The Laboratory Risk Indicator for Necrotizing Fasciitis was published in 2004. A score of 6 or more should raise suspicion and 8 or more is strongly predictive, but a low score does not rule out necrotising fasciitis – clinical suspicion should prompt surgical exploration.
How to use the LRINEC Score Calculator
- CRP ≥ 150 mg/L
- White cell count (×10³/µL)
- Haemoglobin (g/dL)
- Sodium < 135 mmol/L
- Creatinine > 1.6 mg/dL (141 µmol/L)
- Glucose > 180 mg/dL (10 mmol/L)
Results update as you type, and every field accepts the units shown in its menu.
How it works
Each answer carries the points shown in the published score. The calculator adds them up and maps the total to the published interpretation.
Scoring table
| Item | Answers and points |
|---|---|
| CRP ≥ 150 mg/L | No = 0; Yes = 4 |
| White cell count (×10³/µL) | Below 15 = 0; 15–25 = 1; Above 25 = 2 |
| Haemoglobin (g/dL) | Above 13.5 = 0; 11–13.5 = 1; Below 11 = 2 |
| Sodium < 135 mmol/L | No = 0; Yes = 2 |
| Creatinine > 1.6 mg/dL (141 µmol/L) | No = 0; Yes = 2 |
| Glucose > 180 mg/dL (10 mmol/L) | No = 0; Yes = 1 |
Inputs explained
| Field | What to enter |
|---|---|
| CRP ≥ 150 mg/L | Choose one: No, Yes |
| White cell count (×10³/µL) | Choose one: Below 15, 15–25, Above 25 |
| Haemoglobin (g/dL) | Choose one: Above 13.5, 11–13.5, Below 11 |
| Sodium < 135 mmol/L | Choose one: No, Yes |
| Creatinine > 1.6 mg/dL (141 µmol/L) | Choose one: No, Yes |
| Glucose > 180 mg/dL (10 mmol/L) | Choose one: No, Yes |
Health note: this calculator is for education and screening only and is not a diagnosis or treatment advice. Discuss your results with a qualified clinician.
Formula
Score = sum of the points for each item
Worked example
Inputs — CRP ≥ 150 mg/L: Yes; White cell count (×10³/µL): 15–25; Haemoglobin (g/dL): Above 13.5; Sodium < 135 mmol/L: No; Creatinine > 1.6 mg/dL (141 µmol/L): No; Glucose > 180 mg/dL (10 mmol/L): No.
Results — LRINEC score = 5 / 13; Risk of necrotising fasciitis = Low (under 50%).
Key terms
- Necrotising fasciitis
- A rapidly spreading, life-threatening soft-tissue infection.
Frequently asked questions
What LRINEC score is high risk?
8 or more.
Can necrotising fasciitis occur with a low score?
Yes – the score misses many cases; trust clinical signs.
What are the warning signs?
Pain out of proportion, rapid spread, skin discolouration, blistering, crepitus and systemic illness.