Challenges in Multiple Sclerosis Diagnosis: Misapplication and Misunderstanding of the McDonald Criteria (S6.001)

Objective: To assess proper application of McDonald Criteria key elements among neurology residents and multiple sclerosis (MS) specialists. Background: Studies suggest knowledge gaps for identification of typical MS syndromes, periventricular and juxtacortical MRI lesion locations, and consideration of historical symptoms may cause MS misdiagnosis. Design/Methods: Neurology residents and practicing MS specialists completed a web-based survey by email invitation. Results: 72 residents and 88 MS specialists from the US and Canada participated. MS atypical syndromes that were incorrectly identified as typical included: complete transverse myelopathy (35% residents, 15% MS specialists), intractable vomiting/nausea/hiccups (20% residents, 5% MS specialists), and bilateral optic neuritis/unilateral optic neuritis with poor visual recovery (17% residents, 10% MS specialists). “Touch or abutting” the ventricle criterion for periventricular lesions was correctly identified by 38% of residents and 61% of MS specialists; “juxtacortical” criterion was correctly identified by 19% of residents and 54% of MS specialists. Optic nerve involvement was incorrectly identified as a region for fulfillment of MRI dissemination in space (DIS) by 31% of residents and 26% of MS specialists. Subcortical white matter was incorrectly identified by 11% of residents and 18% of MS specialists as a region for fulfillment of MRI DIS. A Radiologically Isolated Syndrome (RIS) case was incorrectly assigned fulfillment of McDonald Criteria by 48% of residents and 12% of MS specialists. Non-specific historical visual symptoms were considered fulfillment of dissemination in time (DIT) by 75% of residents and 49% of MS specialists, and non-specific historical sensory and coordination symptoms were considered fulfillment of DIT by 88% of residents and 65% MS specialists. Additional case-based and imaging-based responses will be presented. Conclusions: Neurology residents and, to a lesser degree, MS specialists incorrectly identified core components of the MS diagnostic criteria. Educational efforts could potentially reduce misdiagnosis by concentrating on misunderstood and misapplied components of the McDonald Criteria. Disclosure: Dr. Solomon has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Biogen. Dr. Solomon has received research support from Biogen. Dr. Pettigrew has nothing to disclose. Dr. Naismith has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Acorda, Alkermes, Biogen, Celgene, EMD Serono, Genentech, Genzyme, and Novartis. Dr. Naismith has received personal compensation in an editorial capacity as the Associate Editor NEJM Journal Watch. Dr. Naismith has received research support from Acorda, Alkermes, Biogen, Celgene, EMD Serono, Genentech, Genzyme, and Novartis. Dr. Chahin has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Genzyme and Teva. Dr. Krieger has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Acorda, Bayer, Biogen, Celgene, EMD Serono, Genentech, Genzyme, Mallinckrodt, MedDay, Novartis, Teva, and TG Therapeutics. Dr. Weinshenker has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Novartis, Alexion, MedImmune, Caladrius Biosciences, Brainstorm Therapeutics, Chugai, and Roivant Sciences. Dr. Weinshenker has received royalty, license fees, or contractual rights payments from RSR Ltd, Oxford University, Hospices Civil de Lyon, MVZ Labor PD Dr. Volkmann und Kollegen GbR.