Unintentional weight loss. Doctors don't know what's wrong

[phyllish]

Hey, my name is Phyllis and I am 20 years old.
Over the past few months, I have unintentionally lost a significant amount of weight (from 141, now 114). Because of this, I feel very weak and light-headed when I stand up. I have been eating more than enough of my caloric intake and although I used to live a very healthy, active lifestyle I have stopped exercising altogether.
The doctors have run many blood tests, and I have tested negative for HIV, diabetes, and any thyroid conditions. My RDW was a little on the low side (11.1 on a 11.6-14.8 reference range) Any other suggestions for what might be going on? As I currently don't have insurance I've only been able to go to my university's health center, so of course the testing has been limited.

[Barb135]

If TSH was the only test done for actual thyroid function and your doctor says you don't have a thyroid issue, you need to fire him, asap and find a different one.

Before thyroid can be ruled out, you need a Free T3 and Free T4 test... those are the actual thyroid hormones and are what determine whether or not you might be hyper.  

You also need the antibody tests to confirm/rule out, both, Graves Disease and Hashimoto's.  The tests you need are Thyroid Stimulating Immunoglobulin (TSI) to rule out Graves Disease and Thyroid Peroxidase Antibodies (TPOab) and Thyroglobulin Antibodies (TGab) to rule out Hashimoto's.

If your doctor refuses these tests, we can give you a web site, from which you can order them, for a reasonable price.

[phyllish]

The tests I got done are as follows:
IH-12 CBC

Test name - result | reference range -
WBC - 5.6 | 4.6-10.2
LYM - 1.6 | 0.6-4.1
MID - 0.6| 0.1-1.8
GRAN - 3.3 | 2.0-7.8
LYM % - 29.4 | 10.0-50.0 %
MID % - 10.9 | 0.1-24.0 %
GRA % - 59.7 | 37.0-80.0 %
RBC - 4.80 | 3.83-5.55
HGB - 14.1| 11.5-17.3
HCT - 43.4 | 35.0-51.0
MCV - 90.5 | 80.0-97.0
MCH - 29.4 | 26.0-32.0
MCHC - 32.5 | 31.0-36.0
RDW - 11.1 | 11.6-14.8 LOW
PLT - 254 | 140-440
MPV - 7.6 | 0.0-40.0

-
Ferritin - 69 | 29-322

-
Comprehensive Metabolic
Sodium - 141 | 135-146
Potassium - 4.1 | 3.4-5.0
Chloride - 103 | 96-108
Carbon Dioxide - Total - 27 | 22-29
Calcium - 9.8 | 8.5-10.4
Glucose - 83 | 70-99
BUN - 13 | 8-26
Creatine - 0.76 | 0.60-1.10
Estimated GFR (w/ MDRD equation) - >60
Total protein - 6.8 | 6.4-8.3
Albumin - 4.6 | 3.4-4.8
Bilirubin, Total - 0.3 | 0.1-1.3
ALKP - 56 | 0-205
AST - 15 | 0-36
ALT - 14 | 0-40

-
TSH - 2.02 | 0.40-5.50

restested TSH 1 month later- 1.43
-

HIV 1,2 ANTIBODY - Negative
-

IH-8 Sedimentation Rate - 2 | 0-20

-

Glucose, Fingerstick - 91 | 70-99
(Did not fast)

[Barb135]

What tests were done to rule out thyroid function issues?  Please post whatever test results you have, so we can better assess the situation.  

Were you tested for autoimmune thyroid disease, such as Graves Disease or Hashimoto's?  

Graves Disease is an autoimmune disease in which the thyroid produces too much thyroid hormone, which would seem to be your case.  Hashimoto's Thyroiditis is, typically, associated with hypothyroidism (under active thyroid); however, it can be characterized by periods of hyper in the beginning, alternating with either hypo or normal periods.

Symptoms of both of these diseases can appear before labs indicate an issue; that's why it's important to have the antibody tests.

Please post what blood tests you have, with results, and we can go from there.