IGF-I - serum

Last updated: Wednesday, 17, March, 2004
Item Process
Specimen

5 mL blood in a plain tube.

Method

Immunoassay.

Reference Interval

Varies with age, gender and pubertal status.

Adult: 13-50 nmol/L.

Application

Diagnosis of acromegaly or gigantism.

Diagnosis of Laron dwarfism.

Limited value in the assessment of growth hormone deficiency or nutritional status.

Interpretation

Levels are increased in acromegaly, and the test is used in the initial assessment of patients, prior to a growth hormone suppression test.

Its diagnostic value is limited at the time of puberty, during malnutrition and with severe illness.

In Laron dwarfism growth hormone is not reduced but IGF-I is reduced.

Low IGF-I has been used as a test for protein malnutrition but interpretation is difficult in view of changes in plasma IGF-binding proteins.

Reference

Brabant G. Eur J Endocrinol 2003; 148:2: 15-20.