1. Dept. of Internal Medicine; National Taiwan University Hospital and National Taiwan University College of Medicine; Taipei Taiwan
2. Clinical Microbiology and Infectious Diseases Dept.; Hospital General Universitario Gregorio Marañón, Spanish Study Group of Infection in Transplant Patients, and CIBER de Enfermedades Respiratorias; Madrid Spain
3. Dept. of Internal Medicine, Division of Infectious Diseases; University of Pittsburgh; Pittsburgh PA 15240