Hepatitis B Surface Antigen (HBsAg) Confirmatory Test: Booking, Price, and Results
About Hepatitis B Surface Antigen (HBsAg) Confirmatory Test
| Field | Value |
|---|---|
| Also Known As | HBsAg Neutralisation Assay, Hepatitis B Neutralisation Assay, Confirmatory HBsAg Test, HBs Antigen Confirmation |
| Sample Type | Venous blood (serum or plasma) |
| Fasting Required | No fasting required |
| Report Time | 1 to 3 days |
| Recommended For | All genders and ages; individuals with a reactive or positive HBsAg screening result |
| Price | Starting at ₹250 |
What Is a Hepatitis B Surface Antigen (HBsAg) Confirmatory Test?
The Hepatitis B Surface Antigen Confirmation test is a follow-up blood test performed when an initial HBsAg screening result comes back reactive. It uses a neutralisation method to verify whether that reactive result reflects a true hepatitis B virus (HBV) infection or a false positive. The test is also referred to as the Hepatitis B Neutralisation Assay or the HBsAg Neutralisation Assay. A venous blood sample, typically serum or plasma, is used for the analysis.
What Does a Hepatitis B Surface Antigen (HBsAg) Confirmatory Test Measure?
The confirmatory HBsAg test examines two key elements to reach a definitive result. The test analyses whether the HBsAg reactivity seen during initial screening can be neutralised in the laboratory using a specific anti-HBs-containing reagent.
Here is what the test evaluates:
- HBsAg presence: A protein found on the outer surface of the hepatitis B virus. Its confirmed presence points to an active HBV infection.
- Neutralisation result: The laboratory adds a neutralising reagent to the sample. If reactivity is abolished compared to a control reaction, the result is confirmed positive.
- Percentage neutralisation: A specimen showing 50% or greater neutralisation between the pre-treated sample and the diluent-treated control is confirmed positive for HBsAg.
Why Is a Hepatitis B Surface Antigen (HBsAg) Confirmatory Test Done?
The HBs antigen confirmation test is ordered when a screening test raises a flag. Understanding the reasons helps patients know what to expect.
Common Symptoms That May Require This Test
A doctor may recommend an HBsAg screening followed by confirmatory testing if a patient presents with the following symptoms:
- Persistent fatigue or tiredness without an obvious cause
- Jaundice (yellowing of the skin or eyes)
- Dark-coloured urine or pale, clay-coloured stools
- Nausea, vomiting, or abdominal pain
- Unexplained loss of appetite
- Low-grade fever
- Joint pain
Conditions This Test Can Help Detect
The HBsAg Confirmatory Test can help identify or rule out the following conditions:
- Acute Hepatitis B infection
- Chronic Hepatitis B infection
- Chronic HBV carrier state
- Liver complications linked to long-term HBV infection, including cirrhosis and hepatocellular carcinoma (liver cancer)
- False positive results from the initial HBsAg screening
Hepatitis B Surface Antigen (HBsAg) Confirmatory Test During Pregnancy
Pregnant women are routinely screened for HBV infection during each pregnancy, as recommended by health authorities. When an initial prenatal screen is reactive, the Confirmatory HBsAg Test is essential to confirm whether the mother is truly infected. This matters greatly because infants born to HBV-positive mothers have a very high chance of developing chronic HBV infection if preventive steps are not taken promptly.
How to Prepare and What to Expect
Preparing for this test is straightforward. Here is everything you need to know before your appointment.
Do You Need to Fast?
No, fasting is not required before this test. The test detects a viral surface protein, and food intake does not affect the result. If your doctor has requested additional tests alongside this one, check whether any of those tests have fasting requirements.
Practical Tips Before Your Test
A few simple steps can help your appointment go smoothly:
- Stop taking biotin supplements at least 72 hours before sample collection, as biotin can interfere with certain immunoassay-based tests
- Inform your doctor or phlebotomist about any medications, supplements, or recent vaccinations
- Drink adequate water before your test; good hydration makes veins easier to locate
- Wear a top or sleeve that can be easily rolled up to allow access to your inner arm
Step-by-Step Procedure
The blood collection process is quick and straightforward. Here is what happens during your visit:
- A trained phlebotomist will ask you to be seated comfortably and will clean the inner side of your arm with an antiseptic solution.
- An elastic band (tourniquet) is placed around your upper arm to make the vein more visible.
- A fine needle is gently inserted into the vein; you may feel a brief, mild sting.
- A small amount of blood is drawn into a collection tube designed for serum or plasma separation.
- The needle is removed, and light pressure is applied to the site with a cotton swab.
- The sample is labelled and prepared for dispatch to the laboratory, where it is processed within 2 hours of collection.
