[Anterior lenticonus: diagnostic aid in Alport syndrome].

Anterior lenticonus is a rare condition in which the lens presents a conical protrusion of its anterior cortex. Sometimes isolated, it may be an ocular manifestation of Alport syndrome, a hereditary nephritis accompanied by deafness and other ocular signs such as flecked retinopathy or posterior polymorphous corneal dystrophy. All these manifestations are a result of a genetic defect in type IV collagen, a major component of basal membranes in the human body. The clinical aspects and therapy of anterior lenticonus and Alport syndrome are described, as well as the exploration that must begin when anterior lenticonus is discovered. This exploration is essential so that this diagnosis can be made as soon as possible.