Nafld Fibrosis Score Calculator - Liver Fibrosis Triage by Angulo 2007

A nafld fibrosis score calculator turns six routine clinical inputs - age, BMI, IFG or diabetes status, AST/ALT ratio, platelet count, and serum albumin - into the Angulo 2007 fibrosis index used to triage advanced liver fibrosis in adults with non-alcoholic fatty liver disease.

• • NAFLD follow-up: screen adults with non-alcoholic fatty liver disease for advanced fibrosis between specialist visits.
• • Primary care triage: flag patients whose routine labs suggest they need elastography or a hepatology referral.
• • Pre-treatment baseline: record a numeric fibrosis baseline before starting therapy that may affect liver health.
• • Resource-limited screening: support population-level fibrosis screening in clinics where transient elastography or liver biopsy is not readily available.

The score runs on inputs that are already on most standard liver and metabolic panels, which is why it is one of the most widely cited non-invasive fibrosis scores in the NAFLD literature. A value below -1.455 points to low probability, a value above 0.676 points to high probability, and the band in between needs elastography or biopsy.

The score is a screening tool, not a stand-alone diagnosis. The Angulo 2007 paper still calls for elastography or liver biopsy before any treatment escalation.

When a clinic needs a second blood-based liver fibrosis screen that uses only AST, the AST upper limit, and platelets, the Apri Calculator applies the WHO 2015 cut-offs.

The calculator applies the Angulo 2007 multivariable equation and returns a two-decimal fibrosis index along with BMI, the AST/ALT ratio, and a label against the -1.455 and 0.676 cutoffs.

• age: patient age in years at the time of the blood draw.
• BMI: body mass index in kg/m^2, computed from height and weight.
• IFG or diabetes: 1 if impaired fasting glucose or known diabetes is present, otherwise 0.
• AST/ALT and labs: AST divided by ALT, plus platelet count in 10^9 per L and serum albumin in g/dL.

The calculator rounds the result to two decimal places to match the original publication. A value of -1.455 is Indeterminate and a value of 0.676 is Indeterminate as well, which keeps the published high cutoff as a positive screen.

According to Angulo et al., Hepatology 2007, the NAFLD fibrosis score is -1.675 plus 0.037 times age plus 0.094 times BMI plus 1.13 if IFG or diabetes is present plus 0.99 times the AST/ALT ratio minus 0.013 times platelet count minus 0.66 times albumin, with cutoffs of -1.455 and 0.676.

For teams that prefer to read the AST/ALT ratio against the De Ritis bands before plugging it into the Angulo model, the AST ALT Ratio Calculator keeps the same AST and ALT inputs.

Four concepts drive the score. Naming them keeps the index from being read as a black box.

The combination of high AST/ALT ratio, low platelets, low albumin, older age, and high BMI is what makes the model perform well, which is why the calculator keeps all six inputs editable.

When a clinician wants the body mass index broken out as a standalone result, the BMI Calculator takes the same height and weight inputs and returns a WHO classification band.

The form runs on six numbers from standard liver, metabolic, and hematology panels, plus a height and weight pair for body mass index.

1. 1 Enter age and IFG or diabetes status: type the patient age in years (18-100) and select Yes or No for impaired fasting glucose or known diabetes.
2. 2 Enter height and weight: type the patient height in centimeters and weight in kilograms. The calculator computes BMI from those two fields automatically.
3. 3 Enter AST and ALT: type the AST and ALT values in U/L from the most recent liver function panel. The calculator refreshes the AST/ALT ratio as you type.
4. 4 Enter platelets and albumin: type the platelet count in 10^9 per L and the serum albumin in g/dL from the most recent complete blood count and metabolic panel.
5. 5 Read the score and the band: check the rounded NAFLD fibrosis score and the Fibrosis Band label. Scores below -1.455 are low probability, scores above 0.676 are high probability, and the rest is indeterminate.

A 55-year-old with NAFLD, BMI 29.4, IFG, AST 45 U/L, ALT 50 U/L, platelets 180 x 10^9 per L, and albumin 4.2 g/dL reads a NAFLD fibrosis score of 0.03 in the indeterminate band, which means elastography or a hepatology referral is the next step.

When a clinic reviews kidney and liver function on the same visit, the GFR Calculator applies the CKD-EPI equation to serum creatinine, age, and sex.

Using the calculator alongside routine liver and metabolic panels has concrete advantages for clinicians, dietitians, and patients tracking fatty liver disease.

• • Built on routine clinical inputs: the only required values are age, height, weight, IFG or diabetes status, AST, ALT, platelets, and albumin, which are already on most standard liver and metabolic panels.
• • Auto-computed body mass index: the calculator computes BMI from height and weight so the user does not need to convert units.
• • Live AST/ALT ratio: the AST/ALT ratio updates as the user types, so any change in either liver enzyme refreshes the fibrosis score and the label instantly.
• • Angulo 2007 cutoffs built in: the -1.455 and 0.676 cutoffs from the original 2007 paper are applied automatically.
• • Pairs with peer liver scores: the same AST, ALT, and platelet values feed the APRI and AST/ALT ratio calculators, so the score can be read next to other non-invasive fibrosis screens.

The score is a planning tool, not a treatment recommendation. The Angulo 2007 paper is explicit that the index is for screening and triage, and that elastography or liver biopsy remains the next step when the result will change care.

When the same lab workup also includes a urine albumin-to-creatinine ratio, the ACR Calculator applies the same six-input style to screen for diabetic kidney disease.

Four factors move the score the most, and three limitations matter when the result is read against a treatment plan.

• • The intermediate band is the score's biggest limitation. The Angulo 2007 cohort placed about a third of patients in the -1.455 to 0.676 range, and any result in that band still needs elastography or liver biopsy before care changes.
• • The score is calibrated for adults with non-alcoholic fatty liver disease, not alcohol-related liver disease or viral hepatitis. Acute illness, alcohol, and certain medications can move lab values without changing the true fibrosis stage, so a transiently high score should be re-checked after recovery.

External validation has confirmed the cutoffs. A 2013 World Journal of Gastroenterology study of 302 NAFLD patients found the -1.455 and 0.676 cutoffs predicted liver-related mortality and complications.

According to Marjot et al., Endocrine Reviews 2020, non-invasive scores such as the NAFLD fibrosis score are recommended as first-line triage for advanced fibrosis in adults with non-alcoholic fatty liver disease, with elastography or liver biopsy reserved for indeterminate results.

For a second liver-panel screen that uses the same serum albumin alongside total protein, the Albumin Globulin Ratio Calculator returns an A/G ratio with a low, normal, or high band that complements the Angulo index's serum albumin term.