Outcomes of Osteomyelitis in Patients Hospitalized With Diabetic Foot Infections

Abstract

Background: This study was conducted to evaluate the outcomes of patients with diabetic foot osteomyelitis (DFO) compared to diabetic foot soft tissue infections (STIs). Methods: 229 patients who were hospitalized with foot infections were retrospectively reviewed, identifying 155 patients with DFO and 74 patients with STI. Primary outcomes evaluated were the rates of amputations and length of hospital stay. DFO was confirmed by the presence of positive bone culture and/or histopathology. Results: Patients with DFO had a 5.6 times higher likelihood of overall amputation ( P < .0001), a 3.4 times higher likelihood of major amputation ( P = .027) and a 4.2 times higher likelihood of minor amputation ( P < .0001) compared to patients without DFO. Major amputation was performed in 16.7% patients diagnosed with DFO and 5.3% of patients diagnosed with STI. Patients with DFO complicated by Charcot neuroarthropathy had a 7 times higher likelihood of undergoing major amputation (odds ratio 6.78, 95% confidence interval 2.70-17.01, P < .0001). The mean hospital stay was 7 days in DFO and 6 days in patients with DFI ( P = .0082). Patients with DFO had a higher erythrocyte sedimentation rate (85 vs 71, P = .02) than patients with STI, however the differences in C-reactive protein (13.4 vs 11.8, P = .29) were not significantly different. Conclusion: In this study of moderate and severe DFIs, the presence of osteomyelitis resulted in a higher likelihood of amputation and longer hospital stay. Readers should recognize that the findings of this study may not be applicable to less severe cases of DFO that can be effectively managed in an outpatient setting. Level of Evidence: Level III, retrospective comparative case series.