Abnormal brain changes in a patient with vegetarian diet‑induced subacute combined degeneration: A case report

Subacute combined degeneration (SCD) is a neurological disorder caused by vitamin B12 deficiency, prevalent in the cervical and thoracic medullas, with an insidious onset and a lack of characteristic clinical manifestations. The present study describes a case of a 36-year-old female patient with SCD who demonstrated abnormal changes in the white matter of the brain. The laboratory test results showed a decrease in serum vitamin B12 levels and an increase in homocysteine levels. Magnetic resonance imaging (MRI) of the brain showed that, in addition to abnormal signals in the cervical and thoracic spine, speckled and short-striped abnormal signals were present, symmetrically distributed in the centrum semiovale. After 6 months of follow-up treatment, cranial MRI showed a significant attenuation of the symmetrical speckled and short-striped abnormal signals in the centrum semiovale. Homocysteine and serum vitamin B12 levels of the patient were within the expected range. Although, to the best of our knowledge, there have been no previous reports of alterations in the brain of patients with SCD, if these patients report neurological symptoms, clinicians should consider that these symptoms may be accompanied by inflammatory demyelination of the brain.