A Rare Treatable Complication of Neuroregression in Glutaric Aciduria Type 1 Management: Vitamin B12 Deficiency

Abstract Introduction  Glutaric aciduria type 1 is a rare treatable inborn error of metabolism caused due to deficiency of the enzyme glutaryl-CoA dehydrogenase. A restrictive lysine and tryptophan diet has significantly improved the outcome of presymptomatically diagnosed glutaric aciduria type 1 children. Case  Here we present the case of a 6-month-old male infant with glutaric aciduria type 1 diagnosed based on clinical, biochemical, radiological, and genetically confirmed case on therapy with homemade diet modification. The patient later developed regression of milestones at 16 months of age while on treatment with good compliance. On examination, pallor and hypopigmented sparse hair with knuckle hyperpigmentation were noted. Investigation revealed low vitamin B12 levels. On vitamin B12 supplementation, the child showed significant improvement. Conclusion  A reversible cause needs to be looked for in patients on dietary restriction and formula feeds treated for metabolic disorders.