[1] HARVARD UNIV, SCH MED, DEPT RHEUMATOL & IMMUNOL, BOSTON, MA 02115 USA
[2] TUFTS UNIV, SCH MED, DEPT MED, BOSTON, MA 02111 USA
[3] ST ELIZABETH HOSP, PULM MED UNIT, BOSTON, MA USA
[4] UNIV SO CALIF, SCH MED, DERMATOL SECT, LOS ANGELES, CA 90033 USA