Hepatic Steatosis Index (HSI) Calculator

Hepatic Steatosis Index (HSI) Calculator for Endocrinology. Below 30 and above 36 are the original lower and upper screening bands. Values from 30 through 36 are intermediate. A band is not an individual disease probability, and neither reassuring enzymes nor a lower index establish absence of clinically important liver disease.

For shared guidance on choosing a tool and documenting results, read the clinical calculator workflow.

How this calculator works

HSI = 8 x ALT/AST + BMI, with 2 added for female sex and 2 for diabetes. Both enzyme entries must be positive; AST is the denominator. The output retains full precision for classification and rounds only the displayed number.

When to use this calculator

Use to understand a historical, noninvasive steatosis screening approach. The original Korean health-check study did not establish a universal diagnosis from this number. Confirm the clinical question before using a steatosis index when the actual concern is fibrosis or another liver disease.

Inputs used

  • ALT and AST in U/L from the same assessment
  • BMI in kg/m2
  • Sex convention and established diabetes status

Clinical interpretation

Below 30 and above 36 are the original lower and upper screening bands. Values from 30 through 36 are intermediate. A band is not an individual disease probability, and neither reassuring enzymes nor a lower index establish absence of clinically important liver disease.

Worked example

ALT 40, AST 20, BMI 28, female sex and diabetes give 8 x 2 + 28 + 2 + 2 = 48.000. With ALT = AST, no additions and BMI 22, HSI is exactly 30; BMI 28 gives exactly 36. Both boundary values are intermediate.

Limitations and safety notes

HSI does not determine alcohol exposure, MASH, fibrosis or a treatment indication. The historical NAFLD study population is not automatically interchangeable with every current MASLD population. Software input limits are not evidence of performance at extreme values.

Frequently asked questions

Does a high HSI mean cirrhosis?

No. The index concerns steatosis screening, not fibrosis stage.

Why does 36 remain intermediate?

The original upper cutoff was greater than 36, not greater than or equal to 36.

References

  • Original Lee HSI abstract: equation, Korean screening population and strict <30/>36 cutoffs. https://pubmed.ncbi.nlm.nih.gov/19766548/

Editorial review and citation methodology

Maintained by the Quick Medical Calculator Editorial Team. Content record date: September 9, 2026. A content date is not evidence of independent clinical review. Individual clinical sign-off is not recorded on this page.

  • Prefer original validation studies for scoring systems and prediction tools.
  • Use current specialty society guidance, transplant allocation policy, public health guidance, or regulator resources when they govern clinical use.
  • Include limitations and safety notes when a calculator is population-specific, context-dependent, or unsuitable as a standalone decision tool.

Related reviewed calculators