Use AQP4 Antibody Testing in Neuromyelitis Optica Spectrum Disorder to guide the working diagnosis and next step; let the main risk or management issue drive escalation, treatment choice, and follow-up.

Testing should always be performed directly on blood serum, which has proven to be significantly more sensitive than testing the cerebrospinal fluid.; This means that while a negative result cannot completely exclude the condition, a positive antibody test provides ironclad support for the diagnosis.; Highly targeted aquaporin-four cell-based assay yields a sensitivity of about 70%, but its specificity is nearly 100%.; Highly suspect neuromyelitis optica if the individual is of African American, Hispanic, or Asian descent.; Because the antibody can occasionally read as false-negative early on, it is highly prudent to repeat the blood test if your clinical suspicion remains strong.