A 70-year-old man was admitted to the hospital because of weight loss, night sweats, and a continuous high-grade fever of 2 months' duration. His past medical history was unremarkable, except for pulmonary tuberculosis treated 55 years earlier and chronic glaucoma. He lived in a rural area and had rare contact with cattle. On admission, his body temperature was 39.5 C; his right laterocervical lymph nodes were enlarged (3 cm x 4 cm) and inflamed. Blood values were unremarkable except for an elevated C-reactive protein level of 150 mg/L (normal<6). A computed tomography scan of the chest showed hilar calcifications and enlarged mediastinal lymph nodes. A biopsy of cervical lymph nodes indicated granulomatous lymphadenitis with foci of necrosis. C. burnetii DNA was detected on the lymph nodes with a C. burnetii-specific pair of primers that amplified an htpAB-associated repetitive element. Results of serologic testing by indirect immunofluorescence (IF) were positive for C. burnetii with immunoglobulin (Ig) G antibody titer to phase 1 and phase 2 antigen of 800 and 1,600, respectively, and IgM antibody titer to phase 2 antigen of 50.