Lens subluxation in homocystinuria. A case report

A 6-year-old girl had bilaterally subluxated lenses and liver and platelet dysfunctions. A cyanide-nitroprusside test of the urine was positive. Serum and urinary levels of methionine and homocystine were high. Cystathionine synthetase activity in the cultured skin fibroblasts was negligible. Pyridoxine, 1000 mg/day orally, normalized the serum and urinary methionine and homocystine levels and the liver and platelet functions. Episodes of pupillary block glaucoma prompted lens extraction. The subluxated lenses were extracted under general anaesthesia after administration of pyridoxine and dextran to avoid thrombosis. A good result without serious complications was obtained. We believe that homocystinuria should not be considered a contra-indication to general anaesthesia. In the pyridoxine-responsive patient general anaesthesia is not hazardous if platelet function can be controlled by the vitamin.