What is the formula to calculate the Lille score (Liver Disease severity score)?

Calculating the Lille Score

The Lille score is calculated using the formula: R = 3.19 – 0.101 × age (years) + 0.147 × albumin day 0 (g/L) + 0.0165 × (bilirubin day 0 – bilirubin day 7 in μmol/L) – 0.206 × renal insufficiency – 0.0065 × bilirubin day 0 (μmol/L) – 0.0096 × prothrombin time (seconds), then Lille score = exp(–R) / [1 + exp(–R)]. 1

Formula Components

The Lille model integrates six variables measured at baseline (day 0) and one dynamic variable at day 7: 1

• Age in years (coefficient: -0.101)
• Albumin at day 0 in g/L (coefficient: +0.147)
• Bilirubin at day 0 in μmol/L (coefficient: -0.0065)
• Prothrombin time in seconds (coefficient: -0.0096)
• Renal insufficiency: coded as 0 if creatinine <1.3 mg/dL or 1 if ≥1.3 mg/dL (coefficient: -0.206) 1
• Evolution in bilirubin level: calculated as bilirubin day 0 minus bilirubin day 7 in μmol/L (coefficient: +0.0165) 1

Calculation Steps

1. Collect baseline data (day 0) before initiating corticosteroid therapy: age, albumin, bilirubin, prothrombin time, and serum creatinine 1

2. Measure bilirubin at day 7 of corticosteroid treatment 1

3. Calculate the change in bilirubin: subtract day 7 bilirubin from day 0 bilirubin (both in μmol/L) 1

4. Code renal insufficiency: assign 0 if creatinine <1.3 mg/dL, or 1 if ≥1.3 mg/dL 1

5. Calculate R value using the formula with all six variables 1

6. Convert R to Lille score using the logistic transformation: exp(–R) / [1 + exp(–R)] 1

Clinical Application and Timing

The Lille score must be calculated on the seventh day of corticosteroid treatment to identify patients not responding to therapy. 1 This timing is critical because it assesses early improvement in liver function within the first week, which is a predictor of short-term survival. 1

Some evidence suggests the Lille score could be calculated at day 4 with similar prognostic performance, though this requires further validation. 1, 2 In one study, 90.3% of patients were correctly identified as responders or non-responders by day 4 compared with day 7. 2

Score Interpretation

The Lille score ranges from 0 to 1 and stratifies patients into response categories: 1

• Complete responders: Lille score ≤0.16 (91.1% 28-day survival) 1
• Partial responders: Lille score 0.16-0.56 (79.4% 28-day survival) 1
• Null responders: Lille score ≥0.56 (53.3% 28-day survival) 1

Patients with a Lille score ≥0.45 are considered treatment non-responders with 6-month survival of only 20-30%, compared to 70-80% for responders (score <0.45). 1 This cutoff identifies approximately 75% of observed deaths. 3

Clinical Decision-Making

Corticosteroid therapy must be stopped in patients with a Lille score ≥0.56 (null responders), as corticosteroid therapy is as effective as placebo in this subgroup. 1 For patients with scores between 0.45 and 0.56, the decision to continue corticosteroids should be considered case-by-case. 1

The Lille model has superior prognostic accuracy compared to other scoring systems, with an area under the ROC curve of 0.89 in the derivation cohort and 0.85 in validation, significantly higher than Child-Pugh (0.62), Maddrey (0.66), MELD (0.72), or Glasgow scores (0.67). 3

Practical Considerations

Combining the Lille and MELD scores provides the optimal approach for evaluating short- and medium-term risk of death. 1 This combined model enables continuous mortality risk prediction that integrates both the severity of liver impairment at admission and its early improvement during treatment. 1, 4 The MELD+Lille combination performs better than Maddrey+Lille or ABIC+Lille combinations. 4

An online calculator is available at http://www.lillemodel.com for ease of calculation. 1