Thyroid or Pituitary Problem, or Normal?

[KimQ]

Two different GPs and my endo have tested me for thyroid issues this year because of my complaints of intermittant bouts with muscle spasms and cognitive issues.  All of the doctors say I have no thyroid related problems, but some internet friends disagree.  I am currently treated for secondary adrenal insufficiency by the endo.  I am receiving no thyroid treatment.  Is either a primary or secondary thyroid problem suggested by these numbers?  Thanks.

August 2010:  T3 Uptake%: 33.5 (23.0 - 37.0) Free T4: 0.89 (0.61 - 1.12) TSH: 0.340 (0.340 - 5.600)
July 2010: TSH 0.290 (0.340-5.600)
May 24, 2010: Free T3 2.58 (2.24-4.08) Free T4 1.10 (0.64-1.64) No TSH given.
May 9, 2010: TSH 0.322 (0.290-5.500)
January 2010: TSH 0.570 (0.340-5.600)

[Mark Lupo, M.D.]

Yes - if this was isolated low ACTH in the beginning, then vigilance for other pituitary dysfunction is required.

[Mark Lupo, M.D.]

Your T3 and T4 levels are consistently normal.  The TSH levels are in the low-normal range for the most part.  No definite thyroid issue at this time, but would continue monitoring.  Is the secondary adrenal insufficiency due to prior history of using steroid medications for another condition or is there a pituitary disorder?

[KimQ]

Dr. Lupo, one more question, if I may.  What significance, if any, do you see in my TSH numbers being consistently low or low normal?  Thank you.

[KimQ]

Isolated ACTH deficiency of unknown cause.  I've been on Hydrocortisone for about 10 years.  Is it at all likely that my pituitary might start to fail in other ways after all of this time?  Thanks for your reply.