Coombs Test, Indirect Test: Booking, Price, and Results
About Coombs Test, Indirect Test: Booking, Price, and Results
| Field | Value |
|---|---|
| Also Known As | Indirect Antiglobulin Test (IAT), Antibody Screen, Red Blood Cell Antibody Screen |
| Sample Type | Serum |
| Fasting Required | No fasting required |
| Report Time | 1 Day |
| Recommended For | All adults, especially pregnant women, pre-transfusion patients, and individuals with suspected blood disorders |
| Price | Starting at ₹500 |
What is a Coombs Test, Indirect Test?
The Coombs Test, Indirect Test is a blood test that detects antibodies circulating freely in the bloodstream that could attach to and destroy red blood cells. It is also known as the Indirect Antiglobulin Test (IAT) or Antibody Screen. Doctors typically order this test before a blood transfusion or as part of routine prenatal care. A small serum sample, drawn from a vein in your arm, is used for the analysis.
What Does a Coombs Test, Indirect Test Measure?
This test looks for specific immune proteins (IgG antibodies) floating freely in the liquid portion of your blood. These antibodies have the potential to react against red blood cells that the body treats as foreign.
| Component | What It Assesses |
|---|---|
| Free-floating IgG antibodies | Antibodies in your serum that could bind to and damage red blood cells |
| Plasma antibody presence | Whether your blood contains antibodies not yet attached to any red blood cells |
| Agglutination response | Whether those antibodies cause red blood cells to clump together when tested in the laboratory |
Why is a Coombs Test, Indirect Test Done?
This test is ordered in several clinical situations, from routine pregnancy screening to pre-transfusion checks.
Common Symptoms That May Require This Test
Your doctor may request this test if you experience any of the following:
- Unexplained fatigue or persistent weakness
- Pale skin or pallor
- Shortness of breath without a clear cause
- Jaundice, which is the yellowing of the skin or eyes
- Dark or tea-coloured urine
- Unexplained anaemia (low red blood cell count)
- Unusual bruising or prolonged bleeding
Conditions This Test Can Help Detect
This test can help identify several blood-related conditions, including:
- Haemolytic disease of the newborn (HDN), where maternal antibodies cross the placenta and attack foetal red blood cells
- Detects whether a patient's blood is compatible with donor blood to help prevent transfusion reactions.
- Autoimmune haemolytic anaemia, where the immune system mistakenly targets the body's own red blood cells
- Prior sensitisation from previous transfusions or pregnancies
Coombs Test, Indirect Test During Pregnancy
The Indirect Antiglobulin Test is a routine part of prenatal care, particularly for women with Rh-negative blood. If an Rh-negative mother carries an Rh-positive foetus, there is a risk of Rh incompatibility, which can lead to haemolytic disease of the newborn. Pregnant women typically receive this test at their first prenatal visit and again around 28 weeks of pregnancy.
How to Prepare and What to Expect
Preparation for this test is simple, and the procedure is quick.
Do You Need to Fast?
No fasting is required before the Coombs Test, Indirect Test. You can eat and drink normally before your appointment. If other tests have been ordered alongside this one, ask your doctor whether those require fasting.
Practical Tips Before Your Test
Keep the following in mind before your sample collection:
- Inform your doctor about all medications and supplements you are currently taking, as some can affect results
- Drink plenty of water before your appointment to stay hydrated
- Wear clothing with loose or short sleeves for easy access to your arm
- Let the phlebotomist know if you have a latex allergy
Step-by-Step Procedure
Here is what happens during the Coombs Test, Indirect Test procedure:
- A trained phlebotomist cleans the skin on your arm and inserts a small needle into a vein to collect a blood sample.
- A small amount of blood is drawn into a collection tube and labelled with your details.
- In the laboratory, the serum (clear liquid portion of blood) is separated from the red blood cells.
- The serum is mixed with donor red blood cells of known antigen types and incubated to allow any antibodies to bind.
- An antiglobulin reagent (Coombs serum) is added to the mixture.
- The sample is examined for agglutination (clumping). Results are reported as positive, negative, or equivocal, and the sample is dispatched for final reporting.
