Graves disease

From greek.doctor

Graves disease, sometimes called Basedow disease, is the most common cause of hyperthyroidism in Western countries. It's an autoimmune condition. It’s caused by the immune system forming autoantibodies against the ligand-binding site on the TSH receptor on the follicular cells, which activates the receptor, stimulating thyroid function and growth.

It most commonly affects younger adult women.

Pathology

Goiter results from the hyperplasia stimulated by the TSH receptor, but the anti-TSH antibodies also stimulate fibroblasts. They stimulate fibroblasts in the orbit, which produce fibrofatty tissue which causes the eyeballs to be pushed outwards (exophthalmos). This condition is called Graves or endocrine ophthalmopathy. The antibodies also stimulate fibroblasts in the skin, causing them to produce more glycosaminoglycans, causing thyroid dermopathy, previously called pretibial myxoedema. The name pretibial myxoedema is misleading and old, as it doesn’t always occur on the tibia and doesn’t really cause just oedema. True myxedema occurs only in hypothyroidism.

Clinical features

In addition to hyperthyroidism, Graves disease causes a triad of symptoms:

Treatment

The treatment options for Graves disease are thyreostatic drugs, radioiodine ablation, and surgery. There are advantages and disadvantages for all types, and so the appropriate treatment is based on the severity, the presence of ophthalmopathy, the characteristics of the goitre, as well as the age of the patient. Radioiodine treatment worsens Graves ophthalmopathy, for which it’s a contraindication.

The major thyreostatic drugs are thiamazole and propylthiouracil, although lithium carbonate is also an option for short-term treatment. These drugs may have life-threatening side effects, especially agranulocytosis and liver failure, and so must be followed up regularly.

All three treatment modalities may be curative. However, thyreostatic drugs treatment is curative in only 50% of cases.

The following are treatment options for endocrine ophthalmopathy:

  • Smoking cessation
  • Corticosteroid treatment
  • Retrobulbar irradiation
  • Orbital decompression surgery or other ophthalmological surgery