ml) 1,25D as the result not the cause of chronic and autoimmune disease. The inactive hormone converts to the active one in an attempt to enhance the innate immune response, initiate the production of antimicrobial peptides and eliminate pathogens. Pathogens know that they don't stand a chance to survive and have developed strategies to block and disable the vitamin D receptor. Supplementing with vitamin D doesn't help in any way when these receptors are blocked. It has palliative effects - that's why almost everybody loves it. Less symptoms don't mean less disease! In the long run only harm can do. Believe me I was too naive and send me to hospital 3 times within 2 months! Please read this: fearlessparent.org/suppleme... and in more detals here: ncbi.nlm.nih.gov/pmc/articl...
And here's another set of veterinary thyroid guidelines that know more than your GP does about timing of FT4 test and dose.
Honestly i'm staring to think we should send the NICE guidelines off to 'vet's weekly magazine' for them to take the piss out of........ maybe 'the way to better thyroid treatment' is to embarrass all the endocrinologist's by having vet's laugh at them ?
INTERPRETING THYROID HORMONE CONCENTRATIONS WHEN THE PATIENT IS RECEIVING THYROID SUPPLEMENTATION
The canine therapeutic monitoring profile should be used. T4 and free T4 concentrations indicate that treatment has recently been received, and whether dosages are adequate to maintain levels within the normal range. For the most part, it gives us information about the dose, administration or absorption of the therapeutic product since the last pill was given, and is interpreted with regard to the hours post-pill at which the sample was drawn. TSH measurement gives a slightly longer-term picture of the adequacy of therapy (last two to four days). Concentrations of T3 indicate the adequacy of the active thyroid hormone metabolite.
On a BID protocol we hope to achieve values at the top or slightly above the reference range at the expected time of peak concentration (approximately three hours post pill) and a value within the lower half of the reference range if sampled just prior to the administration of the next pill (trough concentration). The target range, necessarily, depends on the interval post-pill at which the sample was obtained. The variability in T4 half-lives in dogs is sufficiently narrow that in a BID case a thyroid monitoring result can be interpreted with confidence anytime after three hours post-pill as long as that interval is known. Another aim of adequate thyroid supplementation is to keep TSH suppressed within the lower half of the reference range. A high TSH indicates demand for T4, and inadequate supplementation.
Yes, I have seen dogs in particular receive better care, right here in rural America, than the people in the same household. Vets take hypothyroid dogs off of grains, but humans in the same household treated by medical Drs. are given not even a hint that it may be beneficial. Further, when these same people pay hundreds of dollars for special foods, tests, etc. for their animals...when it is suggested that they do further inquiry for their own health, it’s - “The Dr. knows best..”. Meanwhile they spend days in bed suffering due to, many times, no treatment at all. The dogs, on the other hand are running all over hill and dale!
I have most recently subscribed to a newsletter (Dogs Naturally) and noticed some amazing similarities in the natural health remedies recommended for humans. It’s almost as if in offering health remedies for dogs, one circumnavigates the US disclaimer, “presented for informational purposes only, and not intended to diagnose or treat.”! Hey, I for one am taking notes. Dogs rule!
Vets usually care about their patients. Interesting. Having always owned many animals I would be pleased to be one now if that were possible. I might well feel better then.
Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.
Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.
New Research Shows TSH Test an Unreliable Test of Thyroid Function - Press Release
