Albinism

Albinism comprises a group of inherited disorders of melanin synthesis causing reduced pigmentation of skin, hair, and eyes, with characteristic visual impairment.

• Oculocutaneous albinism (OCA), autosomal recessive: OCA1 (TYR; OCA1A no melanin, OCA1B some pigment), OCA2 (OCA2/P gene, commonest in sub-Saharan Africa, about 1 in 3,900 in some countries), OCA3 (TYRP1), OCA4 (SLC45A2), and OCA5 to 8. Ocular albinism type 1 (GPR143) is X-linked.
• Syndromic forms: Hermansky-Pudlak syndrome (HPS; bleeding diathesis, pulmonary fibrosis, granulomatous colitis) and Chediak-Higashi syndrome (immunodeficiency, giant lysosomal granules, haemophagocytic lymphohistiocytosis).
• Skin cancer risk is very high in regions with intense UV exposure (SCC, BCC, melanoma), and early mortality from squamous cell carcinoma is common in sub-Saharan Africa.
• Stigma, discrimination, and in some regions violence and persecution affect people with albinism.

• Skin and hair colour from white to light brown depending on type; sun sensitivity with burning, no tanning, freckles and lentigines in OCA2.
• Eye findings: nystagmus, photophobia, reduced visual acuity (6/18 to 6/60), iris transillumination, foveal hypoplasia, strabismus, refractive errors (high astigmatism, hypermetropia), and optic nerve misrouting.
• Actinic damage: solar keratoses, actinic cheilitis, SCC (early age).
• HPS: easy bruising and bleeding; Chediak-Higashi: recurrent infection, neuropathy.

• Clinical diagnosis from phenotype and family history, with ophthalmological examination.
• Visual evoked potentials show optic nerve misrouting.
• Genetic testing for TYR, OCA2, TYRP1, SLC45A2, GPR143, and HPS genes; hair bulb tyrosinase assay (historical).
• If bleeding or immunodeficiency: platelet aggregation and platelet dense granule deficiency (HPS), blood film for giant granules (Chediak-Higashi), and pulmonary function tests and chest CT in HPS.
• Skin cancer screening with dermoscopy and biopsy of suspicious lesions.

• Strict photoprotection: broad spectrum SPF 50+ sunscreen applied liberally and reapplied every 2 hours, UV-protective clothing, wide brimmed hats, sunglasses with UV protection, and sun avoidance during peak hours; provide sunscreens in resource limited settings.
• Skin surveillance: full body examination every 6 months (or more often in Africa) from childhood; early treatment of actinic keratosis (cryotherapy, topical 5-fluorouracil 5%, imiquimod 5%) and prompt surgical excision of skin cancers.
• Vision care: early ophthalmology review, spectacle correction (tinted lenses), low vision aids, school accommodations (large print, seating near the board), strabismus surgery, and tinted contact lenses. Gene therapy trials ongoing (nitisinone investigational).
• HPS: avoid aspirin and NSAIDs, desmopressin for bleeding, antifibrotic therapy (pirfenidone) for pulmonary fibrosis. Chediak-Higashi: HSCT for accelerated phase.
• Psychosocial and community support: education, anti-stigma programmes, safety measures, and genetic counselling.