One possible trigger for Hashimoto's is infections....Yersinia is the most common trigger but there is much written in Lyme books about
Lyme causing thyroid issues.
Dr. Burrascano mentions this in his 2008 "Diagnostic Hints and Treatment Guidelines" in the pituitary section of page 6 here:
www.ilads.org/lyme/B_guidelines_12_17_08.pdf"Pituitary and other endocrine abnormalities are far more common than generally realized. Evaluate fully,
including growth hormone levels. Quite often, a full battery of provocative tests is in order to fully define the
problem. When testing the thyroid, measure free T3 and free T4 levels and TSH, and nuclear scanning and
testing for autoantibodies may be necessary.
Activation of the inflammatory cascade has been implicated in blockade of cellular hormone receptors. One
example of this is insulin resistance; clinical hypothyroidism can result from receptor blockade and thus
hypothyroidism can exist despite normal serum hormone levels. These may partly account for the dyslipidemia and weight gain that is noted in 80% of chronic Lyme patients."
The reason many people don't test positive on more bands is due to Lyme's suppression of the immune system - the effects of which are worsened in the presence of coinfections (especially Bartonella).
The Western Blot measures antibody response. Well, a suppressed immune system isn't going to mount a significant antibody response.
If Lyme is to blame for your Hashi's, proper treatment of the infection could very well result in an improvement in your thyroid function.
Mainstream doctors just haven't had the training to recognize Lyme even though it's so prevalent. That's why we need LLMD's.