Early operative debridement is a major determinant of mortality in necrotizing fasciitis. However, early recognition is difficult. The aim of our study is to develop a novel scoring system for distinguishing necrotizing fascitis from other soft tissue infections based on routine laboratory findings on admission.

The developmental cohort consisted of 89 consecutive patients with necrotizing fasciitis treated between January 1997 and August 2002. Control patients (n=225) were randomly selected from patients admitted with the diagnosis of cellulitis or abscesses during the same period. Their haematological and biochemical results done on admission were analyzed.

Total white cell count, haemoglobin, sodium, glucose, creatinine and C-reactive protein were selected as predictors. The final constructed model was reliable and discriminated well between patients with necrotizing fascitis from those with other benign soft tissue infections (Area under the receiver-operating characteristic (ROC) curve, 0.98). The LRINEC score was derived from this model and was validated in a separate cohort of patients from a different hospital (56 patients with necrotizing fasciitis and 84 control patients). Based on the calculated probability we stratified patients with soft tissue infections into 3 risks categories: high (LRINEC score _8), intermediate (LRINEC score 6–7) and low (LRINEC score _ 5) risks groups.

The LRINEC score is a robust score capable of detecting even clinically early cases of necrotizing fasciitis. On admission, patients in the intermediate and especially the high risks groups should be subjected to a frozen section biopsy or MRI scans with an aim of early diagnosis, debridement and ultimately