Introduction 

Riedel’s thyroiditis is a chronic inflammatory disease associated with fibrosis or woody enlargement of all or part of the thyroid gland 

-it is now considered a IgG4-related systemic disease 

-Women in midlife are most often affected 

Symptoms & Signs 

-Symptoms of hypothyroidism when enough thyroid tissue is replaced by fibrous tissue; compressive symptoms of the esophagus, trachea such as dysphagia, dyspnea, hoarseness; a hard, ‘woody’ thyroid gland

Diagnosis 

Gross exam: hard, fixed, ‘woody’ thyroid gland 

Labs: normal or low thyroid hormones, normal or elevated TSH, normal or elevated IgG4 levels 

Open thyroid biopsy: a dense lymphoplasmacytic infiltrate rich in IgG4 plasma cells, storiform fibrosis, and obliterative phlebitis

Treatment 

Surgery: decompression through thyroidectomy Hypothyroidism: thyroid hormone replacement

subacute (de Quervain or Granulomatous) viral thyroiditis

Introduction 

Subacute thyroiditis is an acute painful disease of the thyroid probably caused by a virus or postinfectious inflammation 

-Measles, mumps, influenza, adenoviruses are among the commonly blamed viruses 

-It occurs between 30 and 50 years of age; it is three to five times more common in females than in males 

-It is often associated with HLA-B35

Symptoms & Signs 

Fever, anterior neck pain, aggravated by swallowing; pain frequently refers to the ear; a markedly tender thyroid gland upon palpation with one or more nodules; in the acute phase the patient may be euthyroid or hyperthyroid

Diagnosis 

Labs: Early hyperthyroidism is followed by a hypothyroid phase and later euthyroid phase

Biopsy: Lymphocytes and multinucleated giant cells

Treatment 

Aspirin, NSAIDS, glucocorticoids, β-adrenergic blockers; monitor TSH, T4 every two weeks; Complete recovery in most cases