Thyroid gland diseases and skinE00-E07

Hyper- and hypothyroidism belong to the most important thyroid diseases from a dermatological point of view.

• Besides diabetes mellitus, hyperthyroidism is the most common endocrine disease in adults with a gynaecotropy of 5:1 and is rare in children. Hyperthyroidism includes all diseases that are associated with a peripheral oversupply of thyroid hormones. The two most common are autoimmune hyperthyroidism(immunogenic hyperthyroidism of the M. Graves type) and functional autonomy (autonomous adenoma or multinodular goiter).
• Hypothyroidism can be congenital (1:5,000 newborns) or acquired. Acquired most frequently as a consequence of chronic lymphocytic thyroiditis(autoimmune thyroiditis Hashimoto), rarely also in the context of a polyglandular autoimmune syndrome or iatrogenic (e.g. after strumectomy).

Overview of the most common dermatologic symptoms and disorders in thyroid disease:

• Skin changes in hyperthyroidism:
  • Acropachy (irregular periosteal proliferation on the end phalanges of the fingers and toes I to III).
  • Alopecia areata
  • Alopecia, diffuse
  • Alopecia: along the frontal hairline with displacement of the frontal hairline cranially. Patchy, hairless patches.
  • EMO syndrome (exophthalmos pretibial myxedema osteoarthropathy syndrome).
  • Hyperhidrosis
  • Hyperpigmentation (localized periorbital or generalized - see below melasma)
  • Koilonychia
  • Mucinosis cutaneous infantile (questionable association)
  • Myxedema, pretibial
  • myxoedema, diffuse
  • Onycholysis.
• Skin changes in hypothyroidism:
  • Acropachy (hypertrophy of long bones, distal bone ends and skin of extremities with drumstick fingers).
  • Eruptive xanthomas
  • Hair: rough and shaggy, breaks off easily
  • Slow hair growth
  • Skin, dry, cold, rough
  • Capillary fragility
  • Macroglossia
  • Myxedema
  • Nails thin, streaky
  • Nail growth, delayed
  • Onycholysis (rare)
  • Pachydermoperiostosis, symptomatic
  • Rarefication of the lateral eyebrows
  • Drumstick finger.
• Skin changes in autoimmune thyroiditis (Hashimoto's):
  • Canities praecox (pernicious anemia; thyroiditis).
  • Dermatitis herpetiformis (Hashimoto's thyroiditis)
  • Cat scratch disease (complicative thyroiditis)
  • Lichen sclerosus et atrophicus
  • Myxoedema circumscriptum symmetricum praetibiale (Hashimoto's thyroiditis is rare)
  • Polychondritis recidivans et atrophicans (Hashimoto's thyroiditis)
  • Pruritus sine materia
  • Sjögren's syndrome (Hashimoto's thyroiditis; anti-SS-A and/or anti-SSB AK)
  • Scleroderma, systemic
  • Urticaria (immunological)
  • Vitiligo (Hashimoto's thyroiditis)
  • S.a. Polyendocrinologic syndrome, autoimmunologic.
• Skin lesions and thyroid tumors:
  • Acanthosis nigricans maligna in thyroid carcinoma.
  • Amyloidosis (medullary thyroid carcinoma)
  • Birt-Hogg-Dubé syndrome (thyroid carcinoma, hypothyroidism)
  • Cowden syndrome (thyroid carcinoma)
  • MMN syndrome
  • Sipple syndrome (multiple endocrine neoplasia, including thyroid carcinoma)
  • Wermer syndrome.

• Dermatological leading symptoms of hyperthyroidism are:
  • Hyperhidrosis with tender, velvety skin
  • heat intolerance
  • brittle nails
  • fine thin hair.
• In the full-blown Graves ' disease, diffuse, periorbital hyperpigmentation (haloed eyes) is pronounced in addition to exophthalmos. If the hyperpigmentation intensifies in the inner corner of the eye, it is called a "Jellinek's sign".
• In hypothyrosis, congenital and acquired hypothyroidism are distinguished. For dermatologic differential diagnosis, the symptoms of the acquired forms are particularly significant. Acquired forms of hypothyroidism are observed from the age of 2 years. The following dermatological symptoms are relevant:
  • increased sensitivity to cold
  • dry, somewhat thickened, rough (knees and elbows increased) pale skin (with yellowish undertone)
  • Myxedema with doughy, non-push-in swellings of the eyelids, face, hands and lower legs.

1. Ai J, Leonhardt JM et al (2003) Autoimmune thyroid diseases: etiology, pathogenesis, and dermatologic manifestations. J Am Acad Dermatol 48: 641-659
2. Heymann WR (1992) Cutaneous manifestations of thyroid disease. J Am Acad Dermatol 26: 885-902
3. Jabbour SA (2003) Cutaneous manifestations of endocrine disorders: a guide for dermatologists. At J Clin Dermatol 4: 315-331