Wound cultures should not be routinely performed. All pressure sores are colonized and surface culture does not correlate with deep pathogenic organisms. When a clean ulcer base has been attained debridement is discontinued. Unfortunately the two controlled trials supporting this last fact did not control for nutritional factors. Approximately one-half of episodes of bacteremia associated with decubitus ulcers are directly attributed to the ulcer.
Ulcers are usually multiple and purulent though second site of infection is common.
Mortality and morbidity is very high. When response to local therapy of a pressure sore is poor, osteomyelitis should be entertained in the differential diagnosis. Though radionuclide studies are very sensitive they carry a high false positive rate and may be misleading. It is often difficult to confirm an osteomyelitis with a bone biopsy for histology and culture. Presumptive treatment should be directed towards gram positive cocci, gram negative rods and auaeorobes.