CSF Autoantibody Panel Test Utilization in Patients Presenting With Neurologic Alterations: A 3-Year Retrospective Study

Abstract Introduction When patients present with a range of neurological symptoms, it can be difficult to identify the cause. CSF evaluation of patients who present with a subacute neurological disorder of undetermined etiology is very helpful, especially in patients with known risk factors for autoimmune neurologic disease or cancer. The goal of this study was to review the results of CSF autoantibody panels ordered over the last 3 years and determine the percentage of panels that were positive. Methods Results of CSF autoantibody panels ordered over the last 3 years were reviewed and the percentage of samples that tested positive and the most common autoantibody was calculated. Conclusion At our institution, pathology residents review orders for CSF autoantibody panel evaluation and approve testing based on the clinical history and neurologic evaluation in order to prevent inappropriate test utilization. Of the 192 CSF evaluations ordered between 2015 and 2018 (5 dementia, 72 encephalopathy, and 115 paraneoplastic CSF-autoimmune evaluation), 19.8% of the tests were positive. The most common autoantibodies detected were the NMDA (4.68%) and VGKC (4.68%) receptors.