Tuberculosis is a dangerous infectious disease that affects the internal organs of humans and animals. The lungs are mainly affected, but there is also tuberculosis of the kidneys, bladder, bones and other organs and systems.
Despite modern methods of diagnosis and treatment of this disease, the statistics of the spread of tuberculosis remains sad. This is especially true for Russia. According to some reports, Russians are at risk of infection ten times more than residents of developed countries. In addition, tuberculosis occurs even in members of we althy families with a high standard of living. Therefore, it is so important to have regular medical examinations and, if necessary, take a sputum test for tuberculosis.
Tuberculosis etiology
The causative agent of this dangerous disease is Koch's wand. itmycobacterium (lat. Mycobacterium tuberculosis), which is transmitted by airborne droplets. The bacterium belongs to the class of fungi, has a small size and a dense shell, which allows it to survive in the environment and makes the microorganism very tenacious. This explains the prevalence of the disease - they can be infected during normal conversation with the patient, especially if he sneezes or coughs at this time.
The insidiousness of the disease lies in the fact that in most cases it is asymptomatic. According to statistics, only one in ten cases becomes active.
What are the first signs of TB?
The first warning signs will be:
- Prolonged lingering cough.
- The appearance of traces of pus and blood in the sputum.
- Subfebrile temperature values.
- Weight loss.
- Lack of appetite.
- Permanent feeling of tiredness.
If you have one or more signs, you must undergo an examination without fail. Especially if there is a cough with a suspicious secretion. It is necessary to undergo a fluorography, which every Russian must do once a year.
In the event that any formation is found on the image, the diameter of which will exceed one centimeter, the person must be sent for additional tests.
What does TB sputum look like?
In the initial stages, the patient has only a silent secret. It is usually white in color due to its high protein content.
In later stages, streaks of blood and pus appear in the mucus. At this stage, the color of sputum can be yellow, green, or even red. It all depends on the ratio of blood and pus in it. A photo of sputum with tuberculosis of the last stages is presented below.
In the initial stages, sputum is usually viscous and contains a lot of mucus. As the disease develops, a large amount of moisture appears in it, which makes it more liquid. Based on this, we can conclude that sputum with tuberculosis can be of very different consistency.
Tuberculosis Diagnosis
In medical diagnostics, there are several ways to determine the disease in patients. The most common of these is sputum culture.
Sputum test for tuberculosis is carried out in two stages:
- External examination of sputum (macroscopy).
- Bacteriological culture (microscopy).
Sputum collection for tuberculosis
How to properly collect biological material? In a person with tuberculosis, sputum contains a huge amount of Koch's sticks. When examining mucous secretions, you can detect the pathogen and make a conclusion about the presence or absence of the disease in the patient.
However, for accurate and reliable results, the patient needs to properly prepare for the test and collect sputum for mycobacteriatuberculosis in accordance with all regulations:
- It is extremely important to carry out the analysis in the morning, as a large amount of secretion accumulates in the upper respiratory tract during the night. This will help him to easily move away from the walls of the bronchi in the morning.
- The patient should delay breakfast until the biomaterial is collected. The fact is that eating can change the composition of sputum in tuberculosis, as well as make it difficult to discharge.
- Some doctors advise patients to take an expectorant beforehand to facilitate the passage of the biomaterial.
- Pay attention to the fact that it is sputum that needs to be collected, not saliva.
- Before taking the test, brush your mouth with toothpaste, then rinse your mouth with boiled water. This will help prevent any foreign bacteria from entering the sputum. Brush your teeth with a toothbrush with a hardness not higher than medium. This will reduce the risk of injury to the gums and prevent blood from entering the sputum. In tuberculosis, it can be present in the biological material only in the later stages of the disease.
- The biomaterial is rented in a special container, which can be purchased at any pharmacy. The container is sterile and has a screw cap that must be opened immediately before sputum collection. After collection, the container is immediately closed.
- For a more productive expectoration, the patient should take three deep breaths, and then cough effectively.
- The amount of material required for a successful analysis is usuallycan be obtained in two or three expectorations.
