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EPIC CODE: LAB6005 Nonalcoholic Steatohepatitis (NASH)-FibroTest, Serum and Plasma

Additional Codes

Sunquest:  NSFIBM
Mayo:         NSFIB
Previously: ARUP 2012521

Ordering Guidance

This test is not offered for patients younger than 14 years of age. Testing will be canceled if a specimen is received from a patient in this age group.

Necessary Information

Age and sex are required.

Specimen Required

Both serum and plasma are required for this test.


Patient Preparation: Fasting for at a minimum of 12 hours is required


Specimen Type: Serum

Supplies: Sarstedt 5 mL Aliquot Tube (Amber) (T915)

Collection Container/Tube:

Preferred: Serum gel

Acceptable: Red top

Submission Container/Tube: Amber vial

Specimen Volume: 4 mL

Collection Instructions:

1. Centrifuge and aliquot serum into an amber vial within 2 hours of collection.

2. Centrifuged serum must be light protected within 4 hours of collection. It is acceptable to draw the blood and then protect it from light after centrifugation as long as it's within 4 hours of collection.

3. Label specimen as serum.


Specimen Type: Plasma

Collection Container/Tube: Gray top (potassium oxalate/sodium fluoride)

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL

Collection Instructions:

1. Centrifuge and aliquot plasma into plastic vial.

2. Label specimen as plasma.


If not ordering electronically, complete, print, and send Gastroenterology and Hepatology Client Test Request (T728) with the specimen

Secondary ID


Useful For

Diagnosis and the follow-up of liver fibrosis, steatosis and inflammation


Estimating hepatic fibrosis


Assessing inflammation for metabolic diseases


Assessing severity of nonalcoholic steatohepatitis (NASH) in patients with nonalcoholic fatty liver disease with steatosis (NAFLD)


Assessing steatosis or fatty liver


Reassuring patients with steatosis only, without fibrosis


Managing patients with severe injuries such as advanced fibrosis and NASH

Profile Information

Test ID Reporting Name Available Separately Always Performed
INTNS NASH-FibroTest, Interpretation No Yes
APOAF Apolipoprotein A1, S No Yes
A2MF Alpha-2-Macroglobulin, S Yes, (Order A2M) Yes
HAPTF Haptoglobin, S Yes, (Order HAPT) Yes
ALTF Alanine Aminotransferase (ALT), S Yes, (Order ALT) Yes
GGTF Gamma Glutamyltransferase (GGT), S Yes, (Order GGT) Yes
TBILF Bilirubin, Total, S Yes, (Order BILIT) Yes
ASTF Aspartate Aminotransferase (AST), S Yes, (Order AST) Yes
CHOLF Cholesterol, Total, S Yes, (Order CHOL) Yes
TRIGF Triglycerides, S Yes, (Order TRIG) Yes
GLURF Glucose, Fasting, P No Yes

Testing Algorithm

This test is a patented test algorithm developed by BioPredictive. It combines 10 standard biomarkers: gamma-glutamyltransferase, total bilirubin, alpha-2-macroglobulin, apolipoprotein A1, haptoglobin, alanine aminotransferase, aspartate aminotransferase, total cholesterol, triglycerides, and fasting glucose. These markers are weighted depending on the patient's age and sex.


Testing is compliant with BioPredictive's technical recommendations and approvals.

Method Name

INTNS: Algorithm and interpretation provided through BioPredictive

APOAF: Automated Turbidimetric Immunoassay

A2MF, HAPTF: Nephelometry

ALTF: Photometric Rate, L-Alanine with Pyridoxal-5-Phosphate

GGTF: Photometric Rate

TBILF: Photometric, Diazonium Salt (DPD)

ASTF: Photometric Rate, L-Aspartate with Pyridoxyl-5-Phosphate

CHOLF, TRIGF: Enzymatic Colorimetric

GLURF: Photometric, Hexokinase

Reporting Name


Specimen Type

Plasma NaFl-KOx

Specimen Minimum Volume

Serum: 2 mL
Plasma: 0.25 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Plasma NaFl-KOx Refrigerated (preferred) 7 days
  Frozen  14 days
  Ambient  7 days
Serum Refrigerated (preferred) 7 days LIGHT PROTECTED
  Frozen  14 days LIGHT PROTECTED
  Ambient  24 hours LIGHT PROTECTED

Reject Due To

Gross hemolysis Reject
Gross lipemia Reject
Gross icterus Reject
Patients <14 years of age Reject

Clinical Information

This test estimates the 3 elementary features of metabolic liver disease: steatosis, activity, and fibrosis. The estimation is made by measuring 10 standard serum biomarkers (gamma-glutamyl transferase, total bilirubin, alpha-2-macroglobulin, apolipoprotein A1, haptoglobin, alanine aminotransferase, aspartate aminotransferase, cholesterol, triglycerides and fasting plasma glucose). Results from these tests are combined with the patient's age and sex to estimate hepatic fibrosis (FibroTest), steatosis (SteatoTest 2) and activity (NashTest 2) scores.

