Low T4, Normal TSH - Secondary Hypothyroidism?

[Celia75]

Hi,

I am a 33 year old female with a strong family history of secondary hypothyroidism. My mother, grandmother, maternal uncle, and twin sister have all been diagnosed specifically with the pituitary-related form of the disease. I have been experiencing several symptoms of hypothyroidism for the last 11 years and doctors have ordered thyroid function tests 3 times in the last decade. None of those tests have resulted in a diagnosis.

Every few years I seek out a doctor to investigate why I am cold intolerant, unable to sleep, unable to lose weight, fuzzy-brained, itchy, have zero libido, and am not menstruating normally. In each case I am told that, in addition to symptoms that I verbalize, I exhibit physical characteristics of someone with hypothyroidism and/or PCOS. Then then the blood work comes back "normal" and the diagnosis quickly changes to "mild depression" or "lack of sufficient exercise". This has been very frustrating for me, so this year I requested a copy of the results so I could see what my levels were. The blood work showed the following:

T4                   5.2   (5.3-11.5 mcg/dL)
T-UPTAKE       37   (32-48 %)
TSH               2.10  (0.34-5.60 mcIU/mL)

I realize the T4 is just below the normal cutoff, but do you think these results warrant me seeking out an endocrinologist for further testing? I asked my current doctor if she would refer me and she seemed a little hesitant. I am not usually pushy, especially with doctors, but I really just want to feel better.

I would appreciate any advice/opinions.

[goolarra]

Your FT4 is too low.  TSH is a pituitary hormone.  It is much less important than FT4.  Has your FT3 been tested?  This is the test that correlates best with symptoms.  T3 uptake is considered an obsolete test and has been replaced by FT3.  Currently accepted TSH range is 0.3-3.0, so yours is in the upper part of the range.  

Get your FT3 tested, but I definitely think you might feel better on meds to bring your FT4 up.  Many people don't feel well until FT4 is midrange or higher.

[compnet]

Boy does this sound familiar.

"So I am being treated for low T4, but my TSH shows up in the 'normal' levels."  Anyone think I could be treated the same or is this uncommon?

[Celia75]

Thanks for the reply. I'm glad you're getting things sorted out. My mother and sister are both on Synthroid and have responded really well. I just need a diagnosis first!

[anree]

I really don't know a ton about the numbers, so someone will have to help out in that area. I know that my TSH levels were considered normal, but my Free T4 was low. I was put on too much synthroid and I went Hyper. But now that I have started a lower dose of Armour I have been feeling a little better. So I am being treated for low T4, but my TSH shows up in the 'normal' levels. Maybe someone who knows a little more can shed light on it. I know my symptoms for 6 years, was tiredness, 4 years, depression, low sex drive, and then since 2 months ago I have had SEVERE hair loss. That finally tipped the Dr. off that it might be my thyroid!