Succinic semialdehyde dehydrogenase deficiency – a rare cause of metabolic stroke

Abstract

Succinic semialdehyde dehydrogenase (SSADH) deficiency is a rare neurometabolic disorder characterized by defective degradation of gamma-aminobutyric acid (GABA), a major inhibitory neurotransmitter of the brain. Children with SSADH deficiency present with motor mental delay, intractable seizures, infantile onset hypotonia, speech disturbances, extrapyramidal symptoms and ataxia. This wide spectrum results from increased accumulation of 4hydroxy butyric acid (4HBA) leading to down regulation of GABA receptors, which likely explain epileptogenesis but the pathophysiology of stroke in SSADH deficiency is not much elucidated. Here, we report an infant aged 11 months, product of consanguineous marriage with significant family history of motor delay and intellectual disability, presented with sudden onset focal neurological deficit preceded by diarrheal illness. Examination revealed an infant with age-appropriate milestones having left uncrossed hemiplegia along with neuroradiological evidence of right globus pallidus ischemic infarct. Urinary organic acid profile by chromatography was suggestive of 4 hydroxybutyric aciduria.