Homocystinuria treated with pyridoxine.

Four cases of homocystinuria with lens luxation have been examined. As judged from the plasma amino acid pattern, they all responded well on pyridoxine treatment. Two of them discontinued the treatment on their own, and one of these died at the age of 17 years. The lens luxation progressed in one case despite adequate treatment. Scanning electron microscopy of one lens revealed partly broken zonules, abnormal zonular attachment, and a spongy appearance of the capsule proper. Hoping that adequate treatment will reduce more serious complications such as thromboembolism in these patients, it is concluded that an early diagnosis largely depends on the ophthalmologist, who should perform the silver-nitroprusside test, specific for homocystinuria, in all patients with non traumatic lens luxation.