OBJECTIVE: To describe the clinical, genetic, and biochemical characteristics of short-chain acyl-CoA dehydrogenase deficiency (SCADD), a clinically heterogeneous metabolic disorder for which neonates are screened for in parts of the United States and Australia. To explore the genotype-phenotype relation and to discuss neonatal screening for SCADD. DESIGN: Retrospective study of 31 Dutch SCADD patients and 8 SCADD relatives. METHOD: Patients and relatives were included ifbiochemical SCADD characteristics (increased C4-carnitine and/or ethylmalonic acid) were present in combination with a mutation and/or the c.511C>T or c.625G>A variant on each SCAD-encoding (ACADS) allele. The patients were subdivided into 3 genotype groups: mutation/mutation, mutation/variant and variant/variant group. RESULTS: A birth prevalence for SCADD of at least 1:50,000 was calculated. Most patients presented before the age of 3 years, mainly with developmental delay, epilepsy, behavioural disturbances and/or hypoglycaemia. The ACADS genotype showed a statistically significant association with biochemical, but not with clinical characteristics. In total 7 out of 8 SCADD relatives were free of symptoms. In 5 of the 31 patients, of whom 2 had severe symptoms, a second diagnosis was made which might explain the symptoms. CONCLUSION: SCADD was far more common than had previously been assumed and clinical symptoms in SCADD were non-specific, often transient or absent and not correlated with specific ACADS genotypes. SCADD does not meet major neonatal screening criteria and is therefore not suited for inclusion in neonatal screening programmes.
OBJECTIVE: To describe the clinical, genetic, and biochemical characteristics of short-chain acyl-CoA dehydrogenase deficiency (SCADD), a clinically heterogeneous metabolic disorder for which neonates are screened for in parts of the United States and Australia. To explore the genotype-phenotype relation and to discuss neonatal screening for SCADD. DESIGN: Retrospective study of 31 Dutch SCADD patients and 8 SCADD relatives. METHOD:Patients and relatives were included ifbiochemical SCADD characteristics (increased C4-carnitine and/or ethylmalonic acid) were present in combination with a mutation and/or the c.511C>T or c.625G>A variant on each SCAD-encoding (ACADS) allele. The patients were subdivided into 3 genotype groups: mutation/mutation, mutation/variant and variant/variant group. RESULTS: A birth prevalence for SCADD of at least 1:50,000 was calculated. Most patients presented before the age of 3 years, mainly with developmental delay, epilepsy, behavioural disturbances and/or hypoglycaemia. The ACADS genotype showed a statistically significant association with biochemical, but not with clinical characteristics. In total 7 out of 8 SCADD relatives were free of symptoms. In 5 of the 31 patients, of whom 2 had severe symptoms, a second diagnosis was made which might explain the symptoms. CONCLUSION: SCADD was far more common than had previously been assumed and clinical symptoms in SCADD were non-specific, often transient or absent and not correlated with specific ACADS genotypes. SCADD does not meet major neonatal screening criteria and is therefore not suited for inclusion in neonatal screening programmes.
Authors: Zarazuela Zolkipli; Christina B Pedersen; Anne-Marie Lamhonwah; Niels Gregersen; Ingrid Tein Journal: PLoS One Date: 2011-04-01 Impact factor: 3.240