[1] UMHS, Ann Arbor VA Med Ctr, Ann Arbor, MI 48109 USA
[2] UMHS, Dept Internal Med, Div Gen Med, Ann Arbor, MI USA
[3] UMHS, Ann Arbor, MI USA
[4] Univ Michigan, Med Ctr, Off Clin Affairs, Ann Arbor, MI 48109 USA
[5] Dept Infect Control & Epidemiol, Div Infect Dis, Ann Arbor, MI USA
[6] Dept Internal Med, Ann Arbor, MI USA