Maddrey Discriminant Function Calculator

Calculate the Maddrey Discriminant Function (MDF) for alcoholic-hepatitis severity context and compare it with related liver-severity markers such as MELD.

About the Maddrey Discriminant Function Calculator

The Maddrey Discriminant Function (MDF) is a long-used bedside severity score for suspected alcoholic hepatitis. It combines prothrombin-time prolongation and total bilirubin into a single number that helps place a case below or above the classic severe-range threshold described in the literature.

This page is best used as an educational severity worksheet, not as a management pathway. MDF is usually interpreted alongside MELD, encephalopathy, renal function, infection status, and laboratory trends rather than on its own. The calculator keeps those related markers together so the score can be read in broader liver-injury context.

Why Use This Maddrey Discriminant Function Calculator?

The discriminant function is useful when you want to place PT prolongation and bilirubin into a familiar severe-versus-non-severe framework. This page keeps MDF, MELD, and Lille timing context together so the result stays anchored to the rest of the severity picture.

How to Use This Calculator

  1. Enter the patient's prothrombin time (PT) in seconds.
  2. Enter the laboratory's control PT value.
  3. Enter total bilirubin, creatinine, albumin, and INR.
  4. Enter the patient's age and hepatic encephalopathy status.
  5. Review the MDF score, MELD context, and severe-range framing.
  6. Remember that a full Lille score needs day-7 bilirubin and is not calculated here.

Formula

Maddrey Discriminant Function (MDF): MDF = 4.6 × (Patient PT − Control PT) + Total Bilirubin (mg/dL) Threshold: MDF ≥ 32 = Classic severe-range cutoff in alcoholic-hepatitis literature MELD = 3.78 × ln(Bilirubin) + 11.2 × ln(INR) + 9.57 × ln(Creatinine) + 6.43 Lille Score (day 7): Uses day-0 and day-7 bilirubin, age, albumin, creatinine, and PT. It is mainly a follow-up response score and is not fully calculated on this page.

Example Calculation

Result: MDF = 4.6 × (22−12) + 12 = 58.0 — Above the classic severe-range cutoff

MDF 58.0 exceeds the ≥32 threshold, placing the case in the severe range described in the original MDF framework. It should still be interpreted with MELD, renal function, encephalopathy, and the rest of the liver-injury picture rather than as a stand-alone conclusion.

Tips & Best Practices

What MDF Measures

Alcoholic hepatitis can involve jaundice, impaired hepatic synthetic function, renal dysfunction, encephalopathy, and other complications. MDF focuses on only two pieces of that picture: bilirubin and prothrombin-time prolongation. That narrow scope is useful for a quick severity summary, but it also explains why MDF can never describe the whole case by itself.

Why MDF Is Still Used

MDF remains one of the quickest ways to summarize bilirubin elevation and coagulopathy in a single number. Even though other scores such as MELD are also widely used, MDF still gives a familiar severe-versus-non-severe anchor for educational discussion and historical comparison.

Limits of the Worksheet

This page keeps MELD and Lille timing context visible so the MDF result is not read in isolation. Even so, it is still only a simplified worksheet. Real interpretation depends on trends over time, complications, and direct clinical assessment rather than on one score alone.

Sources & Methodology

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Methodology

This worksheet applies the classic Maddrey discriminant function and related liver-risk comparisons to summarize alcoholic hepatitis severity context. It is a comparison aid, not a treatment order or diagnosis on its own.

Sources

Frequently Asked Questions

What is the Maddrey Discriminant Function?

The MDF is a bedside severity score developed in 1978 for suspected alcoholic hepatitis. It weights prothrombin-time prolongation and bilirubin into a single number that helps separate lower-severity presentations from the severe range commonly discussed in hepatology practice.

What does an MDF ≥ 32 mean?

MDF ≥ 32 is the classic cutoff used to flag the severe range in alcoholic-hepatitis literature. It is a severity marker, not a stand-alone pathway, so the result still needs broader clinical interpretation.

What is the Lille score?

The Lille score is a day-7 follow-up score that uses the bilirubin trend along with age, albumin, creatinine, and PT. Because it depends on day-7 data, this page only notes its role and does not calculate it fully.

Why show MELD alongside MDF?

MDF and MELD describe overlapping but different parts of the same liver-injury picture. Reviewing both helps frame whether a result looks consistently severe or whether other context needs closer review.

Does this page tell me what treatment should be used?

No. This page is an educational severity worksheet. It does not determine medication use, ICU care, transplant eligibility, or any other treatment decision.

Why is the mortality estimate only approximate?

The short-term mortality context comes from older cohorts and broad severity categories. It should be read as background information rather than as an individualized prediction.

Can MDF replace specialist liver assessment?

No. MDF is only one score. Alcoholic-hepatitis assessment still depends on the broader clinical picture, laboratory trends, complications, and direct clinical review.

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