4 yo with Hyperthyroid

[lottsofcritters]

My 4 yo daughter was diagnosed with Hyperthyroid last week.  I had to request the test due to concerns about her energy level and insomnia.  She is VERY energetic!  Her attention is great, but she has trouble staying still.  She goes to bed at night with no problems at 8:30pm, however she rarely falls asleep before 11pm, then wakes up with no problems in the morning.  She also itches incessantly (she will go through four different outfits in the morning trying to find something that does not itch).  She is tall and skinny, 42.5 inches, and 52 lbs.  She eats ALOT!  she will have 4 packets of oatmeal and a glass of milk in the am.  Another possible symptom is nocturnal enuresis.  She is on DDAVP at night .05 mg X approx. 4 months.  If I remember to wake her up around 2am she may be dry, before the DDAVP she was going through 2 goodnights diapers a night...  if I didn't change it midway she and the bed would be completely soaked.

Anyway, her Thyroid was hyperactive, and she is allergic to Milk and Eggs (she did have hives when we were at the Dr).  The lab tests ordered were: Basic Metabolic w/EGFR, CBC w/ Diff/PLT, Immunocap, T-4Free, TSH w/reflex to FT4.  
The abnormal lab results are:  
T-4 Free: 3.0 (normal = 0.9 - 1.6),
TSH w/reflex to FT4: 0.01 (normal = 0.50 - 4.30),
Creatinine: 0.34 (normal = 0.50 - 1.20),
BUN/Creatinine Ratio: 32 (normal 6-22),
Platelet Count: 458 (normal = 140-400),
Milk IgE: 0.51 & Egg White (F1) IgE: 0.37     (normal <0.35)

The other piece of her history that may or may not be relevant is that when she was 9 mos old they discovered that her thymus was enlarged.  She was followed by a pediatric Hematologist-Oncologist for 4 months due to abnormal lab values, primarily elevated T-cells (CD4 & CD8) and the fact that they were finding 'immature' T-cells in her bloodstream.  

They did a thyroid US and a nodule was found measuring 0.4cm.  The US was done on friday, as well as a Thyroid panel.  

[Deanna L Aftab Guy, MD]

ok, you have clear labs that describe that she is indeed having hyperthyroidism, did they do thyroid antibodies or what is called a thyroid stimulating immunoglobulin level. Also with a nodule on ultrasound a I-123 radioactive iodine uptake study may be in order to rule out a hyperactive nodule versus graves disease versus Hashimoto's. You should be in the hands of a pediatric endocrinologist for her care, let them decide about the ddavp, this may be masking or exacerbating some of her symptoms.
You did not mention treatment yet and I am assuming until the etiology is made clear that treatment is on hold

[lottsofcritters]

Thank you so much for the information.  They did a 'full thyroid' test which was drawn on Friday.  I believe that is the thyroid antibodies test, also the US was done on Friday, I know about the nodule prior to report because I asked 'What is that?' and the tech said it looks like a nodule and she told me the measurements.  I am not exactly sure when the results will be in, but the US tech said our MD should have them Monday and when we did the last set of labs they were drawn on Friday and in on Monday... and that was when they didn't think her thyroid would be hyperactive.  I am hoping we will hear something tomorrow.  They did tell me that they would see how the imaging and labs came back this time and refer for pediatric endocrinology as indicated.  Initially he was not sure if they would want an US or an I-123 radioactive iodine uptake study due to her history of enlarged Thymus.  He consulted with the Radiologist and ordered the US.  Have you had any experience with Duke or UNC pediatric Endocrinology? Thank you for your help.  I can now have a reasonable idea of what to expect without reading too much into it.
Sheri!

[lottsofcritters]

Hello again.  I just thought I would update on my daughter.  We were referred to a Pediatric Endocrinologist at Duke.  They repeated the US and did a I-123 uptake scan as well.  Her thyroid measured 4.3 x 1.4 x 1.3 on the right side and 4.3 x 1.3 x 1.8 on the left side with the Isthmus measuring .4 cm.  She has a .6 cm nodule on the upper left lobe.  Her I-123 uptake was 37% at 4 hours and diffuse.  The ped endo noticed trembling in her fingers and tongue, as well as elevated BP and pulse.  We started her on PTU TID for 2 weeks and changed it this week to MTZ due to not needing the liquid formulation.  She seems to be tolerating the medicine okay but she has been very tired.  Sleeping much later than usual and going to sleep easier than normal.  Her levels were repeated this week T4 is still elevated, and TSH is slightly higher (actually measurable now).  The last set of labs showed the T4 higher than the original set and TSH lower than original.  T3 was also elevated.  Honestly all of the treatment options frighten me.  The side effects associated with the medications are only slightly better than not treating, and I would opt for surgery but apparently it is very difficult to find a surgeon able to operate on a 4 yo.  For now, we are trying the medication and will follow the nodule with US monitoring.  My main questions for now are: Is the sleepiness normal? and Are there any good surgeons for such young patients?
Thank you,
Sheri!

[lottsofcritters]

Also... the pediatrician ordered the antibody study before even sending us to the endo, but somehow it was not relayed to anyone that the test was not performed due to 'not enough blood for sample'.  The endo ordered it earlier this week when we repeated the labs.  I realized when I reread my post that the order of labs gets confusing.  First set Ped, second set Ped (even worse than first & no antibody study), third set Endo (T4 same, TSH up slightly, and antibody study pending).
Thanks!
Sheri!