ARUP's Laboratory Test Directory

Insulin, Free and Total : 0070155

Mnemonic: INS F&T

Ordering Recommendation: Not recommended to diagnose diabetes mellitus.
Methodology: Quantitative Ultrafiltration/Quantitative Chemiluminescent Immunoassay
Performed: Mon, Thu, Sat
Reported: 2-4 days
Specimen Required: Patient Prep: Fasting specimen preferred; reference intervals established for fasting specimens.

Collect: Serum separator tube. Also acceptable: Lavender (EDTA), or pink (K2EDTA).

Specimen Preparation: Transfer 2 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 1.1 mL)

Storage/Transport Temperature: Frozen. Separate specimens must be submitted when multiple tests are ordered.

Unacceptable Conditions: Heparinized specimens. Sodium fluoride/potassium oxalate plasma. Hemolyzed specimens.

Stability (collection to initiation of testing): After separation from cells: Ambient: 8 hours; Refrigerated: 1 week; Frozen: 1 month
Reference Interval:
 
Test Number Components Reference Interval
 Insulin, Free By report
 Insulin, Total By report

Interpretive Data: This test reacts on a nearly equimolar basis with the analogs insulin aspart, insulin glargine, and insulin lispro. Insulin detemir exhibits approximately 50 percent cross-reactivity. Test reactivity with insulin glulisine is negligible (< 3 percent). To convert to pmol/L, multiply µIU/mL by 6.0.
CPT Code(s): 83525; 83527