Liver & Gastroenterology

Maddrey Discriminant Function Calculator – Alcoholic Hepatitis Severity

Clinical calculation support · Verify results before clinical use

Modified Maddrey Discriminant Function

Enter baseline prothrombin time and total bilirubin to assess alcoholic hepatitis severity.

—mDF score

Alcoholic hepatitis severity classification

—

Clinical interpretation

About the Maddrey Discriminant Function

The Maddrey Discriminant Function (mDF), also known as the modified Maddrey score, is a prognostic tool used to assess disease severity in patients with alcohol-associated hepatitis. It combines prothrombin time prolongation and serum bilirubin.

Calculation formula

mDF = 4.6 × (Patient PT − Control PT) + Total Bilirubin (mg/dL)

When bilirubin is entered in µmol/L, the calculator converts it to mg/dL before applying the formula. Both PT values must be entered in seconds.

Interpretation

mDF score	Severity classification	Clinical meaning
<32	Not classified as severe by mDF	Does not meet the mDF severe threshold.
≥32	Severe alcoholic hepatitis	Associated with increased short-term mortality risk; requires specialist clinical assessment.

Important clinical considerations

The mDF is a severity and prognostic score, not a diagnostic test for alcohol-associated hepatitis.
The 1989 pivotal trial also enrolled patients with spontaneous hepatic encephalopathy regardless of discriminant function value.
The ACG 2024 guideline identifies MELD >20 as a severity threshold and notes advantages of MELD, including INR and serum creatinine.
An mDF result should not be used alone to determine corticosteroid treatment. Evaluate contraindications, infection, renal function, bleeding, and the overall clinical context.

References

Maddrey WC, Boitnott JK, Bedine MS, Weber FL Jr, Mezey E, White RI Jr.Corticosteroid therapy of alcoholic hepatitis. Gastroenterology. 1978;75(2):193–199. DOI: 10.1016/0016-5085(78)90401-8.

Carithers RL Jr, Herlong HF, Diehl AM, et al.Methylprednisolone therapy in patients with severe alcoholic hepatitis. A randomized multicenter trial. Ann Intern Med. 1989;110(9):685–690. DOI: 10.7326/0003-4819-110-9-685.

Jophlin LL, Singal AK, Bataller R, et al.ACG Clinical Guideline: Alcohol-Associated Liver Disease. Am J Gastroenterol. 2024;119(1):30–54. DOI: 10.14309/ajg.0000000000002572.

American Association for the Study of Liver Diseases (AASLD).Why do we use steroids, Maddrey's Discriminant Function, and the Lille score in Alcohol-Associated Hepatitis? Official educational resource.

Clinical disclaimer: This calculator is intended for healthcare professionals as a clinical decision-support aid. It does not establish the diagnosis of alcohol-associated hepatitis and must not replace clinical assessment, specialist consultation, or current guideline-based management. Interpret the result in the context of the patient's complete clinical condition and laboratory findings.