Typically, Hashimoto thyroiditis also called autoimmune thyroiditis is viewed as a single organ autoimmune disease. However, we should not forget that it is part of an autoimmune family diseases. Hashimoto thyroiditis is frequently found in association with other autoimmune conditions and well-differentiated connective tissue diseases.
Non-endocrine associations of hypothyroidism and Hashimoto thyroiditis have been described including rheumatic manifestations such as osteoarthritis and erosive osteoarthritis, inflammatory arthritis resembling rheumatoid arthritis, calcium pyrophosphate dihydrate deposition disease, myositis, spinal degenerative disc disease, carpal tunnel syndrome and Raynaud’s phenomenon.
Hashimoto thyroiditis has been linked independently with fibromyalgia and chronic widespread pain.
Rheumatoid arthritis and Hashimoto’s may come together as normally family members do. Research shows a 33 % incidence of fibromyalgia
in Hashimoto thyroiditis patients.
There is a positive association between the Hashimoto’s antibody (TPOAb), fibromyalgia syndrome and chronic widespread pain in patients with rheumatoid arthritis. The role of inflammation and inflammatory cytokines in generating chronic pain syndromes is very well known. It might be also that the elevations in TSH: thyroid-stimulating hormone which increase deposition of proteoglycan in musculoskeletal tissues through stimulation of adenylate cyclase causing pain and stiffness. Additionally, there might be an interplay between a number of peripheral and central nervous system mechanisms leading to generalized pain.
A retrospective cohort study shows that there may be an association of anti-thyroid peroxidase antibodies (TPOAb) with fibromyalgia and chronic widespread pain. The assessment of antithyroid autoantibodies in the early workup of rheumatoid arthritis patients might provide important prognostic and clinical information regarding their risk for chronic pain syndromes.
References:
Ahmad, J., Blumen, H., & Tagoe, C. E. (2015). Association of antithyroid peroxidase antibody with fibromyalgia in rheumatoid arthritis. Rheumatology International, 35(8), 1415-1421. doi:10.1007/s00296-015-3278-1
Ahmad, J., & Tagoe, C. E. (2014). Fibromyalgia and chronic widespread pain in autoimmune thyroid disease. Clinical Rheumatology, 33(7), 885-891. doi:10.1007/s10067-014-2490-9
Tagoe, C. E., Zezon, A., Khattri, S., & Castellanos, P. (2013). Rheumatic manifestations of euthyroid, anti-thyroid antibody-positive patients. Rheumatology International. doi:10.1007/s00296-012-2616-9
