What is tuberculosis, its causes, risk factors, and methods of treatment and prevention

What is tuberculosis? Tuberculosis is a dangerous and highly contagious disease. Tuberculosis usually affects the lungs in particular, and pathogens spread through the airways of the patient and are expelled to those around him through sneezing, coughing and breathing. In this article, tuberculosis will be defined, And a statement of its causes and risk factors for infection, methods of transmission, and methods of diagnosis, treatment and prevention of its occurrence.

What is tuberculosis

Tuberculosis, or tuberculosis, is an infection caused by the bacterium Mycobacterium tuberculosis that usually attacks the lungs with the ability to travel to other parts of the body. Like the brain and spinal cord[1] bones, kidneys, lymph nodes,[2] In 2018, the World Health Organization counted ten million cases of tuberculosis in the world and all age groups distributed as follows: 3.2 million cases in women, 5.7 million in men and 1.1 million in children, but fortunately tuberculosis can be treated and prevented. According to the statistics of this organization, approximately 58 million cases of recovery from the disease were monitored, by following accurate diagnosis and an appropriate treatment approach between the years 2000-2018, and according to studies, this disease will be eliminated by 2030, which is one of the goals of sustainable health development.[3]

Classification of tuberculosis

Symptoms of the disease do not appear in all people infected with tuberculosis bacteria, and therefore tuberculosis infection is divided into two types; They are latent and active [4] In the case of latent tuberculosis, the patient does not show symptoms and the infection is not transmitted to other people. The immune system plays a role in protecting the body in this case and preventing the disease from turning into an active state, but the infection can develop into the active state.

In some cases, and in the active state, the patient suffers from the multiplication of bacteria and the emergence of symptoms with the possibility of transmission to other people, especially if the infection is in the lungs, and studies show that 5-10% of infected people turn their tuberculosis into what is known as the active state, and they are the ones who did not receive any intervention Medical, and about 50% of people with tuberculosis develop symptoms of an active case within 2 to 5 years from the time of infection.[6]

Causes and risk factors for tuberculosis

As mentioned earlier, the main cause of tuberculosis infection is the bacteria Mycobacterium tuberculosis. These bacteria spread through the air and often infect the lungs and some other parts of the body. Although tuberculosis is an infectious disease, it does not spread easily between individuals, so it may require spending a lot of time with the infected person in order to infect others.[7] In most healthy people, the immune system fights and eliminates these bacteria[8].

In this context, it is indicated that the possibility of contracting tuberculosis in some cases is in the weeks following infection with the bacteria before the immune system fights it, while in some cases other symptoms of tuberculosis appear, and the disease can appear after years of exposure to the bacteria, which may be associated with a weakened immune system. For another reason, and in general, people most at risk of contracting tuberculosis are divided into two groups:[9][1]

• People who have recently been exposed to TB bacteria: These include:

• Interacting with a friend, coworker, or family member who has TB
• travel or live in areas affected by tuberculosis; Such as Africa, Eastern Europe, Russia, Asia, Latin America and the Caribbean.
• Doctors, nurses, and staff in hospitals or nursing homes.
• Members of the medical team treating a patient at risk of contracting tuberculosis.
• People who engage in behaviors that increase the spread of TB, such as people who are homeless, people who use drugs, or people who are in prison.

• People with weakened immune systems, including the following:[9][2]

• People infected with the AIDS virus or what is known as the Human Immunodeficiency Virus.
• People with chronic kidney disease who require dialysis to replace lost kidney function. Patients with silicosis, a lung disease.
• Diabetics.
• Head or neck cancer. People who use certain medications that affect the immune system and its ability to fight infection, such as cancer treatments such as chemotherapy, medications given after an organ transplant, and those for lupus or rheumatoid arthritis.
• Infants and young children.[9]
• People whose weight is less than normal.[9]

Tuberculosis transmission methods

In fact, tuberculosis infection is only transmitted by people with active tuberculosis, as the latent disease is not transmitted to others as mentioned earlier, and in general most infected people do not transmit the disease. infection if they have received appropriate treatment for at least two weeks,[10] Usually, the cause of the spread of infection is a long stay with an infected person, and the mechanism of transmission of the disease is indicated. This occurs when a person with pulmonary tuberculosis sneezes, coughs, or speaks, so that the bacteria spread in the air and are transmitted to other people when they are inhaled. It is worth mentioning that the tuberculosis bacteria It is not transferred on household surfaces and items; Such as pottery, crockery, clothing, and personal phones. There is no need to isolate tools from the infected person for fear of spreading the infection to others.[11]

Tuberculosis symptoms

A person is most likely to develop active TB within the first two years of exposure.[12] As previously noted, symptoms are associated with active infection rather than latent infection. It mainly occurs in the lungs and respiratory tract.[2] The symptoms of active TB may be similar to those associated with other diseases, so it is necessary for a person to see a doctor and get tested for TB to confirm or rule out infection. Symptoms of TB include:[13][14]

• A cough that lasts more than three weeks, and may sometimes be accompanied by sputum or blood, which requires a visit to the doctor.
• Loss of appetite and subsequent weight loss.
• Night sweats, fever, and chills
• Certain symptoms related to the functions of organs affected by the bacteria, such as bone pain, which may indicate that the bacteria have spread to the bones.
• Source.[2]
• General tiredness or weakness.
• Usually persistent swelling of the lymph nodes or glands.[10]
• Joint pain.[10]
• confusion.[10]
• convulsive seizures[10]

Diagnosis of tuberculosis

Examinations and tests that are performed contribute to the detection of tuberculosis; Whether latent or active, even though there are no symptoms in latent TB, a test procedure will prove that they are infected. A person should have a diagnosis of TB if they have been in contact with another person who has TB or is at high risk for TB. The individual can also be tested If you stay for a long time in a country infected with tuberculosis or work in an environment where tuberculosis may be present[10] Diagnostic methods for detecting tuberculosis can be explained as follows:[10]

• Taking a medical history and physical examination: The doctor will ask about the symptoms that the person is complaining about and ask about his medical history. He will also perform a physical examination that includes listening to the lungs and checking for swollen lymph nodes.

