Department of Laboratory Medicine and Pathology (EO, DD, EPF, AZ, SJP, AM), Mayo Clinic, Rochester, MN; Department of Neurology (CV-S, NZ), Mayo Clinic, AZ; Department of Neurology (JB, DD, EPF, AZ, SJP, AM), Mayo Clinic, Rochester, MN; and Department of Neurology (ASL-C), Mayo Clinic, FL.