TY - JOUR
T1 - Predicting necrotising soft tissue infections in people who inject drugs
T2 - Poor performance of the LRINEC score and development of a novel clinical predictive nomogram in a retrospective cohort with internal validation
AU - MacLeod, Caitlin S.
AU - O'Neill, Hannah L.
AU - Shaalan, Ramy
AU - Nagy, John
AU - Flett, Murray M.
AU - Guthrie, Graeme J. K.
AU - McLeod, Graeme
AU - Suttie, Stuart A.
N1 - Copyright:
© 2023 the Author(s). Published by Wolters Kluwer Health, Inc.
PY - 2023/4/13
Y1 - 2023/4/13
N2 - Introduction: 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.Methods: A retrospective database of all hospital admissions due to limb-related complications secondary to injecting drug use between December 2011-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; ANOVA; Kaplan-Meier and receiver operating characteristic curves. Nomograms were developed to facilitate diagnosis and predict survival.Results: There were 557 admissions for 378 patients, with 124 (22.3%; 111 patients) NSTI. Time from admission to: theatre and CT 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 (CRP) and non-linear albumin to be significant predictors of NSTI, with age, white cell count, sodium, creatinine, CRP and albumin being significant in predicting survival on discharge.Conclusion: There was reduced performance of the LRINEC in this PWID cohort. Diagnosis may be enhanced through use of this predictive nomogram.
AB - Introduction: 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.Methods: A retrospective database of all hospital admissions due to limb-related complications secondary to injecting drug use between December 2011-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; ANOVA; Kaplan-Meier and receiver operating characteristic curves. Nomograms were developed to facilitate diagnosis and predict survival.Results: There were 557 admissions for 378 patients, with 124 (22.3%; 111 patients) NSTI. Time from admission to: theatre and CT 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 (CRP) and non-linear albumin to be significant predictors of NSTI, with age, white cell count, sodium, creatinine, CRP and albumin being significant in predicting survival on discharge.Conclusion: There was reduced performance of the LRINEC in this PWID cohort. Diagnosis may be enhanced through use of this predictive nomogram.
KW - Necrotising fasciitis
KW - People who inject drugs (PWID)
KW - Intravenous drug use
KW - Injecting drug use
KW - Substance use
KW - ; Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC)
KW - nonogram
KW - prediction model
KW - necrotising soft tissue infections
U2 - 10.1097/JS9.0000000000000367
DO - 10.1097/JS9.0000000000000367
M3 - Article
C2 - 37042577
SN - 1743-9191
JO - International Journal of Surgery
JF - International Journal of Surgery
ER -