When is plasma exchange indicated over IVMP in NMOSD?

PLEX is preferred for: severe attack (nadir EDSS >6, blindness, complete paraplegia), failure to respond to IV methylprednisolone 1g/day × 5 days within 2 weeks, or attacks in patients on chronic immunosuppression who had breakthrough disease. PLEX achieves improvement in 55–80% of steroid-refractory attacks.

How quickly should NMOSD attacks be treated?

Immediate treatment is critical—attacks may cause irreversible disability within days. IVMP 1g/day × 3–5 days should be initiated within 24 hours of symptom onset. PLEX should be started within 20 days of attack onset for optimal response. Each attack in AQP4-NMOSD may be permanently disabling.

NMOSD Attack Severity Score

Score NMOSD relapse severity using visual acuity, EDSS change, nadir EDSS, lesion length on MRI, and time to peak deficit to guide IV methylprednisolone vs plasma exchange therapy.

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NMOSD AQP4 Probability

Medical Long-tail

NMOSD Attack Severity Score

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Frequently Asked Questions

When is plasma exchange indicated over IVMP in NMOSD?

How quickly should NMOSD attacks be treated?