• Tests for detecting tuberculosis bacteria: These tests include the following:[1]

• Mantoux tuberculin skin examination, in which the doctor injects a small dose of a purified protein derivative under the skin of the forearm, then asks the patient to re-examine it after two to three days to check the site where the dose was injected, and if the person has tuberculosis, the injection site will form a red mass .
• A blood test that releases gamma interferon, which detects the response after an individual’s blood sample is mixed with proteins from tuberculosis bacteria.

• Tests to differentiate between latent and active TB: The previous tests do not determine whether the TB is latent or active, so the doctor will need to do more tests.[10] such as computed tomography,[1] or chest x-ray, or sputum test,[10] In the context of sputum testing, taking a sample of an individual’s sputum and subjecting it to laboratory testing will also help detect drug-resistant strains of tuberculosis bacteria and thus exclude them from the treatment plan and use other effective drugs to treat the disease. These tests usually last one to two months. To complete its results and obtain the correct diagnosis of the disease.[16]
• Tests that aim to detect the spread of bacteria to other parts of the body: These tests include:[17]

• Computed tomography, magnetic resonance imaging, or ultrasound of affected organs.
• Blood and urine tests.
• Biopsy, which involves taking a sample of infected tissue or organic fluid and examining it in a laboratory for TB bacteria.
• Lumbar puncture, which involves taking a small sample of the cerebrospinal fluid surrounding the brain and spinal cord if infection of the central nervous system with tuberculosis bacteria is suspected.

Tuberculosis treatment

In general both cases require tuberculosis; Latent and active anti-tuberculosis therapy[10] Treatment of tuberculosis takes longer than other types of bacterial infections, and drugs are the cornerstone of treatment, so the doctor prescribes one or two drugs to the patient in cases of latent tuberculosis, and cases of active tuberculosis require the patient to adhere to the prescribed antibiotics for a period of not less than 6 to 9 months, and it depends The type of antibiotic and the duration of treatment depends on several factors, including: the patient’s age, general physical health, the site of infection in the body, the body’s resistance to drugs, and in general, the presence of resistance to a certain strain of bacteria requires the use of a number of specific drugs to treat active tuberculosis in particular, and the following is a statement The most important drugs used in the treatment of tuberculosis:

• The most common medications: These include: pyrazinamide, ethambutol, isoniazid or rifampicin.
• If the patient’s body is resistant to the usual anti-tuberculosis drugs: in these cases fluoroquinolone antibiotics are given with other injectable drugs such as capreomycin or amikacin for 20 to 30 months, additional drugs may also be prescribed to the treatment plan. such as bedaquiline and linezolid.

The patient begins to improve and becomes non-infectious within weeks of starting treatment, which creates a desire in the patient to stop the medications, but it is absolutely necessary for the patient to complete the treatment completely and take the medications prescribed by the doctor, such as stopping the medication prematurely or missing doses at specific times This can lead to bacterial re-growth and the possibility of drug resistance, which in itself will make TB more dangerous and more difficult to treat.[16].

It should be noted that the treatment used for cases of tuberculosis that affects organs other than the lungs is to use the same group of drugs used in the treatment of pulmonary tuberculosis. Swelling of the tissues of the affected organs, so that they are taken for several weeks at the same time. Of antibiotics, in addition, following this guide according to the doctor’s instructions will reduce the occurrence of side effects, and in general it can be said that the side effects of anti-tuberculosis drugs are not common but serious if they do occur, and all anti-tuberculosis drugs can affect on the liver, so you should tell your doctor if any of the following symptoms appear:[18]

• Anorexia.
• jaundice
• Dark colored urine.
• Nausea or vomiting.
• A fever that lasts three or more days without an identifiable cause.

Tuberculosis prevention

Although tuberculosis is one of the world’s leading killers, it can be treated and prevented by reducing poverty, improving nutrition, post-treatment treatment, and immunization.[20] Prevention requires isolation of infected people until they are not contagious, and they can be offered to patients who have a preventive treatment plan after diagnosis, and prevention also includes giving BCG vaccine to young children who travel to countries where tuberculosis is common, since vaccination may vary depending on the approved vaccination schedule by the state,[11] To prevent tuberculosis, the following tips should be followed:[12]

• Maintain good personal and environmental hygiene.
• Covering the mouth and nose when sneezing or coughing, and removing secretions from the mouth and nose properly.
• Wash your hands thoroughly at all times, especially if they are dirty from exposure to respiratory secretions such as sneezing.
• Adopt a healthy lifestyle that includes a balanced diet, exercise and adequate rest.
• Take the tuberculosis vaccine according to the immunization schedule. Seek treatment immediately when symptoms are similar to tuberculosis, especially a cough that has lasted for more than a month.

In conclusion, this article answered the question posed, what is tuberculosis?, and explained its causes, risk factors, transmission methods, and methods of diagnosis, treatment, and prevention.