Tuberculosis
How is tuberculosis transmitted? Everything about the causes, symptoms, and treatments for this disease.
Symptoms and Causes
Tuberculosis is an infection that primarily affects the lungs and is caused by the Koch bacillus (Mycobacterium tuberculosis). Although it is more common in developing countries, cases occur worldwide.
According to the World Health Organization (WHO), tuberculosis is once again the leading cause of death from infectious diseases in 2023, surpassing COVID-19.
It is possible for the bacillus to enter the body but not spread. In these cases, it is referred to as latent or inactive tuberculosis.
Depending on the areas of the body affected, there are two types of tuberculosis:
- Pulmonary Tuberculosis: Affects the lungs and lymph nodes.
- Primary Tuberculosis: Develops immediately after the infection occurs and, although it does not show symptoms, leaves lifelong scars on these organs. It is more common in children.
- Post-primary Tuberculosis: Usually appears around two years after infection and is more aggressive. It can spread to other organs.
- Extrapulmonary Tuberculosis: Spreads to other parts of the body such as bones (bone tuberculosis), skin (cutaneous tuberculosis), genitals (genitourinary tuberculosis), meninges (meningeal tuberculosis), or the central nervous system. The so-called miliary tuberculosis spreads the infection through the blood or lymphatic fluid.
Although it is a serious and potentially fatal disease, current treatments are highly effective, and when accessible, symptoms improve in a short time.
Symptoms
Active tuberculosis, the one that causes symptoms, is characterized by:
- Persistent dry cough
- Coughing up blood
- Chest pain
- Fatigue
- Sweating, especially at night
- Fever
- Weight loss
Causes
Tuberculosis is an infection caused by the Koch bacillus. Transmission occurs from person to person through tiny droplets that are released when talking, coughing, or sneezing. Continuous and prolonged contact is usually necessary, such as living with or working closely with the infected person.
Risk Factors
The likelihood of contracting tuberculosis is higher in the following cases:
- Living with someone with active tuberculosis
- Attending crowded places
- Caring for infected patients
- Traveling to areas with high incidence, such as Sub-Saharan Africa, South America, Western Pacific, Southeast Asia, Russia, China, or Afghanistan.
The risk of developing active tuberculosis increases when the immune system is weakened or in the presence of the following conditions:
- HIV or AIDS
- Malnutrition
- Diabetes
- Kidney disease
- Alcoholism
- Smoking
Complications
If tuberculosis spreads through the blood, it can lead to:
- Meningitis
- Joint injuries
- Damage to the liver or kidneys
- If not treated properly, it can lead to death.
Prevention
To prevent the spread of tuberculosis, it is recommended to remain isolated during the first two weeks of treatment. Additionally, it is advised to cover the nose and mouth with a mask or handkerchief when coughing and to ventilate the room frequently.
In countries with higher incidence, it is recommended to vaccinate babies. In developed countries, such as Spain, universal vaccination is discouraged.
What doctor treats tuberculosis?
Pulmonologists are the specialists who diagnose and treat tuberculosis.
Diagnosis
To diagnose tuberculosis, a medical history is taken, and a physical examination is conducted, including palpating the lymph nodes to check for swelling. Afterward, tests are performed, including:
- Mantoux Test, also known as the tuberculin test: Antigens from the Koch bacillus are injected under the skin, and two to three days are waited to check for a reaction in the area (redness and warmth). If the result is positive, it means the patient has been in contact with Mycobacterium tuberculosis, but it does not confirm the infection.
- Blood tests and sputum cultures: These determine whether the infection is active or latent.
- Chest X-ray or CT scan: These allow for viewing spots on the lungs, indicating that the immune system has reacted to the bacteria.
Treatment
Since tuberculosis is a bacterial infection, it is treated with antibiotics. However, the Koch bacillus is highly resistant, so it is often necessary to use a combination of several medications to be effective.
Typically, isoniazid, rifampicin, and pyrazinamide are used during the first few months, and isoniazid and rifampicin are continued for another four months.
