Abstract:Objective To explore the correlation between local characteristics (infection width, infection depth, blood supply) of diabetic foot infection (DFI) and systemic infection indicators of patients. Methods Patients with unilateral DFI but without receiving anti-infective treatment in the department of endocrinology of a hospital from January 2016 to May 2019 were retrospectively included in analysis, white blood cell (WBC), neutrophil (N), C-reactive protein (CRP) were collected as indicators of systemic infection, according to the width of infection, infection was divided into toe involvement only, foot involvement only, toe+metatarsophalangeal joint involvement, and toe+metatarsophalangeal joint+foot involvement. According to the depth of infection, infection was divided into superficial infection (involving only skin and subcutaneous tissue), middle infection (involving muscles and tendons), and deep infection (involving bone and joint). According to the ankle brachial index (ABI) of the affected side, blood supply was divided into normal (ABI≥0.9), mild ischemia (0.4≤ABI<0.9) and severe ischemia (ABI<0.4), multivariate analysis of variance and group comparison were adopted for statistical analysis. Results There was no significant difference in patients' WBC, N and CRP among different width of DFI (P>0.05), group comparison indicated that infection width was positively correlated with WBC, N and CRP when infection was widely involved or very limited. There were significant differences in WBC, N and CRP among different depth of infection (P=0.012, 0.010 and 0.003 respectively), group comparison indicated that infection depth was positively correlated with WBC, N and CRP. There were significant differences in WBC, N and CRP in DFI patients with different blood supply (P=0.003, 0.003 and 0.001 respectively), multiple groups comparisons suggested that degree of ischemia in diabetic foot was negatively correlated with WBC, N and CRP of patients. Conclusion Local characteristics of DFI have an important influence on the indicators of patients' systemic infection. DFI width and depth is positively correlated with patients' systemic infection indicators, but was negatively correlated with ischemia.