What is Maddrey's Discriminant Function?

Maddrey's Discriminant Function (MDF) is a prognostic scoring tool for alcoholic hepatitis, calculated as 4.6 × (patient PT − control PT) + total bilirubin in mg/dL. A score ≥ 32 indicates severe disease with significantly elevated short-term mortality.

What does an MDF score of 32 or higher mean?

An MDF score ≥ 32 is the traditional threshold for severe alcoholic hepatitis. These patients have a 30-day mortality of 35–50% without treatment. Guidelines recommend considering a course of corticosteroids (prednisolone 40 mg/day for 28 days) if there are no contraindications such as active infection, GI bleeding, or renal failure.

Should I use INR or PT prolongation in the formula?

The original Maddrey formula uses PT prolongation (patient PT minus control PT) in seconds, not the INR. Using INR can overestimate or underestimate the score depending on the reagent used. This calculator uses PT in seconds as per the original validated formula.

What are the contraindications to steroids in alcoholic hepatitis?

Major contraindications include active bacterial or fungal infection, active gastrointestinal bleeding, uncontrolled diabetes, renal failure (creatinine > 2.5 mg/dL in some protocols), pancreatitis, and hepatitis B co-infection. Always assess for infection before starting steroids.

How does MDF compare to the MELD score for alcoholic hepatitis?

Both MDF and MELD predict short-term mortality in alcoholic hepatitis. MDF ≥ 32 is the classic threshold for steroid consideration. MELD > 20 is used as a supplementary marker. The Lille score (calculated after 7 days of steroids) is then used to assess steroid response and guide continuation.

Is this calculator a substitute for clinical judgment?

No. This tool is for educational and reference purposes only. Clinical decisions regarding steroid therapy, transplant listing, or other interventions must be made by a qualified hepatologist or gastroenterologist considering the full clinical picture.

Maddrey's Discriminant Function Calculator

Enter PT prolongation and serum bilirubin to calculate the Maddrey Discriminant Function score and get a steroid therapy recommendation.

Lab Values

Enter the patient's coagulation and liver function results.

Patient Prothrombin Time (PT) seconds

Control (Reference) PT seconds — typical 11–13 s

Total Serum Bilirubin mg/dL

If your lab reports bilirubin in µmol/L, divide by 17.1 to convert to mg/dL.

MDF Result

Enter lab values and click Calculate

MDF Score Reference

MDF Score	Severity	30-Day Mortality	Steroid Consideration
< 32	Non-severe	< 15%	Steroids generally not indicated; supportive care
32 – 54	Severe	35–45%	Steroids recommended if no contraindications (prednisolone 40 mg/day × 28 days)
≥ 55	Very severe	> 50%	Steroids recommended; evaluate for early liver transplant referral

Steroid contraindications include active infection, GI bleeding, uncontrolled diabetes, renal failure, and hepatitis B co-infection. Use the Lille score after 7 days to assess steroid response. For educational use only — clinical decisions require qualified medical evaluation.

Summary

Maddrey's Discriminant Function (MDF) is a validated clinical scoring system for alcoholic hepatitis, originally described by Maddrey et al. in 1978. The formula is MDF = 4.6 × (patient PT − control PT) + serum bilirubin (mg/dL). A score of 32 or higher identifies patients with severe disease who have a 30-day mortality exceeding 35% and who may benefit from corticosteroid therapy with prednisolone or methylprednisolone, provided there are no contraindications.

How it works

Enter the patient's prothrombin time (PT) in seconds.
Enter the control (laboratory reference) PT in seconds.
Enter the total serum bilirubin in mg/dL.
Click Calculate to compute the MDF score using the formula: MDF = 4.6 × (patient PT − control PT) + bilirubin.
Review the score, severity classification, and steroid therapy guidance.
Use the reference table below to understand score thresholds and clinical implications.

Use cases

Stratifying severity of alcoholic hepatitis at admission.
Identifying patients who may benefit from corticosteroid therapy.
Guiding clinical decision-making in hepatology and gastroenterology.
Monitoring disease progression with serial lab values.
Medical education and hepatology board exam preparation.
Comparing MDF with other alcoholic hepatitis scores such as MELD and Lille.
Quick bedside reference for hospitalist physicians managing alcoholic hepatitis.

Frequently Asked Questions

Last updated: 2026-05-23 · Reviewed by Nham Vu