Low-Level Laser Therapy in Chronic Autoimmune Thyroiditis
Low-Level Laser Therapy in Chronic Autoimmune Thyroiditis
The purpose of this study is to evaluate whether low-level Laser therapy is effective in
 ameliorating the thyroid function of patients with hypothyroidism caused by chronic
 autoimmune thyroiditis.
Chronic autoimmune thyroiditis (CAT) is the most common cause of hypothyroidism in
 iodine-replete areas. An autoimmune dysfunction causes humoral and cellular responses that
 lead progressively to thyroiditis. There is no effective therapy available that can change
 the natural history of CAT, which presents a high incidence of hypothyroidism and requires
 continuous treatment with levothyroxine (LT4).

 Laser light can be valuable since the local and systemic actions of low-level laser therapy
 (LLLT) have been shown to be effective in treating autoimmune diseases, such as rheumatoid
 arthritis and Sjogren's syndrome. There is also evidence suggesting that LLLT can facilitate
 regeneration of various tissues and, in animal thyroids, can lead to improvement in
 microcirculation and increases in serum triiodothyronine (T3) and thyroxine (T4) levels.
 Since the LLLT is a non-invasive, cost-effective and painless procedure, the objective of
 this randomized clinical trial was to evaluate the effectiveness of LLLT in patients with
 hypothyroidism caused by chronic autoimmune thyroiditis, based on patients' thyroid function,
 their concentration of thyroid autoantibodies, and the parameters of their ultrasonography
 study.
Inclusion Criteria:

 -  Patients previously diagnosed with hypothyroidism induced by chronic autoimmune
 thyroiditis (CAT). The presence of hypothyroidism, laboratory measurements and
 ultrasonography criteria were applied to diagnose CAT.

 -  Significantly elevated concentrations of thyroid peroxidase (TPOAb) and/or
 thyroglobulin (TgAb) autoantibodies

 -  Ultrasonography results consistent with CAT

 -  Patients undergoing LT4 treatment

 -  Normal (or almost normal) levels of triiodothyronine (T3), thyroxine (T4), free T4 and
 thyrotropin (TSH)

 Exclusion Criteria:

 -  Use of immunosuppressants, immunostimulants, or other drugs that could interfere with
 the production, metabolism and transport of thyroid hormones

 -  CAT with normal thyroid function

 -  CAT with subclinical hypothyroidism

 -  Thyroid nodules

 -  Hypothyroidism stemming from post-partum thyroiditis (up to 18 months after gestation)

 -  History of Graves' disease

 -  Thyrotropin receptor antibody (TRAb) detectable

 -  Prior treatment with radioiodine

 -  Tracheal stenosis

 -  Pregnancy

 -  History of ionizing irradiation and/or neoplasia in the cervical area

 -  Previous surgical intervention in the thyroid

 -  Thyroid hypoplasia

 -  Ectopic thyroid

 -  Serious illness (cancer, ischemic coronary artery disease, stroke, kidney or liver
 failure, etc.)