Neuromyelitis optica spectrum disorder with painful tonic spasms as the first symptom: a case report.

BACKGROUND

Painful tonic spasms (PTS) are an underrecognized initial manifestation of neuromyelitis optica spectrum disorder (NMOSD), presenting before classic neurological deficits in rare cases.

CASE PRESENTATION: A 51-year-old man presented with progressive right lower limb PTS lasting ≤10 s, spreading bilaterally and impairing mobility within 1 month. Neurological examination showed bilateral hyperreflexia and myoclonus. Spinal MRI revealed longitudinally extensive T2 hyperintensity and gadolinium enhancement at T1-T6 levels. Serum aquaporin-4 immunoglobulin G (AQP4-IgG) antibody was positive (1:100), while cerebrospinal fluid AQP4-IgG analysis was negative. Methylprednisolone (0.5 g/day for 3 days, tapered to oral prednisolone) and intravenous immunoglobulin (0.4 g/kg/day for 5 days) significantly reduced spasms. At discharge, he ambulated independently without PTS on prednisolone (60 mg/day), oxcarbazepine (450 mg twice daily), and baclofen (10 mg twice daily).

CONCLUSION

Isolated PTS serves as a potential harbinger of NMOSD, and early diagnosis and precise immunotherapy enables rapid symptom control and attack prevention.