Reference Values


NashTest 2 score








mild NASH



moderate NASH



severe NASH

 *Boundary values can apply to 2 stages based on rounding. For example, a NashTest 2 score of 0.245 will round up to 0.25 and be staged N0. A NashTest 2 score of 0.254 will round down to 0.25 and be staged N2.



SteatoTest 2 score





no steatosis (<5%)



mild steatosis (5-33%)



moderate/severe steatosis (34-100%)

 *Boundary values can apply to 2 stages based on rounding. For example, a SteatoTest 2 score of 0.395 will round up to 0.40 and be staged S0. A SteatoTest 2 score of 0.404 will round down to 0.40 and be staged S1.



FibroTest score





No fibrosis



No fibrosis



Minimal fibrosis



Minimal fibrosis



Moderate fibrosis



Advanced fibrosis



Advanced fibrosis



Severe fibrosis (Cirrhosis)

 *Boundary values can apply to 2 stages based on rounding. For example, a FibroTest score of 0.305 will round up to 0.31 and be staged F1. A FibroTest score of 0.314 will round down to 0.31 and be staged F1-F2.



≤18 years: 178-495 mg/dL

>18 years: 100-280 mg/dL




<12 months: Not established

≥1 year: 7-55 U/L



<12 months: Not established

≥1 year: 7-45 U/L




<24 months: Not established

2-17 years

Low: <115 mg/dL

Borderline low: 115-120 mg/dL

Acceptable: >120 mg/dL

≥18 years: ≥120 mg/dL



<24 months: Not established

2-17 years

Low: <115 mg/dL

Borderline low: 115-120 mg/dL

Acceptable: >120 mg/dL

≥18 years: ≥140 mg/dL




0-11 months: <178 U/L

12 months-6 years: <21 U/L

7-12 years: <24 U/L

13-17 years: <43 U/L

≥18 years: 8-61 U/L



0-11 months: <178 U/L

12 months-6 years: <21 U/L

7-12 years: <24 U/L

13-17 years: <26 U/L

≥18 years: 5-36 U/L



30-200 mg/dL



0-6 days: Refer to for information on age-specific (postnatal hour of life) serum bilirubin values.

7-14 days: <15.0 mg/dL

15 days to 17 years: ≤1.0 mg/dL

≥18 years: ≤1.2 mg/dL




0-11 months: Not established

1-13 years: 8-60 U/L

≥14 years: 8-48 U/L



0-11 months: Not established

1-13 years: 8-50 U/L

≥14 years: 8-43 U/L



The National Lipid Association and the National Cholesterol Education Program (NCEP) have set the following guidelines for lipids in adults 18 years old and older:



Desirable: <200 mg/dL

Borderline High: 200-239 mg/dL

High: ≥240 mg/dL



Normal: <150 mg/dL

Borderline High: 150-199 mg/dL

High: 200-499 mg/dL

Very High: ≥500 mg/dL


The Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents has set the following guidelines for lipids in children 2 to 17 years of age:



Acceptable: <170 mg/dL

Borderline High: 170-199 mg/dL

High: ≥200 mg/dL



2-9 years

Acceptable: <75 mg/dL

Borderline High: 75-99 mg/dL

High: ≥100 mg/dL


10-17 years

Acceptable: <90 mg/dL

Borderline High: 90-129 mg/dL

High: ≥130 mg/dL

For SI unit Reference Values, see



0-11 months: Not established

≥1 year: 70-100 mg/dL


This test provides numeric scores that assess hepatic fibrosis (FibroTest), hepatic inflammation (NashTest 2), and steatosis (SteatoTest 2). Interpretation of the scores is provided in the report. Individual results from the 10 component tests are also provided with institution-specific reference intervals.


FibroTest is reported relative to a scale ranging from F0-F4 (F0=no fibrosis, F1=minimal fibrosis, F2=moderate fibrosis, F3=advanced fibrosis, F4=severe fibrosis [cirrhosis]). Fibrosis scores may overlap (eg, F0/F1, F1/F2).


