Maladie de Coats et télangiectasies primaires ou secondaires

Coats' disease, or primary retinal telangiectasia, is a rare exudative retinopathy, usually unilateral, that most commonly affects male children in the first decade of life. It is probably a congenital disease, non hereditary, without any associated systemic disorders. The disease is characterized by primary telangiectasia and exudates resulting in possible retinal detachment, vitreo-retinal haemorrhages, neovascular glaucoma and ultimate loss of vision. The primary lesion is most likely a localized progressive disorder of the retinal vascularization development. Its exact aetiology remains unclear, but the disease may be caused by somatic mutation in the NDP (Norrie Disease Protein) gene. A subtype of primary retinal telangiectasia, the idiopathic juxtafoveal telangiectasia confined to the macula, constitutes a second clinical form. Secondary telangiectasia and retinal exudates may occur in relation with local or systemic disorders such as retinal vein occlusion, actinic retinopathy or diabetes.