HLA-B1502 Genotyping (Carbamazepine) Test: Booking, Price, and Results
About HLA-B1502 Genotyping (Carbamazepine) Test: Booking, Price, and Results
| Field | Value |
|---|---|
| Also Known As | HLA-B*15:02 genotyping, HLA-B1502 typing, Carbamazepine sensitivity test, Tegretol hypersensitivity test |
| Sample Type | Peripheral blood (whole blood in EDTA tube) |
| Fasting Required | No fasting required |
| Report Time | 35 days |
| Recommended For | All genders and ages; particularly recommended for individuals of Asian ancestry being considered for carbamazepine or oxcarbazepine therapy |
| Price | Starting at ₹5,400 |
What is an HLA-B1502 Genotyping (Carbamazepine) Test?
The HLA-B1502 genotyping (carbamazepine) test is a genetic test that checks whether you carry a specific gene variant called HLA-B*15:02. Carrying this variant is associated with a higher risk of severe skin reactions when taking carbamazepine, a medicine used to treat epilepsy, nerve pain, and certain other conditions. Doctors order this test before starting carbamazepine therapy, particularly for patients of Asian ancestry. Also known as the carbamazepine sensitivity test, it uses a peripheral blood sample collected in an EDTA tube.
What Does an HLA-B1502 Genotyping (Carbamazepine) Test Measure?
The HLA-B1502 genotyping test analyses a single genetic marker. Here is what it looks for:
| Parameter | What it Means |
|---|---|
| HLA-B*15:02 allele | A human leucocyte antigen (HLA) gene variant linked to a higher risk of severe drug reactions when taking carbamazepine or oxcarbazepine |
The test uses a method called Sanger sequencing to determine whether this specific genetic variant is present or absent in your DNA.
Why is an HLA-B1502 Genotyping (Carbamazepine) Test Done?
This test is ordered before a doctor prescribes carbamazepine or related medicines. It helps identify patients who may be at risk of serious adverse reactions.
Common Symptoms That May Require This Test
A doctor may order this test when carbamazepine is being considered to manage any of the following conditions:
- Seizures associated with epilepsy
- Trigeminal neuralgia (sharp nerve pain in the face)
- Bipolar disorder symptoms
- Diabetic neuropathy (nerve damage caused by diabetes)
Conditions This Test Can Help Detect
The test specifically screens for genetic risk before carbamazepine therapy begins:
- Risk of Stevens-Johnson syndrome (SJS), a severe reaction affecting the skin and mucous membranes
- Risk of toxic epidermal necrolysis (TEN), a more severe form of the same type of reaction
- The HLA-B*15:02 variant is strongly linked to both SJS and TEN in patients taking carbamazepine or oxcarbazepine
How to Prepare and What to Expect
No special preparation is needed for this test. The following details explain what you can expect before and during sample collection.
Do You Need to Fast?
No, fasting is not required for the HLA-B1502 genotyping (carbamazepine) test. You may eat and drink normally before your appointment.
Practical Tips Before Your Test
Here are a few simple steps to help ensure an accurate result:
- Bring a detailed clinical history, including your symptoms, previous test results, and family history, as this is required for the test
- Inform the laboratory of any current medications you are taking
- Let your doctor know if you have ever had a haematopoietic stem cell transplant (a blood or bone marrow transplant from another person), as this can interfere with results
- Inform the laboratory if you have received a recent blood transfusion, as this may also affect results
- Carry any prescription or referral letter from your doctor
Step-by-Step Procedure
The sample collection for this test is a straightforward blood draw. Here is what to expect:
- A trained phlebotomist will clean the inside of your elbow with an antiseptic swab.
- A small needle is used to draw approximately 2 ml of blood from a vein in your arm.
- The blood is collected into a lavender-coloured EDTA tube.
- The tube is gently inverted several times to mix the blood with the anticoagulant inside.
- The whole blood sample is sent to the laboratory in its original tube without separation.
- In the laboratory, DNA is extracted from your sample and analysed by Sanger sequencing to detect the HLA-B*15:02 variant.
