Insulin Antibody (Sendout)

General Information

Lab Name
Insulin Antibody (Sendout)
Lab Code
RINSG
Epic Name
Insulin Ab
External Test Id
INAB
Description

Useful For:

  • Predicting the future development of type 1 diabetes in asymptomatic children, adolescents, and young adults, when used in conjunction with family history, human leukocyte antigen-typing, and other autoantibodies, including glutamic acid decarboxylase (GAD65) and islet cell antigen 2 (IA-2) antibodies
  • Differential diagnosis of type 1 versus type 2 diabetes
  • Evaluating diabetics with insulin resistance in patients with established diabetes (type 1 or type 2)
  • Investigation of hypoglycemia in nondiabetic subjects
References
Synonyms
Anti-Insulin, Human Insulin, INAB, Insulin Ab
Components
Code Name
RINAB Insulin Antibody

Interpretation

Method

Radioimmunoassay (RIA)

Reference Range
See individual components
Ref. Range Notes

Interpretation:

Seropositivity (> or =0.03 nmol/L) in a patient never treated with insulin is consistent with predisposition to type 1 diabetes. Seropositivity is not as informative of type 2 diabetes status as other islet cell antibodies in patients who are receiving (or have received) insulin therapy because this antibody can arise secondary to therapy. It is thought that high levels of insulin autoantibodies might contribute to insulin resistance.

A family history of type 1 diabetes, other organ-specific autoimmunity and a diabetes-permissive human leukocyte antigen phenotype strengthens the prediction of type 1 diabetes development. The detection of multiple islet cell antibodies is indicative of the likely development of future type 1 diabetes.

In patients presenting with hypoglycemia, the presence of insulin autoantibodies may indicate surreptitious insulin administration or, rarely, insulin autoantibody-related hypoglycemia. The differential diagnosis cannot be made on the basis of insulin autoantibody detection alone. C-peptide and insulin measurements are always required in addition to insulin autoantibody measurements in the diagnosis of hypoglycemia.

Interferences and Limitations

Cautions: This test should not be requested in patients who have recently received radioisotopes, therapeutically or diagnostically, because of potential assay interference. The specific waiting period before specimen collection will depend on the isotope administered, the dose given and the clearance rate in the individual patient. Specimens will be screened for radioactivity prior to analysis. Radioactive specimens received in the laboratory will be held 1 week and assayed if sufficiently decayed, or canceled if radioactivity remains.

Ordering & Collection

Specimen Type
Blood
Collection

5 mL blood in a RED TOP tube

Also Accepted: GOLD SST

Handling Instructions

Outside Laboratories: Centrifuge sample and transfer serum to a separate plastic vial. Refrigerate serum while awaiting shipment. Transport with a cold pack.

Stability: Refrigerated (preferred): 28 days; Frozen: 28 days; Ambient: 72 hours.

Reject Due To: Gross hemolysis, gross lipemia, or gross icterus.

Quantity
Requested: 1.5 mL serum
Minimum: 1 mL serum

Processing

Receiving Instructions

Centrifuge sample and transfer serum to a separate plastic vial. Refrigerate serum.

Sendouts:

  • Order Mayo Test: INAB
  • Interfaced: Yes [Interface: 601; Worksheet: MARF]

Stability: Refrigerated (preferred): 28 days; Frozen: 28 days; Ambient: 72 hours.

Reject Due To: Gross hemolysis, gross lipemia, or gross icterus.

Misc Sendout

Performance

Lab Department
Sendouts Mayo Lab (RF)(MARF)
Frequency
Performed: Sunday, Wednesday. Report Available: 3-9 days from sample receipt at Mayo Clinic Laboratories.
Available STAT?
No
Performing Location(s)
Sendout Mayo Clinic Laboratories
800-533-1710

200 First Street Southwest
Rochester, MN 55901

Billing & Coding

CPT Codes
86337
LOINC
60463-7
Interfaced Order Code
UOW2419