Involuntary movements and magnetic resonance imaging findings in infantile cobalamine (vitamin B12) deficiency.

Abstract

Infantile vitamin B12 (vit B12) deficiency is encountered in malnourished infants or in offspring of strict vegan mothers or mothers with pernicious anemia and accompanied by hematologic and neurologic findings. We present here a 16-month-old infant whose mother had vit B12 deficiency with low socioeconomic level admitted to our hospital. On admission, the patient was apathic, hypotonic, and lethargic. Serum vit B12 level was below detectable limits. On cranial magnetic resonance imaging (MRI), T2-weighted images revealed bilateral frontal and parietal periventricular high-signal symmetric lesions in the white matter (delayed myelination) and frontoparietal cortical atrophy. On day 3 of vit B12 therapy, involuntary movements were observed. Vit B12 is an essential vitamin and needs to be supplied by diet. Although a vit B12-deficient diet can be tolerated by the adults for years from the endogenous pool, deficiency in infants may become symptomatic in a few months because of the limited hepatic reserve.1 Infantile vit B12 deficiency is common in malnourished offspring of vegan mothers and mothers with pernicious anemia and has a clinical course of ineffective hematopoiesis and neurodegenerative signs.1–5 Here, we present a 16-month-old male infant who had severe vit B12 deficiency accompanied by hematologic, neurologic, and typical MRI findings. A 16-month-old male infant was admitted to our hospital for fever and tendency to sleep. His past medical history revealed that his mental and motor development were normal up to 8 months of age. He subsequently became lethargic and showed developmental regression. He was hospitalized for irritability and … Reprint requests to (Z.A.) Department of Pediatrics, Fatih University School of Medicine, Alparslan Turkeþ cad. No: 57, 06510, Beþtepe, Ankara, Turkey. E-mail: zekaiavci{at}yahoo.com