Hashimoto's Thyroiditis

Synonyms

Hashimoto's disease; Goitrous autoimmune thyroiditis [1]

Definition and Characteristics

Positive thyroid peroxidase antibodies (TPO Ab), elevated serum thyrotropin, lymphocytic infiltration of the thyroid gland and presence of a goiter on clinical examination [1].

Prevalence

The most common cause of acquired hypothyroidism [1,2], sevenfold more common in women [1] with increasing incidence after the age of 45 [3].

Genes

There is a genetic predisposition for Hashimoto's thyroiditis, as patients with human leukocyte antigen (HLA) class I and class II (HLA-DR3, HLA-DR4, HLA-DR5), polymorphisms in the region of the cytotoxic T lymphocyte antigen 4 (CTLA-4) gene on chromosome 2q33 or on chromosomes 6p, 13q32, 12q22 are more susceptible to the development of Hashimoto's thyroiditis [4].

Molecular and Systemic Pathophysiology

Hashimoto's thyroiditis is characterized by diffuse lymphocytic infiltration, gradual destruction of the gland and fibrosis.