IGF-1, LC/MS

Test Code

IGF-I

Quest Code

16293

CPT Codes
84305

Preferred Specimen

0.5 mL serum

Minimum Volume

0.3 mL

Instructions

Collect blood in a red-top or SST vacutainer. For red-top vacutainers, allow blood to clot (10-15 minutes) at room temperature. Separate serum from cells and refrigerate.

Transport Temperature

Refrigerated (cold packs)

Specimen Stability

Room temperature: 48 hours
Refrigerated: 7 days
Frozen: 60 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Moderate hemolysis

Methodology
Liquid Chromatography/Mass Spectrometry (LC/MS)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

A.M.

Reference Range

Pediatric	Male (ng/mL)	Female (ng/mL)
<1 Years	14-142	17-185
1-1.9 Years	12-134	15-175
2-2.9 Years	12-135	16-179
3-3.9 Years	30-155	38-214
4-4.9 Years	28-181	34-238
5-5.9 Years	31-214	37-272
6-6.9 Years	38-253	45-316
7-7.9 Years	48-298	58-367
8-8.9 Years	62-347	76-424
9-9.9 Years	80-398	99-483
10-10.9 Years	100-449	125-541
11-11.9 Years	123-497	152-593
12-12.9 Years	146-541	178-636
13-13.9 Years	168-576	200-664
14-14.9 Years	187-599	214-673
15-15.9 Years	201-609	218-659
16-16.9 Years	209-602	208-619
17-17.9 Years	207-576	185-551

Adult	(ng/mL)
18-19.9 Years	108-548
20-24.9 Years	83-456
25-29.9 Years	63-373
30-39.9 Years	53-331
40-49.9 Years	52-328
50-59.9 Years	50-317
60-69.9 Years	41-279
70-79.9 Years	34-245
>80 Years	34-246

Z-Score (Male)	-2.0 - +2.0 SD
Z-Score (Female)	-2.0 - +2.0 SD

Pediatric Tanner Stages

See Laboratory Report

Clinical Significance

Insulin-like Growth Factor 1 (IGF-1, or Somatomedin C), a protein involved in stimulating somatic growth, is regulated principally by Growth Hormone (GH) and nutritional intake. IGF-1 is transported in serum by several proteins; this helps maintain relatively high IGF-1 plasma levels and minimizes fluctuations in serum IGF-1 concentrations.
Measuring IGF-1 is useful in several growth-related disorders. Dwarfism caused by deficiency of growth hormone (Hypopituitarism) results in decreased serum levels of IGF-1, while acromegaly (growth hormone excess) results in elevated levels of IGF-1. IGF-1 measurements are also helpful in assessing nutritional status; levels are reduced in undernutrition and restored with a proper diet

Performing Laboratory
Quest Diagnostics Nichols Institute
33608 Ortega Highway
San Juan Capistrano, CA 92690-6130

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.