Fever of unknown origin in the elderly: lymphoma presenting as vertebral compression fractures.

I n elderly patients, the syndrome of fever of unknown origin (FUO) differs in several important regards from that seen in younger patients. The causes of FUO in the elderly are rarely benign or selflimited; almost always, an elderly patient with FUO will be found to have a serious illness as the cause of the fever.':" Factitious and fraudulent causes of FUO are exceedingly rare in the elderly. 7, 8 We present the cases of two elderly men with FUO, which was ultimately shown to be caused by lymphoma. Both had back pain with vertebral compression fractures relatea to the neoplasms, and initially both were presumed to have these fractures secondary to osteoporosis. This presumption contributed to a delay in diagnosis of the cause of the FUO in both patients.