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Vol 33, No 61 (2023)
Case report
Published online: 2024-02-22

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Vitamin B12 deficiency encephalopaty as a potentially reversible brain injury — case study based on several years of a patient’s observation

Anna Frączek-Szczepkowska1
DOI: 10.5603/cn.98936
Neurol Dziec 2023;33(61):1-7.


Vitamin B12 is one of the neurotropic vitamins that are key to the proper functioning of the nervous system. It participates in the metabolism of nucleic acids, the synthesis of DNA and biogenic amines, and is also necessary in the transformation of fats resulting, among other things, in an effective process of myelinisation. In severe cases, vitamin B12 deficiency, regardless of the cause, leads to the onset of symptoms from the nervous and hematopoietic systems, as well as to psychiatric symptoms. The most common neurological disorders in infants and small children include: retardation of psychomotor development, progressive weakness, muscle hypotonia, hyporeflexia, tremors, convulsions, ataxia, psychomotor regression. The following article presents the diagnostic and therapeutic process and long-term results of treatment of an 11-month-old boy with symptoms of encephalopathy caused by vitamin B12 deficiency. The diagnostics of encephalopathy in infants and small children should take into account deficiency-related, potentially reversible causes, due to the possibility of rapid and effective treatment to prevent persistent neurological problems.

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Child Neurology — Neurologia Dziecięca