AB101. Neonatal form of Isovaleric acidemia in Vietnamese patients: clinical history and outcomes

Background and objective: Isovaleric academia (IVA) is an autosomal recessive inborn error of leucine metabolism caused by a deficiency of the mitochondrial enzyme isovaleryl-CoA dehydrogenase (IVD). The clinical presentation of IVA appears to be highly variable ranging from severely affected to asymptomatic subjects. This is the first report of Vietnamese patients with IVA. Describe clinical features and outcome of Vietnamese patients with IVA.

Methods: Case series report including three Vietnamese patients who were diagnosed IVA with the criteria of elevation of C5 and urinary isovalerylglycines, 3-OH-isovalerate using Tandem Mass and GC/MS.

Results: Three probands (2 female and 1 male) from three unrelated families were born to non-consanguinity parents. The age of onset was within the first 2 weeks of age (8, 9 and 10 days). The male patient had older brother died due to unknown comma at 18 days old. The initial symptom was poor feeding (3/3). After 1-2 days of the onset, they appeared lethargy/comma (3/3), convulsion (1/3) and respiratory failure required mechanical ventilation in one case. The investigations revealed metabolic acidosis (PH: 7.2-7.3) in 3 cases, thrombopenia in 3 cases; ketonuria in 3 cases and hyperammonemia in 3 cases. Management for acute crisis and long-term follow up of IVA was started after 2-3 days of the onset: coma was released after 2-3 days of treatment. All patients have normal development at 16 months of age; at 15 months of age and at 10 months of age, respectively.

Conclusions: Three Vietnamese patients with IVA presented early initial symptoms within 2 weeks of age and have good outcome.

Keywords: Isovaleric academia (IVA)