Hashimoto's Thyroiditis

Question 1

What is it?

Answer 1

a gradual failure in thyroid function due to auto-immune destruction of thyroid tissue
there is reduced thyroid hormone production

Question 2

who gets it?

Answer 2

10-20F:1M
45-60 years old
Often a family history of autoimmune thyroiditis or other autoimmune disorders
Antibodies against thyroid peroxidase (TPO)
T-cell infiltrate and inflammation microscopically
o CD8 +ve cells may mediate destruction of thyroid epithelium
o Cytokine mediated cell death – γ interferon from T cell activation recruits macrophages that may damage thyroid follicles

Question 3

how does it present?

Answer 3

diffusely enlarged thyroid
prominent lymphoid infiltrate - lymphocytes, plasma cells and reactive follicles with germinal centres
thyroid follicles atrophy - follicular cells have abundant eosinophilic cytoplasm (hurthle cells)
may see progressive fibrosis within the gland
may be preceded by a transient hyperfunction (Hashitoxicosis)
at increased risk of other AI diseases
increased risk of developing B cell NHL in affected gland