High TSH and high FT4 , 2 year's old baby

[estrelinha]

Dear Dr. Lupo

Could you answer this post (RJ1221 asked me to try to post her question):
By RJ1221

Feb 05, 2009 11:47AM
My daughter who is Congenital Hypothyroid is now 2 and half year old has following readings:
FT4  - 26.48pmol/L   ( Range - 11.5 - 22.7)
TSH - 7.60  mclu/ml  ( Range - 0.7 - 6.4)

The last times reading was also with higher TSH - 14.51mclu/ml and FT4 - 20.40 pmol/L. The dosage was increased slightly and after 6 weeks I got the above stated readings. Most of the times I keep noticing this pattern , as on increasing the dosage the FT4 increases and though the TSH reduces better than previous time, but still higher on the normal range.
What can be the reason , I gathered about "if it is then consider thyroid hormone resistance or a TSH pituitary tumor -- both VERY VERY RARE." from this site.

Please find the below history of her reports if that can help further.

1 Year 5  25-Dec-07 1.53 0.8 - 2.3 ng/dL 4.77     0.7 - 5.7  ulU/mL
1 Year 7 19-Feb-08 1.6 0.8 - 2.3 ng/dL     12.85        0.7 - 5.7  ulU/mL

1 Y 10 M 13-May-08 24.49    11.5 - 22.7 pmol/L 2.98       0.7 - 6.4 mclU/ml
1 Y 11 M 26-Jun-08 28.57    11.5 - 22.7 pmol/L 2.53       0.7 - 6.4 mclU/ml
2 Y 1 M  20-Aug-08 25.19    11.5 - 22.7 pmol/L 4.49       0.7 - 6.4 mclU/ml
2 Y 5 M  16-Dec-08 20.4     11.5 - 22.7 pmol/L 14.51      0.7 - 6.4 mclU/ml
2 Y 6 M    4-Feb-09 26.48    11.5 - 22.7 pmol/L 7.6       0.7 - 6.4 mclU/ml

I am unable to post my query onto that expert forum as it always says that the limit of submissions are done for the day.

[Mark Lupo, M.D.]

This does not look like a pituitary tumor or thyroid hormone resistance as with these the T4 levels (and T3) are above the reference range when the TSH is above the reference range.  There are some levels that point that direction, but the overall pattern is more consistent with primary thyroid failure (ie, due to congenital hypothyroidism in this case) with fluctuating levels perhaps due to inconsistent absorption.  I wish I had a simple solution to this, but it will be important to have an over-view endocrine evaluation with a pediatric endocrinologist, then work closely w/ that person to stabilize the numbers.

[estrelinha]

Dr. Lupo
This are the baby's first lab values:
AGE         DATE FT4 (NORMAL RANGE) TSH     (NORMAL RANGE)
11 Days 29-Jul-06 0.29 0.9 - 2.6 ng/dL >500     1.7 - 9.1 ulU/mL
2 Months 11-Sep-06 3.1 0.9 - 2.6 ng/dL 0.13     1.7 - 9.1 ulU/mL
4 Months 12-Dec-06 1 0.9 - 2.6 ng/dL 145     0.8 - 8.2 ulU/mL
6 Months 27-Jan-07 2.5 0.9 - 2.6 ng/dL 0.03     0.8 - 8.2 ulU/mL
7 Months 15-Mar-07 0.9 0.9 - 2.6 ng/dL 8.4     0.8 - 8.2 ulU/mL
10 Months 1-May-07 1.44 0.9 - 2.6 ng/dL 0.3     0.8 - 8.2 ulU/mL
1 Year 2-Aug-07 1.4 0.8 - 2.3 ng/dL 10.3     0.7 - 5.7  ulU/mL
1 Year 3   1-Oct-07 1.9 0.8 - 2.3 ng/dL 2.8     0.7 - 5.7  ulU/mL
1 Year 4  13-Nov-07                 4     0.7 - 5.7  ulU/mL
1 Year 5  25-Dec-07 1.53 0.8 - 2.3 ng/dL 4.77     0.7 - 5.7  ulU/mL
1 Year 7 19-Feb-08 1.6 0.8 - 2.3 ng/dL     12.85        0.7 - 5.7  ulU/mL

Thankyou very much