Abstract: Objective To explore the distribution and antibiotic resistance of pathogens in lesions of diabetic foot osteomyelitis
(DFO) and analyze the risk factors causing osteomyelitis. Methods A total of 372 patients with diabetic foot infections
hospitalized between January 2011 and December 2014, including 203 with osteomyelitis (OM group) and 169 without
osteomyelitis (non-OM group), were examined for the distribution and antibiotic resistance profile of the pathogens in the
wounds. Logistic regression analysis was used to analyze the risk factors causing osteomyelitis. Results Gram-negative
bacteria were the predominant pathogens (53.7%) in the infected wounds in OM group, whereas Gram-positive bacteria were
the most frequently found (56.7%) in non-OM group (P=0.001). Among the Gram-positive bacteria, Staphylococcus was the
dominating flora (35.1%). The resistance rate to oxacillin and cefoxitin of the isolated bacteria in OM group (64.9% and 68.5%,
respectively) was significantly higher than that in non-OM group (29.2% and 32.6% , respectively; P<0.05). Among the
gram-negative bacteria, Enterobacteriaceae was the dominating flora (62.4%), with a higher resistance rate to Cefepime and
Aztreonam in OM group (30.1% and 38.6%, respectively) than in non-OM group (15.1% and 22.2%, respectively; P<0.05).
Logistic regression analysis indicated that the infection by multi-drug resistant bacteria and an wounds area >4 cm2 were the
risk factors for osteomyelitis in patients with diabetic foot infections (P<0.05). Conclusions In addition to an empirical
anti-infection therapy, clinicians should choose specific antibiotics against Gram-negative bacteria according to the microbial
spectrum and antibiotic resistance of pathogens in patients with DFO; patients with diabetic foot infections by multi-drug
resistant bacteria and those with a wound area exceeding 4 cm2 are exposed to an increased risk of osteomyelitis.