Multidisciplinary Diabetes Foot Ulcer Service, Fiona Stanley Hospital, Murdoch, Australia.
Department of Endocrinology, Fiona Stanley Hospital, Murdoch, Australia.
J Foot Ankle Res. 2022 Aug 20;15(1):64. doi: 10.1186/s13047-022-00563-2.
Trans-phalangeal and trans-metatarsal amputation, collectively termed 'minor amputations' are important procedures for managing infections of diabetes-related foot ulcers (DFU). Following minor amputation, international guidelines recommend a prolonged course of antibiotics if residual infected bone on intra-operative bone samples are identified, but the quality of the evidence underpinning these guidelines is low. In this study, we examined the concordance of microbiological results from proximal bone cultures compared to results from superficial wound swabs in relation to patient outcomes; with the aim of determining the utility of routinely obtaining marginal bone specimens.
Data was retrospectively collected on 144 individuals who underwent minor amputations for infected DFU at a large Australian tertiary hospital. Concordance was identified for patients with both superficial wound swabs and intra-operative bone samples available. Patient outcomes were monitored up to 6 months post-amputation. The primary outcome was complete healing at 6 months; and secondary outcome measures included further surgery and death. Mann Whitney U testing was performed for bivariate analyses of continuous variables, Chi-Squared testing used for categorical variables and a logistic regression was performed with healing as the dependent variable.
A moderate-high degree of concordance was observed between microbiological samples, with 38/111 (35%) of patients having discordant wound swab and bone sample microbiology. Discordant results were not associated with adverse outcomes (67.2% with concordant results achieved complete healing compared with 68.6% patients with discordant results; P = 0.89). Revascularisation during admission (0.37 [0.13-0.96], P = 0.04) and amputation of the 5th ray (0.45 [0.21-0.94], P = 0.03) were independent risk factors for non-healing.
There was a moderate-high degree of concordance between superficial wound swab results and intra-operative bone sample microbiology in this patient cohort. Discordance was not associated with adverse outcomes. These results suggest there is little clinical utility in routinely collecting proximal bone as an adjunct to routine wound swabs for culture during minor amputation for an infected DFU.
经跖骨和经跖骨的截肢，统称为“小截肢”，是处理糖尿病相关足部溃疡（DFU）感染的重要手术。在小截肢后，如果术中骨样本中存在残留感染骨，国际指南建议延长抗生素治疗疗程，但支持这些指南的证据质量较低。在这项研究中，我们检查了与患者预后相关的近端骨培养的微生物学结果与浅表伤口拭子结果的一致性，目的是确定常规获取边缘骨标本的效用。
回顾性收集了在澳大利亚一家大型三级医院接受小截肢治疗感染性 DFU 的 144 名患者的数据。确定了具有浅表伤口拭子和术中骨样本的患者的一致性。对患者进行了 6 个月的截肢后监测。主要结果是 6 个月时完全愈合；次要结果包括进一步手术和死亡。对连续变量进行双变量分析时采用 Mann Whitney U 检验，对分类变量采用卡方检验，对愈合作为因变量进行逻辑回归。
观察到微生物样本之间具有中度高度一致性，38/111（35%）名患者的伤口拭子和骨样本微生物学不一致。不一致的结果与不良结果无关（35%的结果一致的患者中 67.2%达到完全愈合，而结果不一致的患者中 68.6%达到完全愈合；P=0.89）。住院期间的血运重建（0.37[0.13-0.96]，P=0.04）和第 5 跖骨截肢（0.45[0.21-0.94]，P=0.03）是未愈合的独立危险因素。
在该患者队列中，浅表伤口拭子结果与术中骨样本微生物学之间具有中度高度一致性。不一致与不良结果无关。这些结果表明，在小截肢治疗感染性 DFU 时，常规收集近端骨作为常规伤口拭子培养的辅助手段，临床实用性不大。
