1 Division of Nephrology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
2 Division of Radiology, Tri-Service General Hospital Keelung Branch, Taipei, Taiwan.
3 Division of Rheumatology, Immunology and Allergy, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, and Department of Pathology, University of Washington, Seattle, Washington, USA. jameslutaiwan@gmail.com chunchi@uw.edu.