Neonatal screening avoids complications of delayed treatment

Editor–Johan R M Cruysberg and colleagues highlight the delay in diagnosis in patients with homocystinuria, describing a mean interval of 11 years from the onset of major signs until diagnosis.1 Early detection reduces the development of ocular complications.2 This is not achieved by good biochemical control alone, lens dislocation still developing in children when treatment is started outside the neonatal period.3

Neonatal screening affords the opportunity to improve outcome in homocystinuria, avoiding the complications that occur with delayed treatment. Untreated patients are particularly at risk of developing thrombotic disease, a clinically significant problem during surgery if the disease is undiagnosed. In his editorial David M Isherwood correctly states that hypermethioninaemia is unreliable for screening by Guthrie bacterial …