LAUSR

A 63-year-old male farmer experienced right leg pain for 1 year. The pain initially only occurred during activity, but developed into persistent sharp pain. After 1 month of worsening pain, he was admitted to our hospital. On physical examination, the distal right femur was tender, with no warmth or erythema. Routine blood examination results were normal. Radiography (Figure 1a) and computed tomography (Figure 1b) showed expansive bone destruction with surrounding osteosclerosis in the distal right femur. Magnetic resonance imaging showed that the edge of the lesion was “map-like” (Figure 1c). A multidisciplinary team suspected a benign femoral tumor and proposed surgical treatment. However, a radiologist questioned the diagnosis when the patient mentioned that he raised sheep. Further inquiry revealed that the patient kept cattle and sheep and had been diagnosed with brucellosis 7 years previously at a local infectious disease hospital. After antibiotic therapy, he had been considered cured and was intermittently treated with tetracycline. Computed tomography (CT) (Figure 1d) showed old bone destruction of the thoracic vertebrae. He had deliberately hidden his history of brucellosis when he was admitted to our hospital for fear of isolation for a suspected infectious disease. After learning this important personal history, we performed a femoral puncture biopsy. Pathological examination of the femoral puncture biopsy revealed dead bone. A diagnosis of brucellosis was confirmed by a serum agglutination test. After 2 months of antibiotics and hormone therapy, the