Folate metabolism disorder presenting as an opticospinal syndrome

Area of Science:

• Neurology
• Genetics
• Immunology

Background:

• Opticospinal syndrome, affecting the optic nerve and spinal cord in young adults, is typically attributed to immune-mediated diseases.
• Conditions like multiple sclerosis and neuromyelitis optica spectrum disorder often present with relapsing-remitting courses and respond to corticosteroids.

Purpose of the Study:

• To report a case of opticospinal syndrome initially responsive to steroids, revealing an underlying genetic cause.
• To highlight that steroid responsiveness is not exclusively indicative of inflammatory demyelinating disorders.

Main Methods:

• Clinical case presentation of a young adult with opticospinal syndrome.
• Genetic analysis to identify pathogenic mutations.
• Assessment of response to treatments, including corticosteroids and folate supplementation.

Main Results:

• The patient presented with opticospinal syndrome and initial steroid responsiveness.
• A pathogenic mutation in the methylenetetrahydrofolate reductase (MTHFR) gene was identified, leading to folate deficiency.
• Neurological complications and skin hyperpigmentation were observed, suggesting a metabolic etiology.

Conclusions:

• Opticospinal syndrome can have metabolic origins, such as MTHFR gene mutations and folate deficiency, not solely immune-mediated causes.
• Relying solely on steroid responsiveness can lead to misdiagnosis; metabolic investigations are crucial.
• This case underscores the importance of considering genetic and metabolic etiologies in opticospinal syndrome presentations.