10. UTI in elderly subjects can present with constitutional symptoms rather than those localized to the urinary tract, and the fever response can be blunted in the elderly. Symptomatic UTI will be defined as the presence of significant bacteriuria (>102 cfu/ml), pyuria (>10 WBC/hpf) plus > 1 of the following signs and symptoms: fever (> 100.0 F), suprapubic or flank discomfort, bladder spasm, malaise, altered functional status, or altered mental status, provided that no other etiologies for these clinical manifestations can be identified. Subjects' baseline incidence of UTI in the year prior to enrollment will be determined by chart review. Any documented treatment for UTI will be regarded as a symptomatic UTI. We will also inquire whether patients were treated for UTI at an outside facility. Subjects who develop symptomatic UTI will be treated with antibiotics guided by susceptibility patterns for the organism(s) grown from urine cultures.