A 79-year-old man was admitted to a municipal hospital with a bilateral sensory level below T3 and gait ataxia since the last month (EDSS 6.5). Magnetic resonance imaging (MRI) revealed spinal cord lesions at vertebra C1-4, at T3/4, and brain microangiopathy. Cerebrospinal fluid (CSF) analysis showed mildly increased albumin, but normal immunoglobulin G (IgG), negative oligoclonal bands (OCB), and a normal cell count. Autoimmune myelitis was suspected, and symptoms improved after intravenous glucocorticoids (EDSS 5.0).\nFour months later, a second attack occurred with severe left-sided optic neuritis and worsening of sensorimotor symptoms (EDSS 9.0). MRI revealed an enlarged myelon lesion (medulla oblongata to vertebra C5, partially gadolinium-enhancing). CSF analysis showed pleocytosis (32/µl). Symptoms improved after intravenous steroids (EDSS 8.0).\nAfter another month, a third attack occurred with dysphagia, a high-cervical transverse spinal cord syndrome with marked tetraparesis, and another severe optic neuritis (blindness in left eye; EDSS 9.0). He was admitted to a university hospital. MRI revealed a lesion extending over the entire myelon and brainstem involvement (Fig. a). CSF analysis showed 43 cells/µl including granulocytes. AQP4-Ab were positive in serum and CSF (ΔMFI 816 and 181, respectively, FACS-based assay), and diagnosis of AQP4-Ab positive NMO [] as part of NMOSD [] was established. Intravenous steroids were given, followed by plasma exchange, without improvement. After further deterioration with respiratory insufficiency because of high cervical myelon involvement (EDSS 9.5) and pneumonia, he required intensive care and died shortly thereafter.
An 88-year-old woman experienced numbness in her legs and moderate paraparesis with impaired gait since 2 days. Spinal MRI demonstrated a myelon lesion from vertebra T6-9 (Fig. b-c), which was initially attributed to compression myelopathy because of concomitant vertebral disc protrusions. Without specific treatment, she recovered partially and was able to walk with a crutch for >100 m (EDSS 6.0). Her previous medical history was negative for prior potential attacks, but included a transient ischemic attack with dysarthria for <24 h 1.5 years before; cerebral MRI had not shown inflammatory lesions.\nEight months later, she was re-admitted with an anew gait impairment and sensorimotor paraparesis (MRC grade 2–3, EDSS 8.5). MRI demonstrated a new T2 hyperintense myelon lesion from vertebra T10–T12 with central gadolinium enhancement (Fig. d–f). Visual evoked potentials had low amplitudes bilaterally and normal latencies. CSF showed mild lymphomonocytic pleocytosis and positive OCB. Serum AQP4-Ab were positive (1:3200, cell-based immunofluorescence assay), as were antibodies against dsDNA and cardiolipin. Diagnosis of AQP4-Ab positive NMOSD was established, and the first myelon lesion was retrospectively attributed also to NMOSD. Treatment included methylprednisolone 5 × 1 g, a second cycle of 5 × 2 g, and then plasma exchange. She recovered partially (EDSS 7.0). Azathioprine was given up to 150 mg/d (2.2 mg/kg); thiopurine S-methyltransferase activity was normal. After 5 months of therapy, regular blood testing revealed pancytopenia. Azathioprine was stopped, but thrombocytopenia persisted and she died of intestinal bleeding. In addition to azathioprine as a likely cause for bone marrow suppression and thrombocytopenia, she had also developed anti-platelet antibodies.