A case of MTHFR deficiency

IntroductionThis case highlights a rare, potentially treatable cause of adult-onset spastic paraparesis—methylenetetrahydrofolate reductase (MTHFR) deficiency. Early diagnosis of this metabolic disorder is essential to prevent disease progression and irreversible neurological damage. This report adds to the limited literature on late-onset MTHFR deficiency, emphasizing the importance of metabolic evaluation in unexplained spastic paraparesis.Patient Concerns and Clinical FindingsChief Complaints:Progressive stiffness in both lower limbs for 1 yearWeakness in both lower limbs for 5 monthsHistory of Present Illness:Difficulty wearing footwear and foot draggingPseudobulbar affectDifficulty walking, climbing stairs, and rising from a squatting positionGeneral Examination:Tall, well-built malePresence of gynecomastiaNeurological Examination:No cranial nerve deficits or sensory lossSpastic gait with Grade 3 spasticityExaggerated deep tendon reflexesBilateral extensor plantar responsesDiagnosis, Interventions, and OutcomeDiagnosis:Adult-onset MTHFR deficiency presenting as spastic paraparesis with hyperhomocysteinemiaInterventions:Anhydrous betaine (targeting homocysteine metabolism)Baclofen (for symptomatic spasticity relief)Outcome:The patient was discharged with improved lower limb strength (power +4/5 bilaterally) and is under regular follow-up for monitoring and ongoing management.Conclusion and Key Take awaysInborn errors of metabolism, including MTHFR deficiency, can manifest in adulthood.MTHFR deficiency, though rare, is a treatable cause of progressive neurological decline.Routine measurement of plasma homocysteine levels in cases of unexplained spastic paraparesis can facilitate early diagnosis and intervention, potentially preventing irreversible neurological damage.