Hemoglobin A1c (HbA1c) with Immunoassay Probe Measurement
This test measures the percentage of hemoglobin that is coated with sugar (glycated hemoglobin), reflecting your average blood sugar levels over the past 2–3 months.
["Helps track long-term diabetes control and adjust treatment plans."]
Key facts at a glance
- LOINC
- 105794-2
- Short code
- CRVIM
- Synonyms
- blaVIM Ct Bld Pos Qn NAA+probe
- Category
- chemistry
- Sample
- whole-blood
- Container
- Positive blood culture bottle (aerobic or anaerobic) or sterile container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- probe-amp-tar
- CPT
- 87798
- SNOMED
- 409826009
- Specimen volume
- 1-10 mL positive blood culture broth; minimum 0.5 mL
- Stability
- Room temperature: 24 hours; Refrigerated (2-8°C): 7 days; Frozen (-70°C): 30 days. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 2–8 hours
- Order
- routine
What This Test Measures
HbA1c reflects how your blood sugar levels have been managed over time. It binds to hemoglobin in red blood cells, forming glycated hemoglobin, which remains stable in circulation for the lifespan of those cells (about 3–4 months). This provides a snapshot of your average glucose exposure during that period.
Why It’s Done
Doctors use HbA1c to diagnose diabetes, monitor treatment effectiveness, and assess overall blood sugar management in people with type 1 or type 2 diabetes.
How It’s Performed
A small blood sample is drawn from your arm, typically using a fingerstick. The sample is processed to measure the glycated hemoglobin percentage via an immunoassay method, which detects specific antibodies bound to glycated hemoglobin.
What to Expect Before or After
No special preparation is needed. You may feel slight discomfort from the needle, but it usually resolves quickly. Results are typically available within 24 hours.
Reference range
Not Detected (Negative). Reported as cycle threshold (Ct) value when positive; lower Ct values indicate higher bacterial load.N/A
No special patient preparation required. Specimen should be collected prior to initiation of antimicrobial therapy when possible to maximize detection sensitivity.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
HbA1c is a critical tool for diabetes management because it provides a more reliable measure of long-term glucose control than daily blood sugar readings. A higher HbA1c percentage correlates with poorer glycemic control and increased risk of diabetes complications, such as nerve damage, kidney disease, or cardiovascular issues. Regular monitoring helps prevent these risks by allowing timely adjustments to medication or lifestyle.
Short name
HbA1c (Blood)
Frequently asked questions
How often should I get this test?
What do my results mean?
Can lifestyle changes affect HbA1c results?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy