Hemoglobin Subtype Analysis (Screening) by Immunoassay
This test measures different types of hemoglobin in your blood to help identify conditions like sickle cell disease or other hemoglobinopathies.
["A simple blood test to check for abnormal hemoglobin variants that may affect your health."]
Key facts at a glance
- LOINC
- 34618-9
- Short code
- Hgb Spec Ql
- Synonyms
- Hgb Spec Ql
- Category
- hematology
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 12
- Ref high
- 17.5
- Critical range
- 7 N/A – 20 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85018
- SNOMED
- 900000000000003004
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Matters
Hemoglobin is the protein in red blood cells that carries oxygen. Certain types of hemoglobin can cause health problems, such as anemia, pain crises, or organ damage. This screening helps detect rare or inherited hemoglobin disorders early.
What to Expect Before the Test
You’ll have a small needle inserted into your arm to draw blood. The process takes about 5 minutes. No special preparation is needed, but let your doctor know if you’re on blood thinners or have a history of bleeding issues.
Common Conditions This Test Helps Diagnose
This screening may be used if you have symptoms like fatigue, frequent infections, or unusual pain (e.g., in the chest or abdomen). It’s also part of prenatal testing for families with a history of hemoglobin disorders.
What the Results Mean
Results show the proportion of different hemoglobin types. Abnormal patterns may indicate conditions like sickle cell trait (a mild form) or sickle cell disease (a severe inherited disorder). Your doctor will interpret results in the context of your symptoms and family history.
Reference range
Adult males: 13.5-17.5 g/dL; Females: 12.0-16.0 g/dLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Early detection of hemoglobin variants can prevent complications like organ damage, stroke, or severe pain episodes. For example, sickle cell trait is usually harmless but can cause problems under stress (e.g., high altitude, dehydration). Confirmatory tests may follow if screening results are abnormal.
Short name
Hb Subtype Screen
Frequently asked questions
What triggers this screening test?
How often should I get this test?
Can I eat or drink before this test?
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