MOG and myeloid sarcoma: 26, Table 2) as “unlikely” with a single positive test result (FACS), but a negative pretest (FACS) and post‐test (EUROIMMUN) for MOG‐IgG and the additional red flag “lesions suggestive of MS.” This single patient is formally not consistent with the definitions given above as the intermittent FACS result was indicated as positive, not borderline.