Maddrey Discriminant Function Calculator (Alcoholic Hepatitis)
Calculate Maddrey’s discriminant function for alcoholic hepatitis from prothrombin time, control PT and bilirubin (mg/dL or µmol/L) — a DF of 32 or more marks severe disease where corticosteroids may help.
How it works
DF = 4.6 × (patient PT − control PT, seconds) + total bilirubin (mg/dL). Bilirubin in µmol/L ÷ 17.1 = mg/dL. DF ≥ 32 = severe alcoholic hepatitis.
Maddrey’s discriminant function (Maddrey et al., Gastroenterology 1978; modified by Carithers 1989) identifies alcoholic hepatitis with a high short-term mortality: without treatment, 1-month mortality with a DF of 32 or more was roughly 30–50%. In that group, guidelines (AASLD, EASL) suggest considering prednisolone 40 mg daily for 28 days if there is no infection, bleeding or kidney failure, and checking the Lille score on day 7 to stop steroids in non-responders. The MELD score (over about 20) is also used to define severe disease.
Worked example
A patient with PT 21 s against a control of 12 s and bilirubin 8 mg/dL has DF = 4.6 × (21 − 12) + 8 = 41.4 + 8 = 49.4 — severe alcoholic hepatitis (DF ≥ 32); corticosteroids may be considered if there is no contraindication.
Sources: Maddrey WC et al. Corticosteroid therapy of alcoholic hepatitis. Gastroenterology 1978 · Crabb DW et al. AASLD practice guidance: alcohol-associated liver disease (2019)
Frequently asked questions
What is a high Maddrey score?
A discriminant function of 32 or more defines severe alcoholic hepatitis with a high risk of death within one to three months; below 32 the short-term prognosis is much better.
Can I use INR instead of PT?
The formula needs the prothrombin time in seconds and the laboratory’s control value. INR is not interchangeable — use MELD if only INR is available.
Should everyone with DF ≥ 32 get steroids?
Not automatically. Infection, gastrointestinal bleeding, kidney failure and other contraindications must be excluded, and the response is checked with the Lille score after 7 days.
How do I convert bilirubin from µmol/L?
Divide by 17.1 to get mg/dL — for example 137 µmol/L ÷ 17.1 ≈ 8 mg/dL. Choose µmol/L in the unit box and the calculator converts it for you.
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Clinical decision tool for education and for use by trained clinicians alongside clinical judgement — not a diagnosis and not a substitute for medical assessment. Scores validated in specific populations may not apply to every patient.