MTB Susceptibility – Ethionamide Test: Booking, Price, and Results
About MTB Susceptibility – Ethionamide Test: Booking, Price, and Results
| Field | Value |
|---|---|
| Also Known As | TB Drug Susceptibility Test – Ethionamide, AFB/TB Susceptibility Ethionamide, MTB DST Ethionamide, Second-line TB Drug Sensitivity Test |
| Sample Type | Sputum, BAL, CSF, pus, urine, tissue, swab and other body fluids or specimens where TB infection is suspected may also be performed on a pure MTB culture |
| Fasting Required | No fasting required |
| Report Time | 29 days |
| Recommended For | Adults and children with confirmed or suspected drug-resistant tuberculosis |
| Price | Starting at ₹2,200 |
What Is an MTB Susceptibility – Ethionamide Test?
The MTB Susceptibility – Ethionamide test checks whether the tuberculosis-causing bacterium, Mycobacterium tuberculosis (MTB), is sensitive or resistant to the antibiotic ethionamide. Ethionamide is a second-line drug used when first-line TB medications are no longer effective. The test is ordered for patients with confirmed or suspected drug-resistant TB and can be performed on a wide range of clinical specimens such as sputum, body fluids or tissue. It is also known as the TB Drug Susceptibility Test – Ethionamide or MTB DST Ethionamide.
What Does an MTB Susceptibility – Ethionamide Test Measure?
This test measures whether the MTB bacteria present in a patient's sample will respond to ethionamide. The result is reported as either 'Sensitive' or 'Resistant'.
| Result | Meaning |
|---|---|
| Sensitive (S) | The TB bacteria respond to ethionamide; the drug is likely to be effective as part of treatment |
| Resistant (R) | The TB bacteria do not respond to ethionamide; alternative drugs will need to be considered |
The test uses an automated method, with susceptibility assessed at the critical concentration for ethionamide as defined by standard laboratory guidelines.
Why Is an MTB Susceptibility – Ethionamide Test Done?
This test is typically ordered after a TB diagnosis has been confirmed and there is a concern that the bacteria may not respond to standard drugs. A doctor may request it in a range of clinical situations.
Common Symptoms That May Require This Test
The following symptoms may prompt a doctor to investigate for drug-resistant TB and request this test.
- Persistent cough lasting more than three weeks, sometimes producing mucus or blood
- Unexplained weight loss
- Prolonged fever
- Night sweats
- Chest pain or discomfort
- Unusual fatigue or weakness
- Poor response to first-line TB treatment
Conditions This Test Can Help Detect
This test is used to identify resistance patterns in TB infection. It can support the diagnosis of the following conditions.
- Multidrug-resistant TB (MDR-TB), where the bacteria are resistant to at least isoniazid and rifampicin
- Extensively drug-resistant TB (XDR-TB), a more difficult-to-treat form of the disease
- Second-line drug resistance, helping doctors select the most appropriate treatment regimen
MTB Susceptibility – Ethionamide Test for Chronic Disease Monitoring
For patients already receiving treatment for drug-resistant TB, this test may be repeated to monitor the bacteria's response to the current regimen. For patients already receiving treatment for drug-resistant TB, this test may be repeated to assess how the bacteria respond to therapy. India's TB programme includes ethionamide in second-line regimens used during both intensive and continuation phases of treatment, making periodic susceptibility testing relevant for monitoring treatment progress. Repeat susceptibility testing helps detect any emerging resistance and allows the treating doctor to adjust the treatment plan accordingly.
How to Prepare and What to Expect
Sample collection for this test must follow strict sterile procedures. Your doctor or a trained healthcare professional will guide you through the process based on the specimen type required.
Do You Need to Fast?
No fasting is required for the MTB Susceptibility – Ethionamide test. You can eat and drink normally before your appointment.
Practical Tips Before Your Test
These steps will help ensure that your sample is suitable for testing.
- Bring a detailed clinical history, including your symptoms, previous test results and any treatment you are currently receiving, as this is required for the test
- Provide your complete address and a working mobile number at the time of booking
- If a sputum sample is needed, rinse your mouth thoroughly with plain water before collection; do not use mouthwash
- Collect sputum early in the morning, when production is typically highest
- Inform your doctor about all current medications and any existing health conditions
- Wear comfortable clothing if a blood draw or additional tests are needed alongside this one
- Follow any additional instructions given by your healthcare provider regarding sample collection
Step-by-Step Procedure
The collection method depends on the type of sample your doctor has requested. The steps below describe the general process.
- Your doctor will advise which specimen is needed: sputum, BAL, CSF, pus, urine, tissue, swab or another body fluid, based on your clinical presentation and the site of suspected TB infection.
