Simplified Autoimmune Hepatitis (AIH) Score

Simplified AIH Score Calculator

ANA or SMA

IgG Level

Liver Histology

Absence of Viral Hepatitis

Simplified AIH Score: –

Awaiting input

Select all criteria to compute the score.

Diagnoses autoimmune hepatitis.

Why Use

AIH is multifactorial, complex, and typically has many competing diagnoses. The score offers a data driven, consensus-based path to help guide treatment and is likely to be better than clinical judgment alone.

When to Use

Patients with established hepatitis and available liver biopsy results, but unclear diagnosis.

Formula

Addition of the selected points: Variable 0 points 1 point 2 points ANA or SMA/F-actin Negative Positive or strongly positive* -- LKM1 <1:40 -- ≥1:40* SLA Negative -- Positive* IgG Normal >Upper limit of normal >1.1× upper limit of normal Liver histology** -- Compatible with AIH Typical of AIH Viral hepatitis Present -- Absent *Maximum 2 points total (e.g. if ANA or SMA/F-actin is positive or strongly positive, LKM1 ≥1:40, and SLA is positive, only 2 points are assigned, not 5). **If histology is normal, AIH is not the diagnosis. AIH, autoimmune hepatitis; ANA, antinuclear antibody; LKM1, Liver Kidney Microsome type 1; SLA, soluble liver antigen; SMA, smooth muscle antibody; IgG, immunoglobulin G.

Pearls / Pitfalls

The Simplified Autoimmune Hepatitis (AIH) Score was developed to simplify AIH diagnosis and reduce false positive diagnoses.

Management

We are unaware of validated management algorithms using the AIH scores.

Critical Actions

Overlap with multiple hepatic conditions is always a concern to consider despite score findings, and ‘likely’ scores are more predictive than ‘probable’ ones.

Advice

AIH is a complex diagnosis partly because there is no anatomic criterion (i.e. ‘gold’) standard. AIH scoring neatly solves this problem by defining the diagnosis. ‘Likely’ scores appear highly reliable.

More Information

Interpretation: Simplified AIH Score Diagnosis ≤5 Possible AIH (though further testing should be done) 6 Probable AIH ≥7 Definite AIH