Test Description

Insulin-like growth factor (IGF)-I (also known as somatomedin C and somatomedin A) and IGF-II (multiplication stimulating activity or MSA) belong to the family of insulin-like growth factors that are structurally homologous to proinsulin. Mature IGF-I and IGF-II share approximately 70% sequence identity. Both IGF-I and IGF-II are expressed in many tissues and cell types and may have autocrine, paracrine and endocrine functions. Mature IGF-I and IGF-II are highly conserved between the human, bovine and porcine proteins (100% identity), and exhibit cross-species activity.

When should this test be ordered?
A test for insulin-like growth factor-1 (IGF-1) may be used to help identify growth hormone (GH) deficiency; it is not diagnostic of a GH deficiency but may be ordered along with GH stimulation tests to offer additional information. Further, it can be used as follow-up to abnormal results on other hormone tests and to evaluate pituitary function.
High Risk · High Risk
Out of reference range.
Borderline Risk · None
Not determined for this test.
Low Risk · Low Risk Reference range
Male:
(0-1459) days : 0 - 189 (ng/ml)
(1460-2554) days: 47-231 (ng/mL)
(2555-3649) days: 55-222 (ng/mL)
(3650-4379) days: 95-315 (ng/mL)
(4380-5109) days: 95-460 (ng/mL)
(5110-5839) days: 211-512 (ng/mL)
(5840-6934) days: 57-426 (ng/mL)
(6935-8029) days: 105-346 (ng/mL)
(8030-9124) days: 107-367 (ng/mL)
(9125-10949) days: 88-537 (ng/mL)
(10950-12274) days: 41-246 (ng/mL)
(12275- 14599) days: 57-241 (ng/mL)
(14600- 16424) days: 43-209 (ng/mL)
(16425-18249) days: 74-196 (ng/mL)
(18250- 20074) days: 55-248 (ng/mL)
(20075- 21899) days: 36-200 (ng/mL)
(21900-23724) days: 51-187 (ng/mL)
(23725- 25549) days: 37-219 (ng/mL)
(25550-29199) days: 0-200 (ng/mL)
(>= 29200) days: 0-323 (ng/mL)

Female:
(0-1459) days : 0 - 272 (ng/ml)
(1460-2554) days: 55-248 (ng/mL)
(2555-3649) days: 80-233 (ng/mL)
(3650-4379) days: 96-545 (ng/mL)
(4380-5109) days: 147-549 (ng/mL)
(5110-5839) days: 208-444 (ng/mL)
(5840-6934) days: 176-429 (ng/mL)
(6935-8029) days: 105-346 (ng/mL)
(8030-9124) days: 107-367 (ng/mL)
(9125-10949) days: 88-537 (ng/mL)
(10950-12274) days: 41-246 (ng/mL)
(12275- 14599) days: 57-241 (ng/mL)
(14600- 16424) days: 43-209 (ng/mL)
(16425-18249) days: 74-196 (ng/mL)
(18250- 20074) days: 55-248 (ng/mL)
(20075- 21899) days: 36-200 (ng/mL)
(21900-23724) days: 51-187 (ng/mL)
(23725- 25549) days: 37-219 (ng/mL)
(25550-29199) days: 0-200 (ng/mL)
(>= 29200) days: 0-323 (ng/mL)
Testing Method Used
ELISA.

Sample is stable for 3 days at 2-8°C.

Please ship samples daily.
Improvements and Prevention
Specimen Type
Serum
Fasting Required
No, but may be done with other tests that requires fasting.
Drawing and Processing
  1. Draw from a vein into a SST tubetube1
  2. Invert tube (do not shake) 1-2 times to mix adequately
  3. Let stand upright in tube rack for 30 minutes
  4. Centrifuge for 15 minutes at 3300rpm
  5. Do not leave at room temperature for more than 1 hour
  6. Keep cold in a refrigerator to maintain stability, until ready to ship
Shipping Instructions
  1. Freeze ice packs 24 hours prior to use
  2. Place ice packs inside the Styrofoam insulated kit
  3. Place processed tubes inside biohazard bag, place inside kit
  4. Seal box, print airbill and adhere to box and wait for courier to pick up
Rejection Criteria
QNS; temperature out of range upon receipt; grossly lipemic or hemolyzed; wrong specimen type; sample stability exceeded for this analyte; unlabeled or mislabeled specimen.
References

1. Höppener JW, de Pagter-Holthuizen P, Geurts van Kessel AH, Jansen M, Kittur SD, Antonarakis SE, Lips CJ, Sussenbach JS (1985). “The human gene encoding insulin-like growth factor I is located on chromosome 12”.

The information provided here is intended for educational purposes only and should not be used or substituted as medical advice. You should consult a healthcare practitioner regarding medical diagnosis or treatment.

* Vibrant™ Tests have been developed and its performance characteristics determined by the CLIA-certified laboratory performing the test. This test has not been cleared or approved by the U.S. Food and Drug Administration (FDA). Although FDA does not currently clear or approve laboratory-developed tests in the U.S., certification of the laboratory is required under CLIA to ensure the quality and validity of the tests.