AS per your letter,your ALT and AST are mildly elevated.No need for further evaluation regarding this.
These enzymes are elevated not only in Hepatitis
,but also on many other diseases.so,There is no need to test for hepatitis now.
There is no relationship to the reduced dose of Thyroid medication.
in the neck have to examined and evaluated.It may be due to simple infection or Tuberculosis
or Cancers like lymphoma
Please consult your surgeon and proceed.
Wish you good health