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Alpha-1-Antitrypsin Unit Converter

Alpha-1-Antitrypsin (A1AT), also known as alpha-1-proteinase inhibitor, is a serine protease inhibitor (serpin) primarily synthesized in the liver. Its most critical physiological role is the inhibition of neutrophil elastase, an enzyme released by white blood cells to fight infection but which can damage lung tissue if left unchecked.

A1AT is a positive acute-phase reactant, meaning levels rise significantly during inflammation, infection, or tissue injury. Conversely, low levels are the hallmark of Alpha-1-Antitrypsin Deficiency, a genetic disorder predisposing individuals to early-onset pulmonary emphysema (due to unchecked elastase activity) and liver cirrhosis (due to accumulation of misfolded protein in hepatocytes). Accurate unit conversion is essential for comparing results across different laboratories and guidelines.

SI Units

Recommended

Grams per liter (Clinical SI) or Micromoles per liter.

Conventional Units

Clinical Context

A1AT levels are heavily influenced by the individual’s genotype (Pi type). The normal PiMM phenotype typically presents with serum levels of 90 – 200 mg/dL (0.9 – 2.0 g/L). Individuals with the PiZZ phenotype often have levels below 15% of normal (< 30 mg/dL), placing them at high risk for emphysema.

Because A1AT is an acute-phase protein, inflammation can falsely elevate levels into the “normal” range in deficient individuals. Therefore, quantitative testing should often be accompanied by genotyping or phenotyping if deficiency is suspected. The molar conversion is based on a molecular weight of ~52 kDa: 1 g/L ≈ 19.2 µmol/L.

Clinical References

How to Use This Calculator

Follow these steps to get accurate clinical conversions instantly.

1

Enter Values

Input your laboratory results into the corresponding unit field (e.g., mg/dL). You can use either dot or comma decimals.

2

Automatic Conversion

The calculator works in real-time. As you type in one field, all other units (like g/L or µmol/L) are instantly updated.

3

Verify Units

Check the SI Units section. g/L is the most common standard, but molar units are provided for research precision.

4

Reset

Use the Clear button to reset all fields before starting a new calculation.

? Frequently Asked Questions & Tips
Why do reference ranges vary?

Ranges depend on the method (nephelometry vs. immunoturbidimetry) and the specific phenotype of the population tested.

Is this test for genetics?

No, this converts the quantity of protein. Genetic testing (genotyping) is a separate molecular test.

Disclaimer: This calculator is provided for educational and reference purposes only. It is not intended for clinical diagnosis, treatment, or medical decision-making. Always consult a qualified healthcare professional and refer to your laboratory’s official reference ranges before interpretation.