- It is very important to donate sputum in a well ventilated area. The entrance to it must be marked with a special sign, meaning that outsiders are strictly forbidden to enter here. Doctors must have some level of protection in the form of a mask or respirator.
Analysis
Even at the initial stages of the disease, the sputum of a patient with tuberculosis outwardly differs from the norm. It acquires a grayish or greenish color, it contains pieces of mucus or pus. In the first stages, the presence of blood is not necessary at all, it is more typical for the cavernous stage, when the integrity of the vessels is already broken.
When examined under a microscope, oval or slightly curved rods are found. The length of which is from 1 to 10 microns, and the diameter is from 0.2 to 0.6. Mycobacterium tuberculosis in sputum looks like this: pay attention to the photo below.
In addition, with the help of a microscope, you can detect calcium s alts, cholesterol formation, elastic fibers. All these are products of the breakdown of lung cells. Their detection in the analysis suggests that the process of organ damage has already begun.
Then bacteriological culture of sputum for tuberculosis is performed:
- Laboratory assistant inoculates sputum on a nutrient medium placed in a Petri dish.
- At the second stage of work, the preparation is stained using the Ziehl-Nelson method. This method assumesclarification with a carbolic solution of fuchsin. After that, the preparation is affected by a number of chemicals (hydrochloric alcohol, sulfuric acid).
- The next step is to stain the preparation with methylene blue.
- As a result of this, the entire preparation turns blue, and the tuberculosis bacilli do not stain. Therefore, in case of infection, they will be very clearly visible. If the entire preparation is blue, then this will mean that the patient does not have tuberculosis.
How many times is this analysis required?
It is worth considering that the first negative result is not a guarantee of he alth. The fact is that, although this method is very sensitive, it guarantees the reliability of the result only if there are at least 100 thousand mycobacteria in 1 ml of the sample. Therefore, if there is a suspicion of tuberculosis in a patient, he needs to pass sputum two more times with an interval of 1 month.
The sensitivity of the first analysis is 80%, while the second and third are 90% and 97% respectively.
If all three analyzes are negative, it is safe to conclude that the patient is he althy. A sputum test for tuberculosis takes about two to five weeks. This is how long it takes to identify pathogens in sputum.
Bronchoscopy. Another method for diagnosing tuberculosis
However, bacteriological analysis is not always possible. There are cases when expectoration of the biomaterial is ineffective. What to do in such situations? ATIn medical diagnostics, there is a bronchoscopy method, when a specialist takes samples of bronchopulmonary tissue with the help of an apparatus.
This procedure is done after local anesthesia is given to the patient. If the patient is a child who cannot lie still during the procedure, general anesthesia will be required. Bronchoscopy lasts several minutes, during which the specialist introduces a small manipulator through the nasal or oral cavity. At the end of the device there is a probe that can capture the right amount of sample.
One of the advantages of this method is the ability to remove pathological secretions from the patient's bronchi.
PCR. The most modern method for diagnosing tuberculosis
One of the most modern methods of diagnosing tuberculosis is a polymer chain reaction, which consists in isolating a DNA fragment of mycobacteria from the biomaterial, which allows us to conclude that the patient is infected.
Its main advantage is expressiveness. The result of the analysis is ready in 3-5 hours, which means that there is no need to wait several weeks, as is the case with bacteriological culture. The advantages of the method also include:
- High reliability of the results.
- Low amount of material needed for analysis.
- Ability to analyze any biological material.
The disadvantages of the method are:
- Its high cost.
- Assay failure after anti-tuberculosis treatment. The fact is that a recovered person has dead mycobacteria in the body. In this case, PCR will still give a positive result, despite the fact that the person is already he althy.
Conclusion
In the modern world, tuberculosis is no longer considered a fatal disease, as it was until recently. This disease is treated, and quite successfully. The main thing is to detect the pathogen in your body in time. To do this, in medical diagnostics, there are several effective ways to detect Mycobacterium tuberculosis: fluorography, bacteriological culture of sputum for tuberculosis, bronchoscopy, PCR, and others. Do not neglect such an opportunity. You need to regularly undergo medical examinations, monitor your general well-being, try to improve your standard of living.
