Thyroiditis (Thyroid Gland Inflammation): Causes

Pathogenesis (disease development) of acute thyroiditis

Acute suppurative thyroiditis is caused by infection with bacteria, viruses, fungi, etc. Most often, the cause is a piriform sinus, a developmental remnant. In older individuals, a long-standing goiter or thyroid tumor may be causative.

Etiology (causes) of acute thyroiditis

Disease-related causes

Infectious and parasitic diseases (A00-B99).

Pathogenesis (disease development) of thyroiditis de Quervain (subacute thyroiditis)

The etiology of thyroiditis de Quervain is still unclear. It is thought to be associated with a viral infection. Furthermore, there is probably a genetic predisposition.

Histological examination reveals infiltration with granulocytes (infection defense cells) and monocytes (cells of the immune system that are precursors of macrophages (phagocytes)) (granulomatous, pseudotuberculous, noninfectious giant cell thyroiditis). This leads to destruction of the normal structure of the thyroid gland.

Etiology (causes) of thyroiditis de Quervain (subacute thyroiditis)

Biographic causes

  • Genetic burden from parents, grandparents – detection of HLA-B37 (could be detected in >60% of affected individuals).

Disease-related causes

Respiratory system (J00-J99)

  • Respiratory infection, unspecified

Pathogenesis and etiology of Hashimoto’s thyroiditis [see below Hashimoto’s thyroiditis].

Etiology (causes) of other forms of thyroiditis

Disease-related causes.

Endocrine, nutritional, and metabolic diseases (E00-E90).

  • Autoimmune thyroiditis (AIT; thyroiditis caused by autoimmune processes):
  • Silent thyroiditis (silent thyroiditis) – thyroiditis belonging to the autoimmune thyroiditis with a mild course.
  • Postpartum thyroiditis (PPT; postpartum thyroiditis) – first occurrence of autoimmune thyroiditis (AIT) up to 12 months after delivery with antibody detection in existing euthyroidism (normal thyroid function); in approx. Four percent of pregnant women; high-risk patients are women who have been found to have elevated thyroid antibodies (TPO antibodies) before or during pregnancy and women with diabetes mellitus, Graves’ disease or chronic viral hepatitis.

Infectious and parasitic diseases (A00-B99).

  • Acute thyroiditis infection of the thyroid gland triggered by bacteria, viruses, fungi, etc.; mainly staphylococci, streptococci; Aspergillus, Candida.
  • Parasitic thyroiditis – caused by parasites such as Echinococcus (tapeworms) or Strongylidae (palisade worms).

Neoplasms – tumor diseases (C00-D48).

  • Carcinoma-associated thyroiditis – thyroiditis occurring in the setting of a malignant neoplasm.

Other causes

  • Radiation thyroiditis – after irradiation with radioactive iodine; self-limiting.

Medication

  • Drug-induced thyroiditis (synonym: drug-induced thyroiditis) – especially after the ingestion of
    • Amiodarone
    • Immune checkpoint inhibitors such as programmed-cell-death-protein-1(PD-1) or cytotoxic T-lymphocyte antigen-4 (CTLA-4) antibodies
    • Lithium
    • Cytokines (interferon alpha, interleukin-2)