AQUAPORIN-4 (AQP-4) IMMUNOGLOBULIN G SEROPOSITIVE NEUROMYELITIS OPTICA: A REVIEW AND CASE REPORT.

Background: Neuromyelitis optica spectrum disorder (NMOSD) is a relatively new terminology composed to encompass patients with neuromyelitis optica (NMO) and related immunological conditions. The diagnosis of this condition requires a seropositive aquaporin-4 immunoglobulin G (AQP-4 IgG), the presence of at least one core clinical characteristic and the exclusion of alternative diagnoses. Very few cases have been reported in sub-Saharan Africa.

Objective: The aim of this article is to report a classical case of NMOSD with AQP-4 IgG seropositivity and normal brain, cervical and thoracic MRI findings.

Result: We report a 25-year-old Nigerian woman who presented with recurrent and alternating weakness, pain and numbness of all limbs, associated with episodic painful left-sided tonic spasms and urinary incontinence. She had earlier had symptoms of recurrent, episodic and alternating loss of vision in both eyes, associated with ocular pain.Examination findings revealed an intact mental status, no cranial nerve deficit and no focal limb weakness. Right-sided deep tendon reflexes were exaggerated. Vital signs were within normal limits. Brain MRI, Cervical spine MRI and Thoracic spine MRI all revealed normal findings. Serum aquaporin-4 IgG assay returned positive with a titer of 1:32.She was commenced on high dose steroids and there was gradual improvement of symptoms.

Conclusion: These findings confirmed the diagnosis of neuromyelitis optica spectrum disorder, and satisfies the diagnostic criteria published in 2015 by the International Panel for NMO Diagnosis (IPND).