Hemoglobin (Hb) A1c
Test ID: A881
HbA1c is glycated hemoglobin, which forms when hemoglobin within red blood cells joins with glucose. HbA1c levels reflect the average blood glucose level during the preceding 2-3 months. Measurement of HbA1c is useful for assessing diabetes risk, diagnosis, and control, as well as part of an evaluation of cardiac health.
How to order a test
- Glycated hemoglobin
What is Included?
Measurement of hemoglobin A1c (HbA1c) and total hemoglobin (THb) levels in a blood sample by enzymatic methodology. These two concentrations are used to determine the %HbA1c (National Glycohemoglobin Standardization Program, NGSP units) or the hemoglobin fraction in mmol/mol (International Federation of Clinical Chemistry and Laboratory Medicine, IFCC units).
1 – 3 business days
The turnaround time is not guaranteed. The average turnaround time is 1 – 3 business days from the date that the sample arrives at the laboratory. Shipping time for the sample is not included. Additional time is required if the case requires confirmatory or reflex testing, or if the sample is insufficient, or if a recollection is required.
Additional Information and Resources
Preparation Before Specimen Collection
50 μL in a microtainer
Microtainer (regular blood tube)
This test requires a blood sample from a finger prick. All supplies for sample collection are provided in the kit.
- First wash and dry hands. Warm hands aid in blood collection.
- Clean the finger prick site with the alcohol swab and allow to air dry.
- Use the provided lancet to puncture the skin in one quick, continuous and deliberate stroke.
- Wipe away the first drop of blood.
- Massage hand and finger to increase blood flow to the puncture site. Angle arm and hand downwards to facilitate blood collection on the fingertip.
- Drip blood into the microtainer tube.
- Dispose of all sharps safely and return sample to the laboratory in the provided prepaid return shipping envelope.
NOTES: Avoid squeezing or ‘milking’ the finger excessively. If more blood is required and blood flow stops, perform a second skin puncture on another finger. Do not touch the fingertip.
Maintain specimen at temperatures between 2°C and 30°C during storage and transport.
Blood samples can be refrigerated or kept at room temperature for up to 7 days.
Causes for Rejection
- Incorrect or incomplete patient identification
- Incorrect specimen collection
- Inappropriate storage and transport conditions
- Incorrect specimen volume
- Gross hemolysis
To measure hemoglobin A1c (HbA1c) levels in a blood sample for the evaluation of glucose control to assess diabetes risk, diagnosis, and control. Evaluation of HbA1c levels is also beneficial in the evaluation of cardiac health. HbA1c levels reflect the average blood glucose level during the preceding 2-3 months.
- This report is not intended for use in medico-legal applications.
- These results should be interpreted in conjunction with other laboratory and clinical information.
- Correct specimen collection and handling is required for optimal assay performance.
- Interferences from medication or endogenous substances may affect results.
- Hematocrit disorders may interfere with assay results.
- HbA1c levels are decreased in cases of shortened red blood cell survival, including due to haemolytic anemia, sickle cell disorders, pregnancy, and significant blood loss. Hence, this assay cannot be used to diagnose diabetes in individuals from each of these categories.
- Severe chronic hepatic and renal disease, and malignancies may interfere with this assay.
- This assay should not replace glucose testing in patients with Type 1 diabetes, pediatric patients, or pregnant women.
- Abnormal amounts of fetal hemoglobin (HbF) will interfere with this assay.
Enzymatic (Alinity c Hemoglobin A1c assay)
Hemoglobin A1c (HbA1c) levels and total hemoglobin (THb) levels are determined in this assay. The final result is expressed as %HbA1c (NGSP units).
|Prediabetes (increased risk of diabetes)||5.7 – 6.4|
|Supports a diabetes diagnosis||≥ 6.5|
|Recommended goal for diabetic adults||< 7.0|
These reference ranges were obtained from the Alinity c Hemoglobin A1c package insert, which follow recommendations from the American Diabetes Association (ADA).