Ectopia lentis in a child is seen in which of the following diseases?: (A) Sarcoidosis, (B) Homocystinuria, (C) Alkaptonuria, (D) Urea cycle defects
Answer is B. b. Homocystinuria(Ref: Nelson 20/e p 326)Ectopia lentis is one of the features of Homocystinuria, where the direction of lens subluxation is infero-medial, unlike supero-lateral subluxation in Marfan syndrome.