Sign in →

Test Code LAB6649 Hypoglycemic Agent Screen, Serum

Additional Codes

 

Test Name in EPIC EPIC Test Code Mnemonic Mayo Test ID
HYPOGLYCEMIC AGENT SCRN, S LAB6649 HYPOG HYPOG

 

Reporting Name

Hypoglycemic Agent Screen, S

Useful For

Evaluation of suspected insulinoma characterized by hypoglycemia and increased serum insulin concentration

 

Detecting drugs that stimulate insulin secretion

 

Drugs detected by this procedure are:

-The first-generation sulfonylureas: chlorpropamide (Diabinese), tolazamide, and tolbutamide (Orinase)

-The second-generation sulfonylureas: glimepiride (Amaryl), glipizide (Glucotrol), and glyburide (Glibenclamide)

-The meglitinides: repaglinide (Prandin) and nateglinide (Starlix)

-The thiazolidinediones: pioglitazone (Actos) and rosiglitazone (Avandia)

 

This test is not intended for therapeutic drug monitoring but could be used to monitor compliance.

Method Name

Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Specimen Type

Serum Red


Specimen Required


Patient Preparation: Specimen must be collected during an episode of hypoglycemia.

Supplies: Sarstedt Aliquot Tube, 5 mL (T914)

Collection Container/Tube: Red top (serum gel/SST are not acceptable)

Submission Container/Tube: Plastic vial

Specimen Volume:1.5 mL

Collection Instructions: Centrifuge and aliquot serum into a plastic vial.


Specimen Minimum Volume

0.5 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Serum Red Frozen (preferred) 28 days
  Refrigerated  28 days
  Ambient  7 days

Reject Due To

Gross hemolysis OK
Gross lipemia OK
Gross icterus OK

Reference Values

Negative

Screening cutoff concentrations

Chlorpropamide: 100 ng/mL

Glimepiride: 20 ng/mL

Glipizide: 5 ng/mL

Glyburide: 5 ng/mL

Nateglinide: 5 ng/mL

Pioglitazone: 20 ng/mL

Repaglinide: 5 ng/mL

Rosiglitazone: 20 ng/mL

Tolazamide: 50 ng/mL

Tolbutamide: 20 ng/mL

 

Note: If a drug is detected at a concentration greater than the cutoff, the report will indicate that specific drug is positive. The test cutoff listed for each drug is lower than the concentration that will cause increased insulin and decreased glucose.

Day(s) Performed

Monday, Wednesday, Friday

CPT Code Information

80377

G0480-(if appropriate)

LOINC Code Information

Test ID Test Order Name Order LOINC Value
HYPOG Hypoglycemic Agent Screen, S 68318-5

 

Result ID Test Result Name Result LOINC Value
21295 Chlorpropamide 48329-7
21298 Glimepiride 48325-5
21299 Glipizide 48326-3
21300 Glyburide 48327-1
609767 Nateglinide 49487-2
609768 Pioglitazone 100351-6
21301 Repaglinide 48328-9
609769 Rosiglitazone 100352-4
21296 Tolazamide 21566-5
21297 Tolbutamide 21567-3

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.

Clinical Information

The metabolic and hormonal profiles of insulinoma and sulfonylurea-induced hypoglycemia are identical. Therefore, in the evaluation of the hypoglycemic patient, the possible use of oral hypoglycemic agents as the cause for low blood glucose and elevated serum insulin must be considered. Absence of hypoglycemic drugs in serum during an episode of low blood glucose should be demonstrated before considering pancreatic exploration for suspected insulinoma.

Interpretation

Use of hypoglycemic agents outside of the context of treatment of type 2 diabetes is likely to cause hypoglycemia associated with elevated serum insulin. Patients presenting with hypoglycemia due to ingestion of a first-, second-, or third-generation hypoglycemic agents will have drug present in serum greater than the minimum effective concentration (see Reference Values). Presence of drug indicates that the patient has recently ingested a hypoglycemic agent.

Cautions

Proper interpretation requires that the specimen be collected during or close to the time of a hypoglycemic episode. Drugs will not be detected (and are not likely to be present) if blood is drawn when blood glucose is normal in nondiabetic patients.

 

All drugs that stimulate insulin secretion undergo extensive metabolism before excretion. The parent drug is therefore not present in urine. Blood serum is the specimen of choice for detecting use of the hypoglycemic drugs; urine or plasma is not an acceptable specimen.

 

This screen does not include the first-generation sulfonylurea acetohexamide.

 

Other drugs that do not induce hypoglycemia, thiazolidinediones such as troglitazone and lobeglitazone, and are designed to make tissues more sensitive to insulin are not included in this screen test.

 

Drugs that lower blood glucose through mechanisms not related to stimulation of insulin secretion, such as acarbose, metformin, and miglitol, are not included in this screen test.

Method Description

Serum specimens are subjected to organic extraction. The extract is analyzed by liquid chromatography tandem mass spectrometry.(Unpublished Mayo method)

Report Available

2 to 6 days

Forms

If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) with the specimen.

Specimen Retention Time

14 days