Factors That Can Affect Accuracy
Certain factors can influence the reliability of the result. Be sure to mention these to your doctor:
- Recent Hepatitis B vaccination (within the past 30 days or longer in some patients, such as those on haemodialysis)
- Cross-reactive antibodies from other infections or immune system conditions
- Severe dehydration, which can affect blood sample quality
- Use of biotin supplements close to the test date
Understanding Your Hepatitis B Surface Antigen (HBsAg) Confirmatory Test Results
Results from the HBsAg confirmation test are reported as confirmed positive or not confirmed (negative). A doctor is best placed to explain what the result means in the context of your overall health.
| Parameter | Result | Interpretation |
|---|---|---|
| HBsAg Confirmatory | Positive (Confirmed) | Active HBV infection is present (acute, chronic, or carrier state) |
| HBsAg Confirmatory | Negative (Not Confirmed) | Initial reactive screen was a false positive; no current HBV infection detected |
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 situations can affect how results are interpreted. Your doctor will account for these when reviewing your report.
A recent hepatitis B vaccination may cause a transient, low-level positive on initial screening. Studies indicate that vaccination-related HBsAg positivity rarely persists beyond 14 days after the vaccine dose; this effect is seen most often in haemodialysis patients. If the screening was done shortly after vaccination, the confirmatory test helps distinguish this from true infection. Additionally, cross-reactive antibodies from other infections or immune disorders may cause a false positive on the initial screen; a not-confirmed result on the confirmatory test in such cases suggests the original reactive result was non-specific.
How to Maintain Healthy Levels
These general wellness tips support liver health and reduce the risk of HBV exposure:
- Ensure you are vaccinated against Hepatitis B if you are not already immune or infected.
- Avoid sharing items that may carry traces of blood, such as needles, razors, or toothbrushes.
- Practise safe sex and discuss HBV prevention options with your healthcare provider.
Lupin Diagnostics Hepatitis B Surface Antigen (HBsAg) Confirmatory Test Price and Home Collection
The Hepatitis B Surface Antigen Confirmation test starts at approximately ₹250, with home sample collection available across cities in India. Indicative city-wise prices are listed below:
| City | Approximate Price (₹) |
|---|---|
| Mumbai | ₹600 |
| Bengaluru | ₹850 |
| Chennai | ₹850 |
| Hyderabad | ₹600 |
| Kolkata | ₹625 |
| Pune | ₹850 |
| Ahmednagar | ₹850 |
Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
- Select the test on the Lupin Diagnostics website.
- Choose your city and preferred time slot.
- Opt for home sample collection by a certified phlebotomist, or visit your nearest Lupin Diagnostics centre.
- Receive your report via email or WhatsApp within the stipulated turnaround time.
Home Collection
Lupin Diagnostics offers home sample collection for the confirmatory HBsAg test across multiple cities in India. All samples are processed in NABL-accredited laboratories by trained technologists, ensuring reliable results. Digital reports are delivered directly to your email or WhatsApp, making the entire process convenient and hassle-free.
Frequently Asked Questions
An initial HBsAg screening can occasionally produce a reactive result that is not a true positive. The Hepatitis B Neutralisation Assay uses a specific neutralising reagent to verify whether real HBsAg is present. This step ensures accurate diagnosis before any further clinical decisions are made.
The screening test checks for the presence of HBsAg using a standard immunoassay. The confirmatory HBsAg test goes a step further by introducing a specific anti-HBs antibody to neutralise any true HBsAg in the sample. A result is confirmed positive only when this neutralisation reduces reactivity by 50% or more compared to the control.
Yes, this is possible. Hepatitis B vaccination can temporarily produce detectable levels of HBsAg in the blood. This transient positivity generally does not last beyond 14 days after vaccination. If your screening was done around the time of a recent vaccine dose, your doctor may recommend the HBs antigen confirmation test to clarify the result.
No, fasting is not needed. This test detects a viral surface protein, and what you eat or drink before the test does not influence the outcome. You can attend your appointment at any time of day.
Results for the Hepatitis B surface antigen confirmation test are usually ready within 1 to 3 days from the time of sample collection, depending on the laboratory.
A confirmed positive result should be reviewed by your doctor along with other relevant markers. Your doctor may request additional tests, such as HBV DNA viral load, HBeAg, and liver function tests, to assess whether the infection is acute or chronic and to evaluate liver health. Do not self-diagnose or delay seeking medical advice.
Yes. When a pregnant woman's initial prenatal HBsAg screen is reactive, the confirmatory HBsAg test is essential to determine whether she is truly infected. Accurate identification of HBV-positive mothers allows healthcare providers to take timely steps to protect the newborn from perinatal transmission of the virus.
Hepatitis B Surface Antigen (HBsAg) Confirmatory Test
