Preferred Sample Type
Suitable Specimen Types
- Serum
- Li Hep Plasma
Sample Processing in Laboratory
Usual
Sample Preparation
Centrifuge and separate serum, store frozen. Serum stable at 4C for up to 8 days, thereafter store frozen
Turnaround Time
5 daysSample Stability
4C for 8 days, -20C thereafter
IGF-1 (Insulin-like Growth Factor)
General Information
Insulin-like growth factor - 1 (IGF-1) has sequence similarity to insulin, and similar biological functions as insulin e.g. inhibits lipolysis, increases glucose oxidation in adipose tissues. Other functions include growth-promoting effects on cartilage and enhanced synthesis of proteoglycans and collagen. IGF-1 levels normally are low in early childhood, increase gradually during childhood, peak during puberty, and then decline in adult life. The IGF-1 test is an indirect measure of the average amount of growth hormone (GH) being produced by the body. The concentration of IGF-1 is stable throughout the day, making it a useful indicator of average GH levels (as GH has pulsatile secretion).
Patient Preparation
None
Notes
IGF-1 is measured to help diagnose the cause of growth abnormalities and to evaluate pituitary function. (Formerly known as somatomedin)
IGF-1 concentrations are high in states of Growth Hormone excess and low in states of Growth Hormone deficiency.
Serum levels of IGF-1 are also low in patients with acute or chronic protein or calorie deprivation.
Reference Range
Reference range provided by referral laboratory. Please note new reference range 27/09/2016 (analysed by IDS iSYS assay)
|
Age |
Female |
Male |
||
|
LLN (nmol/L) |
ULN (nmol/L) |
LLN (nmol/L) |
ULN (nmol/L) |
|
|
0 |
2.3 |
19.1 |
1.9 |
19.7 |
|
1 |
2.6 |
20.9 |
2.4 |
23.4 |
|
2 |
3.0 |
23.1 |
2.8 |
26.7 |
|
3 |
3.5 |
26.0 |
3.3 |
29.3 |
|
4 |
4.2 |
29.2 |
3.7 |
31.6 |
|
5 |
4.8 |
32.3 |
4.1 |
33.9 |
|
6 |
5.4 |
35.3 |
4.7 |
36.8 |
|
7 |
6.2 |
39.1 |
5.4 |
40.7 |
|
8 |
7.4 |
44.5 |
6.4 |
46.0 |
|
9 |
8.9 |
51.9 |
7.6 |
52.5 |
|
10 |
10.9 |
60.9 |
9.1 |
60.0 |
|
11 |
13.0 |
70.4 |
10.7 |
67.6 |
|
12 |
15.0 |
78.4 |
12.2 |
74.2 |
|
13 |
16.5 |
83.4 |
13.5 |
79.0 |
|
14 |
17.4 |
84.8 |
14.5 |
81.3 |
|
15 |
17.5 |
82.7 |
15.0 |
80.9 |
|
16 |
17.0 |
77.9 |
15.1 |
78.4 |
|
17 |
16.1 |
71.5 |
14.8 |
74.2 |
|
18 |
14.9 |
64.5 |
14.3 |
69.0 |
|
19 |
13.7 |
57.8 |
13.6 |
63.4 |
|
20 |
12.7 |
52.1 |
12.8 |
58.0 |
|
21-25 |
11.0 |
42.3 |
10.9 |
45.1 |
|
26-30 |
10.1 |
35.5 |
9.8 |
36.0 |
|
31-35 |
9.5 |
32.0 |
9.3 |
31.6 |
|
36-40 |
8.9 |
29.5 |
9.1 |
29.6 |
|
41-45 |
8.1 |
26.9 |
8.3 |
27.5 |
|
46-50 |
7.4 |
25.4 |
7.7 |
26.4 |
|
51-55 |
6.9 |
25.0 |
7.3 |
26.3 |
|
56-60 |
5.9 |
22.7 |
6.6 |
25.4 |
|
61-65 |
5.4 |
22.0 |
6.2 |
25.0 |
|
66-70 |
5.1 |
22.0 |
6.0 |
25.5 |
|
71-75 |
4.7 |
21.7 |
5.4 |
24.5 |
|
76-80 |
4.6 |
22.1 |
5.1 |
24.0 |
|
81-85 |
4.6 |
23.4 |
4.8 |
23.8 |
|
86-90 |
4.3 |
23.4 |
4.6 |
23.8 |
Specifications
- EQA Scheme?: Yes