Albumin/globulin ratio (A/G ratio)

What it measures

Compares albumin with globulin levels. Changes in the ratio help point toward liver disease, kidney protein loss or excess immunoglobulin production.

Specimen and preparation

• Specimen: Serum
• Tube: Gold top

Reference range

Reference ranges differ between laboratories, methods and populations. Always use the range printed on your own lab report.

Causes of high values

• Antibody deficiency (low globulin)
• Dehydration (mild effect)

Causes of low values

• Multiple myeloma and other paraproteinemias
• Liver cirrhosis
• Nephrotic syndrome
• Chronic inflammation or autoimmune disease

Method

Calculated: albumin ÷ (total protein − albumin)

Good to know

An inverted ratio (below 1.0) is a common trigger for protein electrophoresis.

Related tests