Hemoglobin A1C (by HPLC)

General Information

Lab Name
Hemoglobin A1C by HPLC
Lab Code
A1C
Epic Name
Hemoglobin A1C, HPLC
Description

A1c HPLC test utilizes principles of ion-exchange high-performance liquid chromatography (HPLC). HbA1c testing can be used to diagnose diabetes, with a value of ≥6.5% (≥48 mmol/mol), and prediabetes, with an HbA1c level of 5.7–6.4% (39–47 mmol/mol). HbA1c should be measured routinely in most individuals with diabetes mellitus to document their degree of glycemic control, with the goal HbA1c <7.0%. Detection and treatment of pre-diabetes may reduce or eliminate the risk of developing Type 2 diabetes and related complications.

Synonyms
Glycated Hemoglobin, Glycohemoglobin, Glycosylated Hemoglobin, HBA1C by HPLC, HGBA1C
Components

Interpretation

Method

High Performance Liquid Chromatography (HPLC)

Reference Range
Units: %
Female Male
AgeRange AgeRange
0-4.0-5.6 0-4.0-5.6

Effective date: 10/01/2024

Ref. Range Notes

Prediabetes: 5.7 - 6.4%
Diabetes: >6.4%
Glycemic control for adults with diabetes: <7.0%

Interferences and Limitations

The HbA1c test should not be used to diagnose diabetes in patients with the following conditions:

  • Recent blood loss
  • Recent transfusion
  • Significant iron deficiency
  • Hemolytic anemia or other hemolytic disease
  • Hemoglobinopathies and thalassemias
  • Malignancies or severe chronic hepatic and renal disease

Hemoglobin F concentration up to 30% does not interfere with the test.

Ordering & Collection

Specimen Type
Blood
Collection

3 mL LAVENDER HEMOGARD tube

Unacceptable: Non-human specimen

Handling Instructions

Instructions for Outside Clients:

This test is for ALL routine HbA1c's from blood tubes sent to the lab. (Preliminary results before clinic visit are available only at Roosevelt and South Lake Union laboratories. See rapid Point of Care test A1CRPD.) Non-human specimens cannot be assayed as the method cannot identify non-human hemoglobins.

Stability: Room Temperature 4 days; Refrigerated 6 days

Quantity
Requested: 3 mL whole blood
Minimum: 1 mL whole blood

Processing

Receiving Instructions

Refrigerate whole blood in Red Cell Disorders (RCD) rack upon receipt or addon.

Unacceptable: Other anticoagulants, Frozen specimens

Stability: Room Temperature 4 days; Refrigerated 6 days

Processing Staff: RCD techs may reflex to the alternate method A1CRPD in cases with interference by hemoglobin variants.

Misc Sendout

Performance

Lab Department
Red Cell Disorders(RCD)
Frequency
Frequency: Monday-Friday, except holidays. Samples sent to lab are generally run next working day.
Available STAT?
No
Performing Location(s)
HMC Red Cell Disorders
206-520-4600

325 9th Ave, Rm # GWH-47, Seattle, WA 98104-2420

Billing & Coding

CPT Codes
83036
LOINC
4548-4
Interfaced Order Code
UOW100
Interfaced Result Code
UOW100