Test Catalog

Test ID: IGFGP    
Insulin-Like Growth Factor 1 (IGF1), LC-MS and Insulin-Like Growth Factor-Binding Protein 3 (IGFBP3) Growth Panel

Method Description Describes how the test is performed and provides a method-specific reference

Insulin-Like Growth Factor 1 (IGF1), liquid chromatography-mass spectrometry (LC-MS):

Stable isotope labeled internal standard is added to patient samples. IGF1 is then extracted by selective precipitation. The extracted samples are analyzed by LC-MS. This is a laboratory-developed MS test, calibrated against the First World Health Organization International standard for IGF1 (02/254).(Unpublished Mayo method)


Insulin-Like Growth Factor-Binding Protein 3 (IGFBP3):

The IMMULITE 2000 IGFBP3 is a solid-phase, enzyme-linked chemiluminescent immunoassay based on murine monoclonal antibodies. The patient sample and alkaline phosphatase-conjugated anti-IGFBP3 antibodies are simultaneously incubated with an antibody-coated bead. During this time, IGFBP3 in the sample forms an antibody sandwich complex that binds to the streptavidin on the bead. Unbound enzyme conjugate is then removed by washing, after which substrate is added. The chemiluminescent substrate, a phosphate ester of adamantyl dioxetane, undergoes hydrolysis in the presence of alkaline phosphatase to yield an unstable intermediate. The continuous production of this intermediate results in the sustained emission of light. The photon output is directly proportional to the concentration of IGFBP-3 in the sample.(Package insert: IMMULITE 2000 IGFBP-3 Siemens Medical Solutions Diagnostics, Los Angeles, CA, PIL2KGB-11, 2008-07-29)

PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.

IGFB3: Monday through Friday 5 a.m.-12 a.m., Saturday 6 a.m.- 6 p.m.

IGFMS: Monday through Friday, Sunday; 12 p.m.

Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.

Same day/1 day for IGFB3 and 2 day for IGFMS

Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Clinic Laboratories until the release of the test result

3 days

Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

14 days

Performing Laboratory Location Indicates the location of the laboratory that performs the test