Necrotizing fasciitis: Usefulness of the LRINEC score in a third-level hospital

•The LRINEC score may be useful to aid diagnosis.•A LRINEC low score does not exclude NF.•The average LRINEC score was greater in the cases that required amputation.•Mortality was preceded by septic shock in all cases. To review patients seen in the emergency room, diagnosed with necrotizing fasciitis (NF) and the correlation of such complications with the Laboratory Risk Indicator for Necrotizing fasciitis scale (LRINEC). The purpose of this study is to assess the use of the LRINEC score for early diagnosis of NF and its prognostic use in a consecutive series of cases treated at our hospital. Retrospective observational study including patients with a diagnosis of NF in the emergency room of a tertiary hospital over 11 years. The results are shown as median, interquartile range and absolute range for quantitative variables. In the case of qualitative variables, the results are shown as absolute and relative frequency. The comparison between the categories of the LRINEC scale was performed through a post-hoc comparison from a non-parametric rank-ANOVA analysis. Comparisons between LRINEC groups in the qualitative variables were performed using Fisher’s exact test. A total of 45 patients with a mean age of 51 years were identified. There was a 20% mortality rate (9 cases). The highest mortality rate was registered in the high-risk group (LRINEC greater than 8) with 4 deceased individuals (44.44%), while in the low and moderate-risk groups, 3 and 2 deceased individuals (33% and 22%) were registered, respectively, without considering this result statistically significant (p=0.811). There was an amputation rate of 15.6% (7 cases). The average LRINEC score was greater in the cases that required amputation 9 (95% CI 7; 13) in comparison to the other patients, 6 (95% CI 5; 8), p=0.044. The average hospital stay lasted 32.5 days (95% CI: 25; 40); 30 days in the low-risk group, 41 days in the moderate-risk group and 40 days in the high-risk group. Mortality was associated to a smaller number of interventions (p=0.005) and was preceded by septic shock in all cases. The LRINEC score may be useful to aid diagnosis. However, clinical suspicion is the most important in diagnosis. A LRINEC low score does not exclude NF. In this retrospective series, 35.71% of cases presented a low LRINEC score, making the rate of false negatives high. In view of these results, The LRINEC score cannot be used as a prognostic value since an initial low score does not rule out serious evolu