1. Department of Dermatology, University of Texas Southwestern Medical Center, Dallas
2. Department of Dermatology, University of Virginia Health System, Charlottesville
3. Department of Dermatology, University of Pennsylvania Health System, Philadelphia
4. Department of Pathology, Pennsylvania Hospital, Philadelphia
5. DDL Diagnostic Laboratory BV, Rijswijk, the Netherlands
6. DDL Diagnostic Laboratory BV, Rijswijk, the Netherlands6Department of Dermatology, Leiden University Medical Center, Leiden, the Netherlands
7. Division of Infectious Diseases, Pennsylvania Hospital, University of Pennsylvania Health System, Philadelphia