Coats’ Disease

Coats’ disease

Coats’ disease is a rare, non‑neoplastic telangiectatic retinal vasculopathy characterised by peripheral retinal telangiectasia, aneurysmal dilatation and progressive intraretinal and subretinal lipid exudation.

Accumulation of subretinal fluid and lipids may cause an exudative (serous) retinal detachment and secondary complications (uveitis, cataract, neovascular glaucoma, phthisis bulbi). It most commonly presents in childhood with leukocoria or new strabismus and must be distinguished urgently from retinoblastoma.

Epidemiology and genetics

• Incidence approximately 0.09 per 100,000 (UK data).
• Usually unilateral (≈95%) and more common in males (male:female ≈ 3:1).
• Typical age at diagnosis is childhood and adolescence (most commonly 8-16 years); about two‑thirds present by age 10.
• No simple Mendelian inheritance; reported chromosomal instability (chromosomes 3 and 13) and associations with NDP, CRB1 and PANK2 have been described.

Pathophysiology

• The primary lesion is incompetent retinal capillaries (telangiectasia) that leak lipid‑rich serum into the retina and subretinal space.
• Chronic leakage produces massive exudation and may progress to exudative retinal detachment.
• Longstanding disease leads to inflammation, secondary glaucoma and ultimately phthisis if untreated.

Clinical features

• Common presentations: leukocoria (white/yellow pupillary reflex on flash photos), new‑onset strabismus, reduced or deteriorating vision, and abnormal visual behaviour (poor fixation, loss of depth perception).