Factors That Can Affect Accuracy
Several factors may influence the reliability of your results:
- Certain medications, including cephalosporin antibiotics, penicillins, methyldopa, and quinidine
- A recent blood transfusion
- Antiphospholipid antibodies in the blood
- Improper sample handling or storage
- Use of an older or degraded sample
Understanding Your Coombs Test, Indirect Test Results
Results from this test are straightforward to interpret, though your doctor will always review them alongside your medical history.
| Parameter | Normal Result | Interpretation |
|---|---|---|
| Indirect Coombs Test | Negative (no agglutination seen) | No antibodies against red blood cells were 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.
A negative result means no circulating antibodies were found that could react against red blood cells. A positive result means such antibodies are present, and further evaluation is needed.
Results During Special Conditions
Certain situations can cause results that do not reflect true immune activity.
Cephalosporin antibiotics produce a positive result in roughly 4% of treated patients through a non-immunological mechanism, without any actual destruction of red blood cells occurring.
Daratumumab, a medication used to treat multiple myeloma, can also cause a false-positive Indirect Antiglobulin Test result by interfering with serological testing.
In patients hospitalised with COVID-19, a positive result appears in approximately 20% of cases without evidence of actual haemolysis.
Antiphospholipid antibodies can similarly produce a false-positive reading.
How to Maintain Healthy Levels
These general wellness steps can support your overall blood health:
- Attend all scheduled prenatal check-ups if you are pregnant, particularly if you have Rh-negative blood
- Always inform healthcare providers of your full transfusion and pregnancy history before any procedure
- Discuss any known autoimmune conditions openly with your doctor so they can factor this into your care
Lupin Diagnostics Coombs Test, Indirect Test Price and Home Collection
The Coombs Test, Indirect Test cost at Lupin Diagnostics starts at ₹500, and home collection is available across multiple cities. Prices may vary by location.
| City | Approximate Price (₹) |
|---|---|
| BHOPAL | 500 |
| CHENNAI | 590 |
| HYDERABAD | 500 |
| KOLKATA | 500 |
| NAVI MUMBAI | 500 |
| PUNE | 500 |
Disclaimer: Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
Here is how to book your Coombs Test, Indirect Test online booking:
- 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
The Coombs Test, Indirect Test home collection service is available across cities, with a certified phlebotomist visiting your home to collect the sample. All samples are processed in NABL-accredited laboratories, ensuring quality and accuracy. Your digital report is delivered conveniently via email or WhatsApp.
Frequently Asked Questions
The direct Coombs test checks whether antibodies are already attached to your red blood cells, and is commonly used to diagnose autoimmune haemolytic anaemia. The Indirect Antiglobulin Test checks for antibodies floating freely in your bloodstream that have not yet attached to red blood cells. The indirect version is mainly used for pre-transfusion screening and prenatal testing.
No fasting is needed. You can eat and drink as normal before your appointment. Simply inform your doctor about any medications you are taking ahead of your test.
Pregnant women with Rh-negative blood are at risk of Rh incompatibility if they carry an Rh-positive baby. The Coombs Test, Indirect Test helps detect circulating antibodies early, allowing doctors to take steps that protect the foetus from haemolytic disease of the newborn.
A positive result indicates that your blood contains antibodies capable of attacking red blood cells that your body treats as foreign. This does not always mean a serious condition is present. Your doctor will request further tests to understand the cause and significance of the result.
Yes, some medications can cause a false-positive result without any actual destruction of red blood cells. These include certain antibiotics and some drugs used in cancer treatment. Always give your doctor or the laboratory a full list of medications you are currently taking before the test.
Pregnant women typically get this test at their first prenatal visit and again at around 28 weeks of pregnancy. Women with Rh-negative blood or a history of previous pregnancies or transfusions may need it more frequently, as advised by their obstetrician.
The test involves a routine blood draw. A small needle is inserted into a vein in your arm, and you may feel a brief, mild pinch at the moment of insertion. The discomfort passes quickly, and the entire sample collection takes only a few minutes.
Coombs Test, Indirect Test: Booking, Price, and Results
