The diabetic foot. Soft tissue and bone infection.

Diabetic patients, as a consequence of various neurologic, vascular, and metabolic perturbations, are at high risk for developing infections of the soft tissue and bones of the feet. The microbial etiology of soft tissue in infections is best determined by cultures of a tissue curetting or aspiration, rather than a swab. Aerobic gram-positive cocci are the major pathogens in diabetic foot infections; these may be the sole isolate(s) in acute uncomplicated infections, but they are usually accompanied by aerobic gram-negative bacilli or anaerobes in chronic or previously treated infections. Carefully selected patients with mild infections can be treated as outpatients with oral antibiotics, but others require hospitalization and broad-spectrum parenteral antibiotics. Bone infections are frequently diagnosed on the basis of roentgenographs and nuclear medicine scans, but these methods are often inaccurate, and bone cultures should be obtained whenever possible.