Factors That Can Affect Accuracy
Certain factors can influence the reliability of the test result:
- A prior allogeneic stem cell transplant (from another person) can affect the result, as donor DNA may be present in the blood
- Haemolysis (breakdown of red blood cells) in the sample can interfere with testing
- A clotted sample or insufficient blood volume may make the sample unsuitable
- Blood collected in sodium or lithium heparin tubes is not acceptable for this test
- Recent blood transfusions may affect the result
Understanding Your HLA-B1502 Genotyping (Carbamazepine) Test Results
Your doctor will review your results alongside your medical history and current health status. The table below shows how results are generally interpreted.
| Result | Interpretation |
|---|---|
| Negative (Not detected) | Low risk of carbamazepine-induced SJS or TEN; your doctor may consider carbamazepine therapy with standard monitoring |
| Positive (Detected) | Increased risk of carbamazepine-induced SJS or TEN; carbamazepine is generally avoided, and your doctor will discuss alternative treatments |
Disclaimer: These ranges are general guidelines. Your doctor will interpret your results based on your age, health history, and other factors. Always consult a qualified healthcare professional for personalised medical advice.
Results During Special Conditions
Certain circumstances can affect how your result should be read:
- If you have had a haematopoietic stem cell transplant from another person, the result may reflect the donor's HLA type rather than your own.
- The significance of a positive result varies by ethnic background. The HLA-B*15:02 variant is most common in people of Asian descent (around 10% in Han Chinese and Taiwanese populations). In India, prevalence ranges from 0% to 6% across different communities, with some South Indian populations showing rates of around 7%. The variant is much rarer in people of African or European ancestry.
How to Maintain Healthy Levels
Because this is a genetic test, the result does not change with lifestyle choices. Here is how to act on your result:
- If your result is positive, work closely with your doctor to identify safe and effective alternative medications.
- Carry a record of your HLA-B*15:02 status so that any future healthcare provider is aware of it.
- Keep your genetic test report with your other important medical documents for easy reference.
Lupin Diagnostics HLA-B1502 Genotyping (Carbamazepine) Test Price
The HLA-B1502 genotyping test cost at Lupin Diagnostics starts at ₹5,400. This test requires a visit to a Lupin Diagnostics centre; home collection is not available for this test.
| City | Approximate Price (₹) |
|---|---|
| BHOPAL | 5400 |
| CHENNAI | 5400 |
| HYDERABAD | 5400 |
| KOLKATA | 5400 |
| NAVI MUMBAI | 5400 |
| PUNE | 5400 |
Disclaimer: Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
The HLA-B1502 genotyping test online booking process at Lupin Diagnostics is straightforward:
- Select the test on the Lupin Diagnostics website.
- Choose your city and preferred centre location.
- Visit the centre at your scheduled time for sample collection.
- Receive your report via email or WhatsApp within the stipulated turnaround time.
Frequently Asked Questions
The HLA-B1502 genotyping (carbamazepine) test is a genetic test that checks whether you carry the HLA-B*15:02 gene variant. This variant is linked to a higher risk of serious skin reactions, specifically Stevens-Johnson syndrome and toxic epidermal necrolysis, in patients who take carbamazepine. It is usually ordered before starting this medication.
This test is particularly recommended for patients of Asian ancestry who are being considered for carbamazepine or oxcarbazepine therapy. Doctors may also consider it for patients of other ethnic backgrounds, depending on their clinical situation. The decision is made by your treating doctor.
No, fasting is not required. You can eat and drink normally before your appointment. The test simply requires a small blood sample from a vein in your arm.
At Lupin Diagnostics, the report for the HLA-B1502 genotyping test is delivered within 35 days of sample collection. The extended turnaround time reflects the specialised Sanger sequencing method used to analyse the sample.
A positive result means the HLA-B*15:02 variant was detected in your blood. This indicates a higher genetic risk of developing severe skin reactions if you take carbamazepine. Your doctor will discuss alternative medications with you. A positive result does not mean you are currently unwell.
No. Your genetic make-up does not change over time, so this is a one-time test. The only exception is if you have had a stem cell transplant from another person, which may affect future test results. In that case, speak to your doctor.
The HLA-B1502 genotyping test requires a visit to a Lupin Diagnostics centre. Home collection is not available for this test due to the specialised handling and storage requirements of the sample. You can book your appointment easily through the Lupin Diagnostics website.
HLA-B1502 Genotyping (Carbamazepine) Test: Booking, Price, and Results
