Unreliable diagnostic accuracy of laboratory risk indicator for necrotizing fasciitis (LRINEC) score but good outcome predictor in necrotizing fasciitis due to Vibrio vulnificus: A retrospective and matched-pair study

The diagnostic accuracy of laboratory risk indicator for necrotizing fasciitis (LRINEC) score system in specific Vibrio vulnificus (V vulnificus) necrotizing fasciitis (NF) have not been fully investigated yet. This aim of our study is to validate the LRINEC score in patients with V vulnificus NF. A retrospective study of hospitalized patients was conducted in a hospital in southern Taiwan between January 2015 and December 2022. Clinical characteristics, variables and outcomes were compared among V vulnificus NF, non-Vibrio NF and cellulitis patients. A total of 260 patients were included, 40 in V vulnificus NF group, 80 in non-Vibrio NF group and 160 patients in cellulitis group. In V vulnificus NF group with an LRINEC cutoff score ≥ 6, the sensitivity was 35% (95% confidence interval [CI]: 29%-41%), specificity was 81% (95% CI: 76%-86%), PPV was 23% (95% CI: 17%-27%), and NPV was 90% (95% CI: 88%-92%). The AUROC for accuracy of the LRINEC score in V vulnificus NF was 0.614 (95% CI: 0.592-0.636). Multi-variable logistic regression analysis revealed that LRINEC > 8 was significantly associated with higher in-hospital mortality (adjusted odds ratio = 1.57; 95% CI: 1.43-2.08; P <.01). The LRINEC score may not be an accurate tool for V vulnificus NF. That should be used with caution as a routine diagnostic tool. However, LRINEC > 8 is significantly associated with higher mortality in V vulnificus NF patients.