East of Scotland Vascular Network, Department of Vascular Surgery.
School of Medicine, University of Dundee, Dundee, Scotland.
Int J Surg. 2023 Jun 1;109(6):1561-1572. doi: 10.1097/JS9.0000000000000367.
Necrotising soft tissue infections (NSTI) can threaten life and limb. Early identification and urgent surgical debridement are key for improved outcomes. NSTI can be insidious. Scoring systems, like the Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC), exist to aid diagnosis. People who inject drugs (PWID) are high risk for NSTI. This study aimed to assess the utility of the LRINEC in PWID with lower limb infections and develop a predictive nomogram.
A retrospective database of all hospital admissions due to limb-related complications secondary to injecting drug use between December 2011 and December 2020 was compiled through discharge codes and a prospectively maintained Vascular Surgery database. All lower limb infections were extracted from this database, dichotomised by NSTI and non-NSTI with the LRINEC applied. Specialty management times were evaluated. Statistical analyses involved: chi-square; Analysis of "variance"; Kaplan-Meier, and receiver operating characteristic curves. Nomograms were developed to facilitate diagnosis and predict survival.
There were 557 admissions for 378 patients, with 124 (22.3%; 111 patients) NSTI. Time from admission to: theatre and computed tomography imaging respectively varied significantly between specialties ( P =0.001). Surgical specialties were faster than medical ( P =0.001). Vascular surgery received the most admissions and had the quickest time to theatre. During follow-up there were 79 (20.9%) deaths: 27 (24.3%) NSTI and 52 (19.5%) non-NSTI. LRINEC ≥6 had a positive predictive value of 33.3% and sensitivity of 74% for NSTI. LRINEC <6 had a negative predictive value of 90.7% and specificity of 63.2% for non-NSTI. Area under the curve was 0.697 (95% CI: 0.615-0.778). Nomogram models found age, C-reactive protein, and non-linear albumin to be significant predictors of NSTI, with age, white cell count, sodium, creatinine, C-reactive protein, and albumin being significant in predicting survival on discharge.
There was reduced performance of the LRINEC in this PWID cohort. Diagnosis may be enhanced through use of this predictive nomogram.
坏死性软组织感染（NSTI）可威胁生命和肢体。早期识别和紧急手术清创是改善预后的关键。NSTI 可能是隐匿的。实验室风险指数坏死性筋膜炎（LRINEC）等评分系统可协助诊断。注射毒品者（PWID）发生 NSTI 的风险较高。本研究旨在评估 LRINEC 在下肢感染的 PWID 中的应用，并建立预测列线图。
通过出院代码和前瞻性维护的血管外科数据库，汇编了 2011 年 12 月至 2020 年 12 月因注射毒品导致的肢体相关并发症的所有住院患者的回顾性数据库。从该数据库中提取所有下肢感染，根据 NSTI 和非 NSTI 进行二分法，应用 LRINEC。评估专科管理时间。统计分析包括：卡方检验；方差分析；Kaplan-Meier 分析和受试者工作特征曲线。建立列线图以协助诊断和预测生存率。
共 557 例患者（378 例），124 例（22.3%，111 例）为 NSTI。从入院到手术室和计算机断层扫描成像的时间，各专科之间差异显著（P=0.001）。外科专业比内科专业快（P=0.001）。血管外科接收的入院人数最多，到达手术室的时间最快。在随访期间，有 79 例（20.9%）死亡：27 例（24.3%）为 NSTI，52 例（19.5%）为非 NSTI。LRINEC≥6 对 NSTI 的阳性预测值为 33.3%，灵敏度为 74%。LRINEC＜6 对非 NSTI 的阴性预测值为 90.7%，特异性为 63.2%。曲线下面积为 0.697（95%CI：0.615-0.778）。列线图模型发现年龄、C 反应蛋白和非线性白蛋白是 NSTI 的重要预测因子，年龄、白细胞计数、钠、肌酐、C 反应蛋白和白蛋白对出院时的生存预测有重要意义。
LRINEC 在本 PWID 队列中的表现有所下降。通过使用此预测列线图，诊断可能会得到改善。
