Glutaric aciduria type I: outcome following detection by newborn screening

Glutaric aciduria type I (GA I), a cerebral organic acidaemia with the potential for severe neurological consequences, can now be detected by tandem mass spectrometry newborn screening. Early detection with implementation of careful management strategies appears to lessen the likelihood of neurological damage. We assessed the outcome in all 10 GA I patients detected in New South Wales during the last decade. Three patients were detected clinically and 7 by newborn screening. Diagnosis was confirmed by detection of significantly elevated urinary 3-hydroxybutyrate and glutarate in urine, isolated elevation of glutarylcarnitine in plasma, typical clinical and MRI findings in several, and mutation analysis or enzyme analysis on cultured skin fibroblasts in 4 cases. The birth frequency was 1:90,000. Following diagnosis, treatment was initiated in all children with oral carnitine (100 mg/kg per day) and a low-protein diet supplemented with a lysine-free, low-tryptophan amino acid formula. Disability was assessed in fields of motor, cognitive and speech development and scored according to Kyllerman. Clinically diagnosed patients were all symptomatic, with severity scores (out of 9) of 3, 5 and 9. Six of seven patients detected by newborn screening are asymptomatic, 4 being aged 2-6 years. One patient had a severe decompensation at 7 months, despite full management advice and treatment, and later died. Our data support previous findings that early diagnosis reduces neurological complications, but show that even with early diagnosis and careful management severe complications may ensue in some.

The burden of genetic disorders in India and a framework for community control

With a very large population and high birth rate, and consanguineous marriage favoured in many communities, there is a high prevalence of genetic disorders in India. An estimated 495,000 infants with congenital malformations, 390,000 with G6PD deficiency, 21,400 with Down syndrome, 9,000 with beta-thalassaemia, 5,200 with sickle cell disease, and 9,760 with amino acid disorders are born each year. The prevalence of late-onset multi-factorial disorders (including coronary artery disease, hypertension and psychiatric disorders) is also large. Due to inadequate diagnostic, management and rehabilitation facilities, the burden of these disorders is greater than in Western countries. Although genetic diseases receive little attention from the health services, research funding by the government has been liberal. Community control of common disorders like thalassaemia, Down syndrome, neural tube defects, and muscular dystrophies deserves high priority, and genetic services should be integrated into the existing primary health care and medical services. Most genetic counselling would have to be provided through training physicians who staff the district and medical school hospitals. To ensure future progress, there is a need to establish additional departments of medical genetics in medical schools.