NashTest 2 is reported relative to a scale ranging from N0-N3 (N0=no nonalcoholic steatohepatitis: NASH, N1=mild NASH, N2=moderate NASH, N3=severe NASH).


Steatosis is reported relative to a scale ranging from S0-S2S3 (S0=no steatosis [<5%], S1=mild steatosis [5-33%], S2/S3=moderate/severe steatosis [34-100%]). A stage of S1 or S2S3 is considered clinically significant.


The tests will be deferred for patients with acute hemolysis, acute hepatitis, acute inflammation, and extra hepatic cholestasis.


The advice of a specialist should be sought for interpretation in chronic hemolysis or Gilbert syndrome.


The test interpretation has not been validated for liver transplant patients.


Isolated extreme values of one of the components should lead to caution in interpreting the results.


In case of discordance between a biopsy result and a test, it is recommended to seek the advice of a specialist. The causes of these discordances could be due to a flaw of the test or to a flaw in the biopsy: ie, a liver biopsy has a 33% variability rate for one fibrosis stage.


NashTest 2 is set to N0 is the absence of steatosis based on the definition of nonalcoholic steatohepatitis (NASH). SteatoTest 2 scores of less than 0.40 (S0) will default NashTest 2 to N0.

Clinical Reference

1. BioPredictive: Technical Recommendations for FibroTest, FibroMax, and NASH-FibroTest assays, Bio Predictive. Version 3.0

2. Poynard T, Peta V, Munteanu M, et al: The diagnostic performance of a simplified blood test (SteatoTest-2) for the prediction of liver steatosis. Eur J Gastroenterol and Hepatol. 2019 Mar;31(3)393-402. doi: 10.1097/MEG.0000000000001304

3. Munteanu M, Pais R, Peta V, et al: Long-term prognostic value of the FibroTest in patients with non-alcoholic fatty liver disease, compared to chronic hepatitis C, B, and alcoholic liver disease. Aliment Pharmacol Ther. 2018 Nov:48(10):1117-1127. doi: 10.1111/apt.14990

4. Poynard T, Munteanu M, Charlotte F, et al: Diagnostic performance of a new noninvasive test for nonalcoholic steatohepatitis using a simplified histological reference. Eur J Gastroenterol and Hepatol. 2018 May;30(5):569-577. doi: 10.1097/MEG.0000000000001064

5. Poynard T, Munteanu M, Charlotte F, et al: Impact of steatosis and inflammation definitions on the performance of NASH tests. Eur J Gastroenterol Hepatol. 2018 Apr;30(4):384-391. doi: 10.1097/MEG.0000000000001033

6. Munteanu M, Tiniakos D, Anstee Q, et al: Diagnostic performance of FibroTest, SteatoTest and ActiTest in patients with NAFLD using the SAF score as histological reference. Aliment Pharmacol Ther. 2016 Oct;44(8):877-889. doi: 10.1111/apt.13770

7. Vilar-Gomez E, Chalasani N: Non-invasive assessment of non-alcoholic fatty liver disease: Clinical prediction rules and blood-based biomarkers. J Hepatol. 2018 Feb;68(2):305-315. doi: 10.1016/j.jhep.2017.11.013

8. Ratziu V, Charlotte F, Heurtier A, et al: Sampling variability of liver biopsy in nonalcoholic liver disease. Gastroenterology. 2005 Jun;128(7):1898-1906. doi: 10.1053/j.gastro.2005.03.084

Method Description

NASH-FibroTest Interpretation:

Proprietary algorithm owned by BioPredictive


Alpha-2-Macroglobulin and Haptoglobin:

In this method, the light scattered onto the antigen-antibody complexes is measured. The intensity of the measured scattered light is proportional to the amount of antigen-antibody complexes in the sample under certain conditions. If the antibody volume is kept constant, the signal behaves proportionally to the antigen volume.


A reference curve is generated by a standard with a known antigen content on which the scattered light signals of the samples can be evaluated and calculated as an antigen concentration. Antigen-antibody complexes are formed when a sample containing antigen and the corresponding antiserum are put into a cuvette. A light beam is generated with a light-emitting diode, which is transmitted through the cuvette. The light is scattered onto the immuno-complexes that are present. Antigen and antibody are mixed in the initial measurement, but no complex is formed yet. An antigen-antibody complex is formed in the final measurement.


