Aquaporin-4 Neuromyelitis Optica With Area Postrema Syndrome
A 28-year-old woman presents with 3 days of painful bilateral visual loss, worse on the left, and 1 week of intractable hiccups and vomiting. She had a similar left optic neuritis 2 years ago and recovered after steroids. Visual acuity is 20/200 left and 20/40 right; there is a left afferent pupillary defect and bilateral optic disc swelling. She has reduced vibration and pinprick below T4, brisk reflexes, and bilateral Babinski signs. MRI shows a longitudinally extensive T2 lesion from C3 to T2 and left optic nerve enhancement; brain MRI shows periependymal lesions. Serum aquaporin-4 IgG is positive. She is not pregnant and asks about long-term therapy and whether she can have children. Chest radiograph is normal; varicella and hepatitis B serologies are negative.
1. What is the diagnosis, and how would you treat the acute attack if she does not improve promptly?
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Diagnosis: aquaporin-4-positive neuromyelitis optica spectrum disorder (NMOSD), with left optic neuritis, longitudinally extensive transverse myelitis (C3-T2), area postrema syndrome (intractable hiccups and vomiting), and periependymal brain lesions. The prior optic neuritis and positive AQP4 IgG make this definite; multiple sclerosis is unlikely because of the long cord lesion and area postrema involvement.
Acute treatment: intravenous methylprednisolone 1 g daily for 5 days. Because she has severe visual loss and a long myelitis, do not delay escalation if there is no clear improvement by day 3-5: plasma exchange, typically 5-7 sessions, is the next step. Treat pain and vomiting; monitor for urinary retention and constipation. Avoid: oral tapering steroids alone as definitive attack therapy; they do not prevent relapse.
2. What maintenance therapy would you choose, and which agents should be avoided?
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Maintenance: start a relapse-preventing therapy soon after the attack. Rituximab is widely used and effective; eculizumab and inebilizumab are alternatives for AQP4-positive disease, and azathioprine or mycophenolate are options where access is limited. Choice depends on cost, vaccination status, and monitoring. Check hepatitis B and varicella serology, and vaccinate against meningococcus before eculizumab.
Avoid: interferons, fingolimod, and natalizumab can worsen NMOSD and should not be used. Monitoring: CD19/CD20 counts for rituximab, infusion reactions, and infection risk. Reasoning: NMOSD is antibody-mediated and complement-dependent, so therapies targeting B cells or complement are more rational than MS platform drugs.
3. How would you counsel her about pregnancy, breastfeeding, and vaccination?
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Pregnancy counseling: she can consider pregnancy, but plan it during stable disease. Relapse risk is increased in the first 3-6 months postpartum, so maintenance therapy should be continued or restarted promptly after delivery, with neurology and obstetrics input. Rituximab is often stopped before conception and restarted postpartum; individualize. Vaccinations: give non-live vaccines before anti-CD20 therapy or complement inhibitors; live vaccines are avoided on immunosuppression. Breastfeeding: check the specific agent; rituximab is generally compatible, but specialist advice is needed. Red flags: new hiccups, vomiting, visual loss, or limb weakness requires urgent MRI and attack treatment, not a wait-and-see approach.