Key points about tuberculosis
- Tuberculosis is a bacterial infectious disease caused by Mycobacterium tuberculosistransmitted via the air from contagious pulmonary forms.
- After infection, the bacteria can be eliminated, remain latent without symptoms, or progress to tuberculosis disease, most often pulmonary but sometimes extrapulmonary.
- It remains a major global public health problem, affecting mainly populations in situations of social or medical vulnerability.
- The diagnosis is based on clinical, radiological and especially microbiological evidence.
- Treatment is lengthy, combining several antibiotics, and prevention relies on screening, early treatment and BCG vaccination in children.
What is tuberculosis?
Tuberculosis is a bacterial infectious disease caused by Mycobacterium tuberculosisTuberculosis, also known as Koch's bacillus, is primarily transmitted through the air by inhaling droplets expelled by a person with contagious pulmonary tuberculosis, particularly when coughing or sneezing. After infection, the bacteria can be eliminated by the immune system, remain dormant without causing symptoms, or develop into active tuberculosis. Tuberculosis most often affects the lungs, but can also affect other organs (lymph nodes, bones, kidneys, genitourinary system, central nervous system).
Tuberculosis worldwide
Tuberculosis remains one of the main causes of death from infectious disease worldwide. Each year, it is estimated that approximately 10 million people develop tuberculosis disease and that approximately 1,2 to 1,3 million deaths These deaths occur among people not infected with HIV, in addition to several hundred thousand deaths among people living with HIV. The disease is present in all countries, but its burden is very unevenly distributed. Approximately 85% of cases occur in about thirty high-incidence countries, mainly in South and Southeast Asia, Sub-Saharan Africa and in certain regions of Western PacificTuberculosis is closely linked to social and economic factors such as poverty, overcrowding, malnutrition, and limited access to healthcare. Certain populations are particularly vulnerable, including people living with HIV, children, the elderly, incarcerated individuals, migrants, and those experiencing precarious living conditions. A major public health challenge is the emergence of tuberculosis resistant to anti-tuberculosis drugsIn particular, multidrug-resistant (MDR-TB) and extensively drug-resistant (XDR-TB) complicate treatment and undermine disease control efforts. In low-incidence countries, such as those in Western Europe, tuberculosis persists in the form of sporadic cases, often concentrated in at-risk groups, and remains a public health issue.
Symptoms of tuberculosis
Tuberculosis usually develops gradually. Symptoms depend on the location of the disease. pulmonary tuberculosisThe most frequent and only contagious form, classically manifests as a persistent cough lasting several weeks, sometimes associated with expectoration or bloody sputum. It is often accompanied by prolonged fever, night sweats, An weight loss, An significant fatigue and a deterioration of the general condition. The forms extrapulmonary These conditions can cause a variety of symptoms depending on the organ affected, such as chronic lymphadenopathy, bone pain, neurological disorders, or kidney damage. In some people, particularly children and immunocompromised individuals, the progression can be rapid and severe.
The diagnosis
The diagnosis of tuberculosis is based on a combination of clinical, radiological, microbiological, and sometimes histological findings. Confirmation relies on the identification of Mycobacterium tuberculosisIn pulmonary tuberculosis, sputum examination is central, with the search for bacilli, culture, and rapid molecular tests allowing identification of the bacteria and assessment of resistance to antituberculosis drugs. Chest imaging, particularly chest X-ray, is an essential tool for guiding the diagnosis. Further investigations are necessary if extrapulmonary tuberculosis is suspected. latent tuberculosis infection, asymptomatic and non-contagious, can be detected by immunological tests (tuberculin TST or IGRA tests) in exposed or at-risk individuals.
Tuberculosis treatment
The treatment of tuberculosis is based on a prolonged association of antibiotics, in order to ensure a cure and prevent the development of resistance. Drug-sensitive tuberculosis is treated with an initial four-drug regimen followed by a two-drug regimen, for a total duration of at least six monthsTreatment should be administered under regular medical supervision. Adherence to the prescribed regimen is a key element of therapeutic efficacy. Resistant forms require longer, more complex, and sometimes less well-tolerated treatment regimens, with specialized follow-up. Preventive treatment is recommended for certain individuals with latent tuberculosis infection to reduce the risk of progression to active tuberculosis.
Tuberculosis prevention
Tuberculosis prevention relies on several complementary approaches. early detection and Rapid treatment of contagious cases These are the most effective measures for interrupting transmission. Screening for and treating latent tuberculosis infection are particularly important in high-risk individuals, including contacts of cases, immunocompromised individuals, and exposed professionals. The tuberculosis vaccine known as BCG, or Calmette-Guérin bile acid vaccine, was developed at the Pasteur Institute in Lille in 1921 by Dr. Albert Calmette, a physician and the institute's first director, and Dr. Camille Guérin, a veterinarian. BCG vaccination It primarily protects young children against severe forms of tuberculosis, although its effectiveness against pulmonary forms in adults varies. It can be administered at Tuberculosis Control Centers (CLAT) or Maternal and Child Health (PMI) clinics. Finally, improving living conditions, combating poverty, ensuring universal access to healthcare, and managing comorbidities, particularly HIV, are essential elements for the sustainable control of tuberculosis worldwide.
FAQ
Tuberculosis is a bacterial infectious disease caused by Mycobacterium tuberculosistuberculosis, also known as Koch's bacillus, most often affects the lungs, but can also affect other organs such as the lymph nodes, bones, kidneys, or nervous system. After infection, the bacteria can be eliminated by the body, remain dormant without symptoms, or develop into active tuberculosis.
Tuberculosis is primarily transmitted through the air, by inhaling droplets expelled by a person with contagious pulmonary tuberculosis, particularly when they cough or sneeze. Extrapulmonary forms are not contagious.
Symptoms usually develop gradually. Pulmonary tuberculosis most often manifests as a persistent cough lasting several weeks, sometimes accompanied by bloody sputum, prolonged fever, night sweats, weight loss, and severe fatigue. Extrapulmonary forms cause symptoms that vary depending on the organ affected.
The diagnosis is based on a combination of clinical, radiological, and especially microbiological findings. It is confirmed by the detection of Mycobacterium tuberculosis, particularly from sputum in pulmonary forms. Imaging tests, such as chest X-rays, complete the evaluation. Latent tuberculosis infection can be detected by immunological tests in exposed or at-risk individuals.
Tuberculosis treatment involves a combination of several antibiotics for at least six months, with regular medical monitoring. Prevention relies on early detection, prompt treatment of contagious cases, and management of latent infection in at-risk individuals. BCG vaccination, developed at the Pasteur Institute in Lille, primarily protects young children against severe forms of the disease.
