Ord's Disease

Named after William M. Ord (1834-1902)
Synonymes: Autoimmune thyroiditis type 1B, Autoimmune thyroiditis type Typ 2B, Atrophic Thyroiditis
German: Ord-Thyreoiditis

1 Definition

Ord's disease refers to an autoimmune disease of the thyroid (Autoimmune Thyroiditis). This entity has been first described by William M. Ord in 1877.

2 Etiology and Pathogenesis

The disease is characterized by a destruction of thyroid tissue that is caused by different cellular and humoral immune processes. While detailled trigger mechanisms are still unknown, it has become clear that formation of microsomal antibodies against thyroid peroxidase (TPO-AB) and of antibodies against thyroglobulin (Tg-AB) plays a critical role. These antibodies precipitate impaired thyroid function.

A small percentage of Ord patients seems to be antibody negative, but this subpopulation may be difficult to separate from patients with elapsed silent thyroiditis.

3 Classification

• Autoimmune thyroiditis type 1B: Euthyroidism
• Autoimmune thyroiditis type 2B: Hypothyroidism

4 Diagnosis

Diagnostical criteria for Ord's disease are:

• Decreased thyroid volume (normal: 15 to 18 mL in females, 20 to 25 mL in males)
• hypoechogenic pattern in ultrasonography
• Reduced Technetium-Uptake (TcTU) in thyroid scintigraphy
• Positive Tg-AB and/or TPO-AB.

5 Symptoms

Symptoms of Ord's disease are varying and ambiguous. Most cases show abortive course or proceed with very few symptoms being easily treated by substituting thyroid hormones.

6 Therapy

There is no evidence for an effective activity of immunosuppressive angents.

Therapy consists in normalizing plasma levels of thyroid hormones. Hypothyroidism is treated with life-long substituting levothyroxine. Selenium may help to reduce antibody levels.

7 Prognosis

Ord's disease doesn't heal up why it requires life-long substitution with T4. The disease may sometimes be associated with cervical lymphomas. Therefore regular investigation of neck and thyroid via ultrasonography is recommended.