Abstract:

 [Abstract]   Objective   To investigate the clinical features and antibiotic susceptibility of osteomyelitis infected by
Gram-negative bacteria (G^-)in patients suffered from diabetic foot ulcers (DFU).   Methods  The clinical data of 91 DFU patients accompanied with osteomyelitis (DFO) were retrospective studied. These patients hospitalized in the Tianjin Metabolic Diseases Hospital were divided into two groups, Gram-negative bacteria (G^-)group (n=44) and Gram-positive bacteria (G⁺) group (n=42), respectively. The clinical features were compared between two groups. Logistic regression analysis was used to determine the risk factors for Gram-negative bactreial infection. The Gram-negative antibiogram was summarized.  Results   A total of112pathogens were isolated from91patients. G^- bacteria were the most frequent pathogens (48.2%), following by G⁺ bacteria (47.3% ) and fungi (4.5% ).Pseudomonas aeruginosawas the majority of the G^-bacteria. Comparing the two groups, the rate of antibiotic use within the previous6months was significantly higher in G^- group (75.0%) than that of G⁺group (52.4%,P＜0.05). There were no significant differences in the other indicators between two groups. The Logistic regression analysis revealed that the history of antibiotic use was the independent risk factor of G^-bacterial infections in DFO patients. Antibiotics susceptibilities reflected G^-bacteria were more prevalent to resist to cephalosporins and quinolonem, but sensitive to imipenem, ceftazidine and cefperazone-sulbactam.  Conclusion   Gram negative bacteria were not only the main pathogens isolated from DFO patients, but also frequently resistant to several popular antibiotics in China. The proper bacteria culture and antibiotic sensitivity test are especially emphasized to patients with DFU.

Key words: diabetic foot, osteomyelitis, Gram-negative bacterial infections, microbial sensitivity tests, drug resistance