VLCAD deficiency: Follow-up and outcome of patients diagnosed through newborn screening in Victoria

• Published in: Molecular genetics and metabolism Vol. 118; no. 4; pp. 282 - 287
• Main Authors: Evans, Maureen, Andresen, Brage S., Nation, Judy, Boneh, Avihu
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.2016
• Subjects: Acyl-CoA Dehydrogenase, Long-Chain - deficiency; Acyl-CoA Dehydrogenase, Long-Chain - genetics; Body composition; Body Composition - drug effects; Body Composition - genetics; Child; Child, Preschool; Fatty acid oxidation; Female; Follow-Up Studies; Humans; Infant, Newborn; Lipid Metabolism - drug effects; Lipid Metabolism - genetics; Lipid Metabolism, Inborn Errors - diet therapy; Lipid Metabolism, Inborn Errors - genetics; Lipid Metabolism, Inborn Errors - physiopathology; Male; Mitochondrial Diseases - diet therapy; Mitochondrial Diseases - genetics; Mitochondrial Diseases - physiopathology; Muscular Diseases - diet therapy; Muscular Diseases - genetics; Muscular Diseases - physiopathology; Mutation; Neonatal Screening; Triglycerides - administration & dosage; VLCAD deficiency; Fatty acid oxidation; VLCAD deficiency; Body composition
• ISSN: 1096-7192; 1096-7206
• DOI: 10.1016/j.ymgme.2016.05.012

Very long chain acyl-CoA dehydrogenase (VLCAD) deficiency is an inherited metabolic disorder of fatty acid oxidation. Treatment practices of the disorder have changed over the past 10–15years since this disorder was included in newborn screening programs and patients were diagnosed pre-symptomatically. A genotype-phenotype correlation has been suggested but the discovery of novel mutations make this knowledge limited. Herein, we describe our experience in treating patients (n=22) diagnosed through newborn screening and mutational confirmation and followed up over a median period of 104months. We report five novel mutations. In 2013 we formalised our treatment protocol, which essentially follows a European consensus paper from 2009 and our own experience. The prescribed low natural fat diet is relaxed for patients who are asymptomatic when reaching age 5years but medium-chain triglyceride oil is recommended before and after physical activity regardless of age. Metabolic stability, growth, development and cardiac function are satisfactory in all patients. There were no episodes of encephalopathy or hypoglycaemia but three patients had episodes of muscle pain with our without rhabdomyolysis. Body composition studies showed a negative association between dietary protein intake and percent body fat. Larger patient cohort and longer follow up time are required for further elucidation of genotype-phenotype correlations and for establishing the role of dietary protein in metabolic stability and long-term healthier body composition in patients with VLCAD deficiency. •Mutation analysis may potentially indicate the need for treatment: ‘if’ and ‘when’.•Prescribed low fat diet is relaxed for asymptomatic patients at 5years of age.•Medium-chain triglyceride oil is recommended around physical activity at all ages.•There is a negative association between protein intake and percent body fat.