Table 3.

Case #2 and Case #3.

A 33-year-old woman with one prior optic neuritis in the right eye with poor recovery (confirmed by an ophthalmologist). Currently, she consults for moderate weakness in both legs (asymmetric with left predominance) associated with sphincter disorders that was confirmed by the neurologist during examination. No other sign and symptoms. Brain MRI shows a short canalicular lesion in the right ON in T2 without gadolinium enhancing and brain was normal. Cervical and thoracic spinal cord MRI show a thoracic T2 lesion from T3 to T4 (central in the axial plane) with gadolinium enhancement at T3.
Should the patient be tested for AQP4-IgG?, n (%) No, this patient does not have a core clinical characteristic of NMOSD. Yes, this patient had a history of a core clinical characteristic of NMOSD and she now has clinically and radiologically a short-transverse myelitis, which does not rule out NMOSD. This patient has a short-transverse myelitis on spinal MRI, which rules out NMOSD. No, this patient had a history of ON typical of MS and she now has clinically and radiologically a short-transverse myelitis, which rules out NMOSD. Not reported	7 (6.6) 92 (86.8) 3 (2.8) 3 (2.8) 1 (0.9)
A 26-year-old woman with no relevant medical history of prior diseases. She developed intractable episodic nausea and vomiting that evolved over 3 days. She was evaluated by a gastroenterologist, but no improvement after symptomatic therapy was observed. The patient was treated with intravenous methylprednisolone with complete recovery. Brain MRI shows bilateral lesion involving the dorsal medulla. Cervical and thoracic spinal cord MRI was normal.
Should the patient be tested for AQP4-IgG?, n (%) Yes, this patient has a core clinical characteristic of NMOSD associated with area postrema lesions on MRI. No, this patient does not have a core clinical characteristic of NMOSD, and false positive serological testing is common in this setting. Yes, although this patient does not fulfill criteria for an area postrema syndrome. No, this patient has a typical syndrome of MS.	101 (95.2) 1 (0.9) 3 (2.8) 1 (0.9)

Correct answers to each question are shown in bold.