MC01
Seroconversion of Serum Nmo IgG in Initial Seronegative Nmo IgG and Positive CSF Nmo IgG Antibody Neuromyelitis Optica Case
Neuromyelitis Optica (NMO) is a demyelinating disorder which can cause disabling symptoms. Serum NMO IgG plays an important role in diagnosis of NMO.
Objectives:
We are presenting a patient with NMO with positive CSF (Cerebrospinal Fluid) NMO IgG antibody. Serum NMO IgG antibody was initially negative and became positive 5 months after diagnosis.
Methods:
Chart review.
Results:
41 y/o woman presented with left visual loss and pain on eye movement. A diagnosis of optic neuritis was made, confirmed with MRI (define) orbits. Patient improved with IV methyprednisolone for 5 days. CSF analysis revealed 3 oligoclonal bands, 0.63 CSF iGG index and positive CSF NMO IgG . Blood work, including serum NMO IgG antibody was normal. MRI C spine during the same admission revealed longitudinally extensive transverse myelitis from C2-C5. Repeat Serum NMO IgG after 5 months came back positive with 1:1000 titers.
Conclusions:
This case implies the significance of following up with serum NMO IgG in NMO suspected patients. It highlights the significance of CSF NMO IgG AB in seronegative patients with strong clinical suspicion, to make timely diagnosis. This case is in line with previous articles reporting rare cases of positive CSF NMO IgG in seronegative patients with neuromyelitis optica.