This is an automatically translated article.
Tuberculosis is caused by the bacteria Mycobacterium tuberculosis and usually affects the lungs. Although TB is curable and preventable, the ability to spread the disease is very strong from person to person through the air when someone with TB coughs, sneezes, or spits. Therefore, taking sputum is also a means of diagnosing a person with tuberculosis.
1. What is tuberculosis?
Tuberculosis is an infectious disease caused by the bacterium Mycobacterium tuberculosis. The disease usually affects mainly the lungs, sometimes spreads to other organs, and the severity is often severe.
TB bacteria are spread from person to person through tiny droplets released into the air through coughing and sneezing. When a normal person gets infected, on the basis of weakened resistance, germs will multiply and cause disease. The damage to organs from TB is irreversible. In the lungs, even though the treatment controls and destroys the bacteria, the lung parenchyma and pleura can still have long-term sequelae, causing the patient to have difficulty breathing, fatigue, cough, and sputum.
In countries that are not endemic areas, migrants are always screened for TB. In contrast, in an endemic setting, any pulmonary involvement or respiratory symptoms, the diagnosis of pulmonary tuberculosis should be confirmed or excluded.
Once diagnosed with TB, the treatment needs to be strictly adhered to the regimen and periodically checked. When this is done, TB control will be successful as well as reducing the risk of transmission to family members and the community.
Bệnh lao lây lan từ người này sang người khác qua những giọt bắn trong không khí
2. What is a sputum test to diagnose tuberculosis?
Sputum or phlegm is mucus that a person excretes by coughing up from deep inside the lungs and leading out through the bronchial tubes. This is mucus, sticky, clear or opaque and white, blue, yellow... Sputum is not saliva because saliva is a liquid, excreted from the oral cavity and is always white and clear. It is important to distinguish these two concepts because of their significant influence on test results.
Because TB bacteria often cause disease in the lungs, testing sputum for the presence of TB bacteria is the best way to determine if a person has TB.
At the same time, on a person who is taking medicine for tuberculosis, the sputum test is also a way to monitor the effect of the drug, whether it is resistant or not. This will help the doctor adjust the regimen accordingly and continue to assess response.
When a sputum test diagnoses TB, a person needs to have a lot of samples collected. Collecting multiple samples can improve the accuracy of test results while a single negative sample cannot rule out disease. Sputum samples can be collected multiple times on the same day or each sample on several separate days. In general, the larger the number of samples tested, the higher the chance of finding the presence of TB germs.
Xét nghiệm đờm có vai trò quan trọng trong việc chẩn đoán bệnh lao
3. Instructions on how to take sputum to diagnose tuberculosis
The way sputum is taken will affect the value of the sputum test to diagnose tuberculosis, affect the diagnosis as well as the treatment and prognosis for the patient.
Therefore, to improve the accuracy of the test, before taking samples, patients need to be instructed on how to take sputum to diagnose TB correctly and effectively. Accordingly, to collect sputum, follow these steps:
Collecting sputum should be done early in the morning, right after waking up. Do not eat, drink, smoke, brush your teeth or use mouthwash right before the time you need to collect sputum. Choose a well-ventilated area to collect the sputum sample. If you can't get out of bed, open a window and keep the room cool. There are no people near the sampling area, especially children, the elderly or people with chronic diseases, weakened because it is easy to cause infection. Verify that personal information such as name, gender and address are correct on the specimen collection vial. Open the cap of the sample vial and do not touch the inside of the vial or the inside of the cap. Take a deep breath in until your chest expands as much as possible. Try to hold your breath to keep the airflow in your chest for a few seconds. Exhale as slowly as possible. Repeat the process of taking a deep breath and coughing vigorously until phlegm appears in the mouth. Spit the sputum into the sample vial. If the amount of sputum is too small, it is necessary to repeat the above steps so that the amount of sputum collected is enough to cover the bottom of the vial. Tighten the sample vial cap so that the specimen does not leak out. Can be wrapped in a nylon bag. Write the date and time of sputum collection on the label of the sample bag. Finally, wash your hands.
Đờm sau khi lấy sẽ được đưa về phòng xét nghiệm
Samples collected in the following mornings do the same.
The sample vial will be delivered to the laboratory in a sealed container the same morning and on the same day as soon as possible. If this is not possible, the sample vials should be stored in a suitable environment, both to avoid the spread of pathogens but not to weaken them. However, after the final sputum sample is taken, all samples are also taken for testing as soon as possible.
Laboratory technicians will perform a smear and culture for TB germs over a certain period of time. As such, the results are not immediately available, but are usually returned to the doctor who orders a sputum test to diagnose tuberculosis within a few days. Thanks to this, the doctor can make a diagnosis as well as evaluate and monitor treatment.
In summary, the sputum test for TB diagnosis is a classic, simple and still valid today. The presence of TB bacteria in sputum helps doctors diagnose and control this dangerous infectious disease in the community.
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