CALR and syphilis: Laboratory tests demonstrated negative encephalopathy antibody panel in serum (ENS1, Mayo Clinic Laboratories) and CSF (ENC1, Mayo Clinic Laboratories), syphilis screening, p-ANCA, c-ANCA, cryoglobulin, anti SS-A, SS-B, anti-Smith, erythrocyte sedimentation rate (ESR), antiribonucleoprotein and borrelia screening, and indeterminate atypical ANCA; normal levels of methylmalonic acid, homocysteine, vitamins B1, B2, B5, B6, B9, and B12, arsenic, lead, mercury, cadmium, TPO and TG antibodies, C-reactive protein, thyroid stimulating hormone (TSH), and fT3/T4.