Weird thyroid numbers, Please help. (one for the books)

[sgound00]

I was wondering if you have any ideas about my thyroid problem. I just saw an endocrinologist last week, and am just waiting now to do a couple of tests for him.

My most recent numbers for the Thyroid are:
TSH: 23  (normal .3-5.5)
Free T4: 34 (normal 10-20)
Free T3: 4.7 (normal 3.5-6.5)

As you can see, I have an elevated TSH indicating hypothyroidism, yet I have an extremely elevated fT4. I was looking online to see if there is other cases of this. I have read that sometimes the Pituitary might have a tumor which is causing it to release TSH eventhough my fT4 is high. However i feel extremely Hypo, gained 20 plbs in 8 weeks ever since my numbers got messed up. Im currently on Synthroid 112mcg.

[goolarra]

Well, your labs are a bit puzzling.  On 100 mcg, your FT4 was low, and on just 25 mcg more, it had skyrocketed out of range.  

I looked up drug interactions, and nothing came up for prednisone and levo.  Whether or not it could affect conversion, I don't know.  However, what's going on here is not strictly a conversion issue.  Your FT4 went up a LOT on a very little increase.  Of course, we're believing the doctor when he said it was low on 100 mcg...maybe you should get the actual results from him to verify that???  

Were you taking the prdnisone for a gut issue?  It almost looks like you weren't absorbing and then started to.

So, that's one issue, and conversion is the other.  With your very high FT4, conversion is going to start shunting a lot more converted T4 into RT3 rather than T3.  That's the body's natural protection against too high FT3 levels.  RT3 is inert.  I tend to think your FT4 is just so high, that your FT3 is lowering to compensate.  Your FT3 level might actually be higher with a more reasonable FT4 level.

Then there's your TSH.  Wow, you've got it all going!  LOL  If I have this right, you were on 100 mcg, feeling good, and your TSH was still 12, prompting your doctor to raise your meds to 125 mcg.  Is that correct?  Look into PRTH.  In a nutshell...the pituitary converts T4 to T3 for itself.  With PRTH, the enzyme responsible for converting T4 to T3 within the pituitary is missing or inadequate.  The pituitary is starved for T3, so it thinks the whole body is and cranks out TSH.  Meanwhile, peripheral conversion can be just fine (it's a separate issue).  

My symptoms were very similar to yours.  My symptoms went away, but my PCP wanted to keep increasing my meds to get my TSH down.  My TSH hovers around 20.0 permanently.  I don't believe PRTH would be picked up on a prolactin test.  

[sgound00]

One last thing, by the time I had taken the synthroid 100mcg test. All my symptoms were gone at that point. Lost the majority of my weight gain in about 5 weeks. So i was feeling a lot better on 100mcg, than I am on 112mcg. Could the prednisone effect the conversion of T3 to T4. all my doctors said no.

[sgound00]

Thanks so much for responding so fast.

I'm taking the synthroid because I was diagnosed with Hashimotos by an internist 7 months ago. I guess there are a lot more details that I failed to mention.

Prior to starting synthroid.
Having every hypo symptom in the book.
TSH: Is greater than 150. (lab didnt give an actual number)
Free T4:Dont remember (doc said it was low)

Synthroid 100mcg
TSH: 12
Free T4: Doc said it was low.

Synthroid 125mcg
TSH:2.5
Free T4:40

Synthroid 112mcg
TSH:23
Free T4: 34

Seems like things went haywire between the 125 and 112. I should also mention that I started taking prednisone 1 week prior to taking my test while on the 125mcg, which was about 1.5weeks prior to starting the 112mcg. I took the 125mcg test while on 20mg of pred, and the 112 most recently while on 5mg of pred.

My pituitary test just came in.
Prolactin: 11 (normal <15)

My Endo doesnt have all my previous tests (eg. Anti-TPO), so we're waiting for that one to come in right now. However I spoke to my hematologist yesterday because shes administering my prednisone, and she told me that the internist did do the Anti-TPO and therefore was certain I do have Hasimoto's

[goolarra]

I just thought I'd chime in with my personal experience to supplement gimel's excellent advice.

You don't necessarily have to have a pituitary tumor for your TSH to be high.  There are other pituitary issues that can cause it as well.  I have pituitary resistance to thyroid hormone (PRTH), and it's impossible for me to get my TSH below about 20.0 although my FT3 and FT4 are in range, and I'm asymptomatic.  

I have to re-iterate what gimel said...why are you on T4 meds with your FT4 well above range?  It would seem your doctor is reacting to your TSH level and not really paying any attention to FT3 and FT4.  I also agree that I'd ask for an RT3 test.  It's virtually certain that with your high FT4 and low FT3 , your RT3 has to be high to protect your body against too high levels of FT3.  Very high FT4 levels can make you feel more hypo by stimulating the conversion of T4 to RT3 rather than FT3.    

[gimel]

From your high Free T4 and high TSH, it appears that there is something strange happening, so evaluating your pituitary function is definitely in order.  Your hypo feelings appear to be due to low- in- the range Free T3, apparently due to inadequate conversion of T4 to T3.  This is apparent in the huge imbalance between FT4 and FT3 levels within their ranges.  You should also test for Reverse T3, to determine if excessive conversion of T4 to Reverse T3 is occurring.  

Just because your Free T3 is within the range does not mean that it is okay for you.  The ranges for both Free T3 and Free T4 are far too broad.  I won't get into the reasons why that is the case.  Suffice to say that many of our members, myself included, report that hypo symptom relief for them required that Free T3 was adjusted into the upper third of its range and Free T4 adjusted to around the middle of its range.  Scientific studies have shown that Free T3 correlated best with hypo symptoms, while Free t4 and TSH did not correlate at all.

When you go for additional testing, I suggest that you should also include Vitamin D, B12, and ferritin.

In view of your possible pituitary issue and your test results, why are you taking 112 mcg of T4 med?