Classical hemocystinuria in two Filipino patients

Classical hemocystinuria is an inborn error of metabolism caused by a deficiency of cystathionine beta-synthase that converts hemocysteine to cystathionine. This then leads to elevation of hemocysteine which results in abnormalities of the eyes, skeleton, central nervous system and vascular hemocystinuria. Patient 1 presented with lens dislocation and mental retardation while Patient 2 presented with thromboembolism, mental retardation and lens dislocation. The elevated plasma hemocysteine and methionine levels lead to the diagnosis of hemocystinuria.