糖尿病足患者细菌感染特征及其与下肢血管病变程度的关系

Characteristics of bacterial infection and its relationship with vascular lesions in lower limbs of patient with diabetic foot

目的分析糖尿病足感染患者的病原菌感染学特征及其与下肢血管病变程度的关系。方法收集2009年至2014年我科收治的糖尿病足伴感染患者103例。住院期间所有患者行双下肢CTA或下肢血管造影检查,按照泛大西洋学会联盟(Trans-Atlantic Inter-Society Consensus,TASC)分级(A^D级)把患者分为4组。收集足溃疡分泌物培养及药敏实验结果,运用多样本χ2检验分析不同TASC组间的病原学特征及耐药情况是否存在差异。运用单因素方差分析明确TASC组间的临床基本情况(如年龄、糖尿病病程、糖尿病足病程等)、实验室相关检查指标(如ABI、TBI、白细胞计数、中性粒百分数、血脂等)是否存在差异。结果 TASC分级各组间比较年龄、糖尿病病程、ABI、TBI、中性粒百分数存在明显差异(P分别为0.000、0.001、0.000、0.006、0.039)。所有足溃疡中轻度感染例38例(36.9%),中度感染46例(44.7%),重度感染19例(18.4%)。感染类型中单一革兰阳性菌感染占29.6%、革兰阴性菌感染占27.1%、真菌感染占4.8%;混合感染占38.5%。培养出139株病原菌,其中金黄色葡萄球菌24株(17.3%);铜绿假单胞菌17株(12.2%);粪肠球菌10株(7.2%),分列前3位。TASC组间比较中,随着下肢血管病变程度的加重,混合感染比例逐渐提升,混合感染的比例存在显著差异(P=0.004),在D级患者中混合感染例数占66.7%。结论混合感染与糖尿病足下肢血管病变程度明显相关,随着下肢血管病变程度的加重,混合感染比例逐渐增高。

Objective To investigate the characteristics of bacterial infection and its relationship with vascular lesions in lower limbs of patients with diabetic foot. Methods Totally 103 patients with diabetic foot admitted in our department from 2009 to 2014 were enrolled in this study. All patients received bilateral lower limbs CT angiography（ CTA） or lower limb angiography during the period of hospitalization,and then were divided into 4 groups（ grade A to D） according to the scale of Trans-Atlantic Inter-Society Consensus（ TASC）. Secretions of diabetic foot ulcers were collected for culturing and drug susceptibility test. Chi square test was used to analyze the possible differences in the pathogen features and drug resistance among the 4different TASC groups. One-way analysis of variance（ ANOVA） was employed to detect the relevant factors（ such as age,diabetes duration and course of diabetic foot,etc） and laboratory indexes [including anklebrachial index（ ABI）,toe-brachial index（ TBI）,white blood cell count,neutrophil percentage and blood lipids,etc] on the differences among the different 4 TASC groups. Results There were significant differences in age,diabetes duration,ABI,TBI,and neutrophil percentage among the 4 TASC groups（ P =0. 000,0. 001,0. 000,0. 006 and 0. 039 respectively）. There were 38 patients suffering from mild infections（ 36. 9%）,46 moderate infection（ 44. 7%）,and 19 severe infection（ 18. 4%）. Secretion culturing and drug susceptibility test showed that gram-positive bacteria infections accounted for 29. 6%,gram-negative bacterial infections for 27. 1%,fungal infection for 4. 8%,and mixed infections for 38. 5%. Among the 139 strains of pathogenic bacteria derived from the secretion cultures,the top 3 bacteria were 24 strains of Staphylococcus aureus（ 17. 3%）,17 strains of Pseudomonas aeruginosa（ 12. 2%） and 10 strains of Enterocoecus faecalis（ 7. 2%）. With the severity of vascular lesions in lower limbs,there were more mixed infections,covering significant higher percentage than other infections（ P = 0. 004）. The mixed infection cases accounted for 66. 7% in the patients at TASC grade D. Conclusion Mixed infections are significantly associated with the severity of lower limb vascular lesions in diabetic foot. With the deterioration of the vascular lesion,the percentage of mixed infection is gradually increased. Revascularization can reduce mixed infection,and is helpful in improving the anti-infection treatment in the patients with diabetic foot.