- The sample is collected under sterile conditions to prevent contamination.
- For sputum, you will be asked to take a deep breath and cough into a sterile container.
- For other specimen types (such as CSF, pleural fluid or tissue), a trained healthcare professional will collect the sample at a clinical facility.
- The labelled specimen is stored at refrigerated temperature (2 to 8°C) and transported to the NABL-accredited Lupin Diagnostics laboratory.
- In the lab, the sample is processed using an automated method, and the MTB bacteria are tested against ethionamide at the defined critical concentration.
- Results are reviewed, and the report is made available within 29 days.
Factors That Can Affect Accuracy
Several factors may influence the reliability of this test's results.
- Poor sample quality or insufficient volume of the specimen
- Contamination during sample collection
- The thermolabile (heat-sensitive) nature of ethionamide, which makes accurate testing more challenging
- Current medications or other health conditions present at the time of testing
- The testing method used, as the difference between susceptible and resistant concentrations for ethionamide is narrow
Understanding Your MTB Susceptibility – Ethionamide Test Results
Results from the MTB Susceptibility – Ethionamide test are interpreted by your treating doctor alongside your full clinical picture. The table below explains what each result generally means.
| Parameter | Result | Interpretation |
|---|---|---|
| Ethionamide Susceptibility | Sensitive (S) | MTB bacteria are likely to respond to ethionamide treatment |
| Ethionamide Susceptibility | Resistant (R) | MTB bacteria are unlikely to respond to ethionamide; alternative drugs may be needed |
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 may make this test's results harder to interpret.
- Due to the narrow difference between susceptible and resistant concentrations, there can sometimes be poor agreement between laboratory findings and clinical outcomes.
- When testing is performed on solid culture medium, the minimum inhibitory concentration for ethionamide is very close to its therapeutic level, which increases the chance of borderline readings.
- Current medications and existing health conditions may also influence results; always share this information with your doctor.
How to Maintain Healthy Levels
These are general wellness tips for patients being investigated or treated for TB.
- Complete the full prescribed course of any anti-TB medication without interruption to reduce the risk of drug resistance developing.
- Support your immune system with adequate nutrition, rest and hydration throughout the treatment period.
- Follow all infection control guidance provided by your healthcare team to protect those around you.
Lupin Diagnostics MTB Susceptibility – Ethionamide Test Price
The MTB Susceptibility – Ethionamide test is priced starting at ₹2,200 at Lupin Diagnostics. This test requires a visit to a Lupin Diagnostics centre or a doctor-directed sample collection facility; home collection is not available. The city-wise price breakdown is provided below.
| City | Approximate Price (₹) |
|---|---|
| BHOPAL | 2200 |
| CHENNAI | 2200 |
| HYDERABAD | 2200 |
| KOLKATA | 2200 |
| NAVI MUMBAI | 2200 |
| PUNE | 2200 |
Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
MTB Susceptibility – Ethionamide test online booking is available through the Lupin Diagnostics website. Follow these steps.
- 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
This is a laboratory test that checks whether the tuberculosis-causing bacterium, Mycobacterium tuberculosis, is sensitive or resistant to the antibiotic ethionamide. The result helps your doctor decide whether ethionamide can be included in your treatment plan. It is relevant for patients with drug-resistant TB.
This test is typically ordered after a TB diagnosis has been confirmed and drug resistance is suspected. It may also be repeated during treatment to check whether the bacteria are still responding to the current drug regimen.
The MTB Susceptibility – Ethionamide test report is available within 29 days. This is because growing and testing the bacteria accurately takes time; rushing the process can affect the reliability of results.
A wide range of specimens can be used, including sputum, BAL, CSF, pus, urine, tissue, swabs and other body fluids. A pure MTB culture may also be submitted. Your doctor will advise which sample is appropriate based on the site of infection.
No fasting or special preparation is required. If a sputum sample is required, rinse your mouth with plain water before collection and try to collect the sample in the morning. Bring your clinical history and provide your full address and contact number when booking.
Yes. Children can undergo this test if it is recommended by their doctor. The MTB Susceptibility – Ethionamide test procedure and specimen collection approach will be adapted to suit the child's age and clinical condition.
A resistant result means the TB bacteria in your sample are unlikely to respond to ethionamide. You should consult a doctor specialising in infectious diseases or pulmonology. They will review your full results and recommend suitable alternative second-line drugs as part of a revised treatment plan.
Yes, this test can be scheduled every day of the week at Lupin Diagnostics centres. Contact your nearest centre to confirm timings and ensure your sample type is accepted at that location.
MTB Susceptibility – Ethionamide Test: Booking, Price, and Results
