Culture MTB, automated Test
About Culture MTB:
Mycobacterium Tuberculosis (MTB) is a bacterium (Pl. Bacteria) that causes Tuberculosis (TB). This mycobacterium is constantly changing in order to survive within the host. It primarily affects the lungs, but it can also affect other organs such as the brain, spinal cord, and kidneys. TB is a contagious bacterial infection that is usually spread through air.
Culture MTB is a test that helps in the diagnosis of TB in individuals as well as assesses how well anti-tubercular medications work as a treatment. In contrast to the results from conventional culture tests and drug sensitivity, culture MTB is useful in the rapid detection of TB in individuals who need immediate treatment.
Symptoms of Tuberculosis
Symptoms of active TB involve
Cough
Coughing up blood or mucus
Chest pain
Pain while breathing
Fever
Chills
Night sweats
Weight loss
Loss of appetite
Fatigue
When and who should get tested?
This test is indicated if you
Are experiencing active TB symptoms
Have had a positive screening test for TB
Have had TB in the past and now have a relapse/re-infection
Need a change in anti-tubercular therapy
Are taking drug resistance surveillance
Test preparation:
Your healthcare provider will instruct you to collect your sputum sample in a sterile container. This sputum sample is then put into a small culture dish with a substance added to it that helps in bacterial growth. This dish is then kept in a special environment to encourage the growth of bacteria and is daily examined under the microscope to check how much bacterial growth has occurred.
In certain cases, a healthcare professional will obtain the sputum through aspiration or biopsy if the individual is experiencing difficulty in collecting sputum on their own.
This culture is also helpful in finding drug resistance, also known as drug susceptibility testing. It means testing anti-tubercular drugs to find if a person is resistant to these drugs and if so which ones.
Interpretation of results
The results for Culture MTB testing are generally given in relation to the drug susceptibility testing. These are expressed as detected, detected and susceptible, indeterminate and not detected.
|
Bacterial infection |
Drug susceptibility |
Results/Indication |
|
Positive |
Resistant |
Detected |
|
Positive |
Susceptible/not resistant |
Detected and susceptible |
|
Positive |
Unclear |
Indeterminate |
|
Negative |
- |
Not detected |
· If the test findings indicate detected, it means bacteria was found in your specimen and was resistant to the Anti-tubercular drugs.
· If the test findings indicate detected and susceptible, it means bacteria was found in your specimen and was not resistant to anti-tubercular drugs.
· If the test findings indicate indeterminate, it means bacteria was found in your sample but it is unclear whether it was resistant to anti-tubercular drugs.
· If the test findings indicate not detected, it means no bacteria was found in your sample. Therefore, no need to test for drug susceptibility.
FAQs
What is the turnaround time (TAT) for Culture MTB, automated?
The automated culture MTB results are available 5-6 weeks after the sample collection. The specimens/samples are kept in special conditions to encourage the growth of bacteria, which takes time. When bacterial growth is detected, it is tested for drug resistance.
Are there any limitations to culture MTB, automated test?
There are a few limitations to culture MTB, automated tests. These include:
· This procedure necessitates the use of specialized equipment and laboratory facilities. Such equipment is not available in every laboratory.
· Because Mycobacterium tuberculosis grows slowly, testing and diagnosing TB via culture takes time.
However, Lupin Diagnostics has all the laboratory equipment that is required for culture MTB, automated.
My anti-tubercular medications have had no positive effects on me. Should I take the Culture MTB, automated test?
If you are experiencing no improvement in your condition despite taking anti-tubercular drugs, it is recommended that you undergo this test to determine whether the bacteria has developed resistance to the drugs you are taking or if you require an increase in the dose.
Are there any risks to culture MTB, automated test?
The risk is usually determined by the procedure used to collect your specimen. If your sputum sample is collected with no external involvement (i.e., if you can cough up enough sputum on your own) there are no risks other than feeling a little uncomfortable for a few minutes. However, if the sample was obtained through aspiration or biopsy, you may experience pain and discomfort that lasts for a few hours to a couple of days.
Which culture media is used for the detection of tuberculosis bacteria?
In general, Agar-based or egg-based media with green malachite and Middlebrook broths, or even solid media, are considered the gold standard for tuberculosis bacteria isolation, culture, and definite diagnosis.
Related tests
Tests At Lupin Diagnostics