Capacity Building for the Diagnosis and Treatment of Neuromyelitis Optica using Point of Care Aquaporin-4 Antibody Testing

About This Grant

Neuromyelitis optica (NMO) is an autoantibody-mediated disease of the central nervous system, predominantly affecting women and disproportionately people of African descent. The diagnosis of NMO is contingent upon the accurate detection of the aquaporin-4 (AQP4) antibody, the disease's sensitive and specific biomarker. The availability, accessibility, and affordability of the AQP4 antibody test is low in low- and middle-income countries. Most patients with NMO do not have access to the test globally. Moreover, neuroimmunological disorders have traditionally, but erroneously, been considered to be rare in Black patients, with costly diagnostic tests and even more costly treatments, leading to limited expertise being built in lowest income African settings. Recently, new advances in autoantibody detection using low-cost techniques have emerged, allowing our team to detect the AQP4 antibody from small blood samples that are collected by the patient onto a filter paper-based test and mailed to the processing laboratory. This method allows patients far from reference laboratories to collect a dried blood sample and learn their diagnosis. These samples can be tested from warm temperatures, stored at room temperature, and last months and still be processed successfully. When processed at the Mayo Clinic Laboratories, dried blood spots have a high sensitivity and moderately high specificity for AQP4 detection. The most immediate value for a point of care AQP4 test is in lowest income settings where laboratory capacity is limited and antibody testing is not the current standard of care. In this study, a collaborative team from Massachusetts General Hospital, Mayo Clinic Rochester, and the Ignace Hospital in Guinea with three rural Guinean sites - Dubreka, Fouricariah, and Kindia - will focus on capacity building for neuroimmunological diagnosis and management in the West African Republic of Guinea. The team will test the point of care dried blood spot test in phenotypically-enriched cohorts at highest likelihood of having AQP4 antibody positive NMO in Guinea and estimate point prevalence of NMO in these cohorts. The well-defined subcohort of AQP4+ NMO patients will serve as a base for future clinical trials for the Guinean investigators. The study team will leverage their deep and established expertise to elevate the status of neuroimmunological disease expertise in West Africa. The team will also establish a workflow for testing at the point of care for complex and devastating neuroimmunological diseases, a process that can be eventually scaled for other point of care tests in remote, rural, and/or resource-limited settings.