Department of Internal Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Diabetes Technol Ther. 2012 Aug;14(8):669-74. doi: 10.1089/dia.2012.0039. Epub 2012 Jun 12.
This study assessed the utility of pus, soft tissue, and bone specimens in diagnosing diabetic foot infections and the spectrum of the microbial flora and in vitro susceptibility to antibiotics.
This prospective study was carried out in 60 consecutive patients with diabetes having clinically infected foot ulcers. Detailed history, physical examination, and investigation were carried out to diagnose the presence of osteomyelitis and the microbial etiology of foot ulcers. Foot ulcers were classified as per Wagner's classification. Soft tissue, pus, and bone samples were obtained and cultured for aerobic and anaerobic bacteria, and antimicrobial susceptibility testing was carried out as per the standard protocol.
Causative bacteria were isolated in 55 of 60 patients, and 157 isolates were cultured from 117 specimens with an average of 1.34 isolates per cases; however, the number of isolates per specimen did not differ among the various types of samples (P=0.78). Pus and soft tissue had predominantly polymicrobial flora, whereas bone infections were monomicrobial. The isolates from soft tissue specimens were different from those from bone and pus in 57% and 54% of cases, respectively. The common bacterial isolates from 117 specimens included Escherichia coli (21%) and Proteus species (15.9%). Nearly 70% of Staphylococcus aureus isolates were methicillin sensitive. All S. aureus and Enterococcus isolates were sensitive to vancomycin. Susceptibility of Gram-negative organisms to ciprofloxacin was 50%.
Diabetic foot infections are mostly polymicrobial with Gram-negative predominance. Multiple sampling from superficial and deep tissues, including bone, when involved, yields more relevant information diagnostically and therapeutically.
本研究评估了脓液、软组织和骨标本在诊断糖尿病足感染中的作用，以及微生物菌群的分布和体外抗生素敏感性。
本前瞻性研究纳入了 60 例连续的糖尿病合并临床感染性足部溃疡患者。详细的病史、体格检查和调查用于诊断骨髓炎的存在和足部溃疡的微生物病因。根据 Wagner 分类法对足部溃疡进行分类。采集软组织、脓液和骨标本进行需氧和厌氧菌培养，并按照标准方案进行抗菌药物敏感性试验。
在 60 例患者中，有 55 例培养出了病原菌，从 117 个标本中培养出了 157 株，平均每例 1.34 株；然而，各种类型标本的分离株数量无差异（P=0.78）。脓液和软组织主要为混合菌群，而骨感染为单一菌群。软组织标本的分离株与骨和脓液标本的分离株在 57%和 54%的情况下不同。117 个标本中常见的细菌分离株包括大肠杆菌（21%）和变形杆菌属（15.9%）。近 70%的金黄色葡萄球菌分离株对甲氧西林敏感。所有金黄色葡萄球菌和肠球菌分离株均对万古霉素敏感。革兰氏阴性菌对环丙沙星的敏感性为 50%。
糖尿病足感染主要为混合菌群感染，以革兰氏阴性菌为主。当涉及到深部组织（包括骨骼）时，从浅表和深部组织进行多次采样可以提供更具诊断和治疗意义的信息。
