Mccune-albright syndrome Q78.10

McCune and Bruch 1936; Albright, Butler and Hampton 1937; Lichtenstein 1938

Very rarely occurring syndrome with a triad of fibrous dysplasia, pubertas praecox, and uncharacteristically confugured café-au-lait spots that are bizarrely frayed at the margins.

Sporadic genetic mosaicism (postzygotic gene mutation in one or more somatic cells) of the"Guanine nucleotide binding protein (G protein), alpha stimulating activity polypeptide 1" gene (GNAS gene) gene locus: 20q13.2.

Integument: Mostly characteristic from birth, uniformly milk-coffee-colored, band-shaped or oval, sharply delimited, hyperpigmentation of skin and mucous membranes following the Blaschko lines. The spots are usually present only in small numbers, with the edges usually irregularly fissured ("coast-of-maine spots"- see Fig.), often also half-sided, sharply bordered to the midline (cutaneous mosaic). This distinguishes them from the multiple, rounded café-au-lait spots that occur in peripheral neurofibromatosis.

Extracutaneous manifestations: pubertas praecox with premature epiphyseal closure in female patients, consecutive short stature, acromegaly.

Monotopic or polytopic fibrous dysplasia with thinning of the cortical bone and fibrous replacement of the bone marrow. As a consequence: tendency to fractures, scoliosis and others.

Multiple endocrine disorders with autonomy of functional end organs, e.g. hyperthyroidism, Cushing's syndrome, hyperparathyroidism.

Statistically increased rate for breast cancer, thyroid cancer, and various forms of bone cancer.

• Avoidance of direct sunlight and consistent textile and physical/chemical sun protection. Light protection agents including the UVA range are recommended.
• If necessary, try depigmentation with bleaching agents such as hydroquinone (e.g. Pigmanorm) or with 20% azelaic acid (e.g. Skinoren).

  Remember! Depigmentation with hydroquinone is irreversible and only starts after several months!

• Alternatively cover with camouflage (e.g. Dermacolor, R025 ). Therapy trials with artificial tanning agents are also available (e.g. Vitadye), reapply every 2-3 days.

1. Albright F, Butler AM, Hampton AO (1937) Syndrome characterized by osteitis fibrosa disseminata, areas of pigmentation and endocrine dysfunction, with precocious puberty in females. N Engl J Med 216: 727-747
2. Angelousi A et al (2015) McCune Albright syndrome and bilateral adrenal hyperplasia: the GNAS mutation may only be present in adrenal tissue. Hormones (Athens) 14:447-450
3. Brillante B et al (2015) McCune-Albright syndrome: An overview of clinical features. J Pediatr Nurs 30:815-817.
4. Diercks K et al (1996) Primary cutaneous osteoma in hereditary Albright osteodystrophy. Dermatologist 47: 673-675
5. Jhala DN et al (2003) Osteosarcoma in a patient with McCune-Albright syndrome and Mazabraud's syndrome: a case report emphasizing the cytological and cytogenetic findings. Hum Pathol 34: 1354-1357
6. Leet AI et al (2004) Fracture incidence in polyostotic fibrous dysplasia and the McCune-Albright syndrome. J Bone Miner Res 19: 571-577.
7. Lichtenstein L (1938) Polyostotic fibrous dysplasia. Arch Surg 36: 874-898
8. Lichtenstein L, Jaffe HL (1942) Fibrous dysplasia of the bone: a condition affecting one, several or many bones, the graver cases of which may present abnormal pigmentation of skin, premature sexual development, hyperthyroidism or still other extraskeletal abnormalities. Arch Path 33: 777-816
9. McCune DJ, Bruch H (1936) Osteodystrophia fibrosa: report of a case in which the condition was combined with precocious puberty, pathologic pigmentation of the skin and hyperthyroidism, with a review of the literature. Am J Dis Child 54: 806-848

10. Spencer T et al (2019) The Clinical Spectrum of McCune-Albright Syndrome and Its Management. Horm Res Paediatr 92:347-356.

11. Wagner P et al (2002) Fibrous dysplasia: differential diagnosis from Paget's disease. Dtsch Med Wochenschr 127: 2264-2268.