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Ketone Body Ratio Calculator
The Ketone Body Ratio (ratio of β-Hydroxybutyrate to Acetoacetate) reflects the mitochondrial redox state (NADH/NAD+ ratio) of the liver.
In healthy individuals, this ratio is approximately 1:1. In Diabetic Ketoacidosis (DKA), the ratio typically rises to 3:1 or higher. In Alcoholic Ketoacidosis (AKA), the high NADH state can drive this ratio significantly higher (often > 10:1), leading to a paradoxically negative nitroprusside urine test (which only detects acetoacetate).
Ketone Levels
InputsResult
Normal Ratio: ~ 1 : 1
Clinical Context
Formula:
Ratio = β-Hydroxybutyrate (mmol/L) / Acetoacetate (mmol/L)
Clinical Significance:
• DKA (Diabetic Ketoacidosis): Ratio typically rises to between 3:1 and 10:1.
• AKA (Alcoholic Ketoacidosis): Ratio is often very high (>10:1) due to massive NADH production from alcohol metabolism. This shifts AcAc to β-HB.
• Nitroprusside Test (Dipstick): Only detects Acetoacetate. A high ratio (lots of β-HB, little AcAc) can cause a “false negative” or weakly positive dipstick despite severe ketoacidosis.
Recovery Phase: As ketoacidosis is treated, NADH levels fall, and β-HB oxidizes back to AcAc. This lowers the ratio but increases the AcAc concentration, causing the dipstick test to become more positive even as the patient improves.
Clinical References
How to Use This Calculator
Follow these steps to calculate the ketone ratio.
Input β-Hydroxybutyrate
Enter the serum beta-hydroxybutyrate level. You can use mmol/L (standard) or mg/dL.
Input Acetoacetate
Enter the serum acetoacetate level. Note: This is rarely measured directly in routine panels but is necessary for this ratio.
Interpret Result
The ratio will be displayed. A very high ratio (>10) suggests Alcoholic Ketoacidosis or prolonged starvation.
Frequently Asked Questions
Acetoacetate is unstable and decarboxylates to acetone spontaneously. Most labs rely on the nitroprusside reaction (dipstick) which is semi-quantitative, or they measure β-HB which is stable.
No. Urine ketones are semi-quantitative (1+, 2+, etc.) and primarily detect acetoacetate. This calculator requires quantitative serum levels.