The result is calculated by subtracting value of the final measurement from the initial measurement. The distribution of intensity of the scattered light depends on the ratio of the particle size of the antigen-antibody complexes to the radiated wavelength.(Unpublished Mayo method; instruction manual: Siemens Nephelometer II, Siemens, Inc; Version 2.3. 2008; Addendum to the Instruction Manual 2.3, 08/2017)


Alanine Aminotransferase:

Alanine aminotransferase (ALT) activity is determined by a kinetic method using a coupled enzyme reaction where the rate of reduced nicotinamide adenine dinucleotide (NADH) consumption is measured at 340 nm. The NADH decrease is directly proportional to the ALT activity.(Package insert: ALT reagent. Roche Diagnostics; 2018)


Apolipoprotein A1:

Anti-apolipoprotein A-1 antibodies react with the antigen in the sample to form antigen/antibody complexes which, following agglutination, can be measured turbidimetrically.(Package insert: Tina-quant Apolipoprotein A-1. Roche Diagnostics; 2019)



This is an enzyme colorimetric method (rate method) where gamma-glutamyltransferase (GGT) transfers the gamma-glutamyl group of the substrate (L-gamma-glutamyl-3-carboxy-4-nitroanilide) to glycylglycine. The amount of 5-amino-2-nitrobenzoate liberated is proportional to the GGT activity and can be determined photometrically.(Package insert: GGT2 reagent. Roche Diagnostics; V10, 01/2017)


Bilirubin, Total:

Total bilirubin, in the presence of a suitable solubilizing agent, is coupled with 3,5-dichlorophenyl diazonium in a strongly acidic medium. The color intensity of the red azo dye formed is directly proportional to the total bilirubin and can be determined photometrically.(Package insert: Bilirubin Total Gen. 3. Roche Diagnostics; 2019)


Aspartate Aminotransferase:

Aspartate aminotransferase (AST) is measured by a coupled enzyme kinetic method where the rate of decrease of NADH, determined at 340 nm, is directly proportional to the AST activity.(Package insert: AST reagent. Roche Diagnostics; 2019)


Cholesterol, Total:

Cholesterol is measured by an automated enzymatic method. The reagents include cholesterol ester hydrolase, cholesterol oxidase, and a coupled colorimetric end-point chemistry system.(Package insert: Cholesterol Reagent. Roche Diagnostics; 2018)



This test uses a lipoprotein lipase from microorganisms for the rapid and complete hydrolysis of triglycerides to glycerol followed by oxidation to dihydroxyacetone phosphate and hydrogen peroxide. The hydrogen peroxide produced then reacts with 4-aminophenazone and 4-chlorophenol under the catalytic action of peroxidase to form a red dyestuff (Trinder endpoint reaction). The color intensity of the red dyestuff formed is directly proportional to the triglyceride concentration and can be measured photometrically.(Package insert: Triglyceride Reagent. Roche Diagnostics; 01/2020)



Glucose in the serum, in the presence of hexokinase, is converted to glucose-6-phosphate (G-6-P). Glucose-6-phosphate dehydrogenase (G-6-PDH) oxidizes G-6-P in the presence of nicotinamide adenine dinucleotide phosphate (NADP[+]) to gluconate-6-phosphate and NADPH. The rate of NADPH formation is directly proportional to glucose concentration in the serum and is measured photometrically.(Package insert: Glucose Reagent. Roche Diagnostics; 2019)

Day(s) Performed

Monday through Friday

Report Available

2 to 4 days

Specimen Retention Time

7 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information


LOINC Code Information

Test ID Test Order Name Order LOINC Value
NSFIB NASH-FibroTest 93691-4


Result ID Test Result Name Result LOINC Value
TBILF Bilirubin, Total, S 1975-2
ALTF Alanine Aminotransferase (ALT), S 1743-4
A2MF Alpha-2-Macroglobulin, S 1835-8
APOAF Apolipoprotein A1, S 1869-7
GGTF Gamma Glutamyltransferase (GGT), S 2324-2
HAPTF Haptoglobin, S 46127-7
GLURF Glucose, Fasting, P 1558-6
TRIGF Triglycerides, S 2571-8
CHOLF Cholesterol, Total, S 2093-3
ASTF Aspartate Aminotransferase (AST), S 30239-8
SCRF FibroTest Score 48795-9
STGF FibroTest Stage 48794-2
INTEF FibroTest Interpretation 88447-8
SCRN2 NashTest 2 Score 93692-2
GRDN NashTest 2 Grade 93693-0
INTEN NashTest 2 Interpretation 93694-8
SCRS2 SteatoTest 2 Score 93695-5
GRDS SteatoTest 2 Grade 93696-3
INTEI SteatoTest 2 Interpretation 93697-1
CMMS NASH-FibroTest Comment 48767-8
NUM BioPredictive Serial Number 74715-4

NY State Approved