About the LRINEC score
The LRINEC (Laboratory Risk Indicator for Necrotizing Fasciitis) score is a clinical scoring system published by Wong and colleagues in 2004. It combines six routine blood test results into a single number from 0 to 13 that flags patients whose presentation may be more consistent with necrotizing fasciitis - a rapidly progressive, life-threatening soft-tissue infection - rather than a simple cellulitis or abscess.
How the score is calculated
Each of six laboratory values contributes points based on fixed cutoffs:
- C-reactive protein (CRP): 0 points below 150 mg/L, 4 points at 150 mg/L or higher.
- White blood cell count (WBC): 0 points below 15 x10^9/L, 1 point from 15 to 25, 2 points above 25.
- Hemoglobin: 0 points above 13.5 g/dL, 1 point from 11 to 13.5, 2 points below 11.
- Sodium: 0 points at 135 mmol/L or above, 2 points below 135.
- Creatinine: 0 points at 1.6 mg/dL or below, 2 points above 1.6.
- Glucose: 0 points at 180 mg/dL or below, 1 point above 180.
Adding the six component scores gives the total LRINEC score.
Interpreting the result
A total of 5 or less is low risk, with a reported probability of necrotizing fasciitis under 50 percent in the original derivation cohort. A total of 6 or 7 is intermediate risk, roughly 50 to 75 percent. A total of 8 or higher is high risk, with a reported probability above 75 percent. These are population-level bands from the derivation and later validation studies, not a diagnosis for any one patient.
When to consult a professional
The LRINEC score was designed as a screening aid, not a substitute for clinical judgment. A low score does not rule out necrotizing fasciitis, and surgical exploration remains the definitive step when suspicion is high. Any concern for a rapidly spreading, severely painful, or systemically toxic soft-tissue infection needs urgent evaluation by a clinician, since necrotizing fasciitis can progress within hours.