Tuberculose: Infecção Latente e Doença Ativa, Animação. Alila Medical Media Português

Help us produce more videos like this! Support us on Patreon and get free downloads and other great rewards: patreon.com/AlilaMedicalMedia Thank you very much! This video and other related images/videos (in high definition) are available for download under license here: https://www.alilamedicalmedia.com/-/g... Voice and Translation by: Thaís de Oliveira ©Alila Medical Media. All rights reserved. All images and videos from Alila Medical Media are for informational purposes ONLY and are NOT intended to replace professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified healthcare provider with any questions you may have regarding a medical condition. Tuberculosis, or TB, is one of the oldest and most common infectious diseases. It is estimated that approximately one-third of the world's population is infected with TB. Fortunately, only about 5% of these infections progress to active disease. The remaining 95% of infected people are reported to have a dormant or latent infection; they do not develop any symptoms and do not transmit the disease. Tuberculosis is caused by a rod-shaped bacterium, or bacillus, Mycobacterium tuberculosis. An infection begins after the inhalation of mycobacteria present in aerosol droplets released into the atmosphere by a person with an active infection. The transmission process is very efficient, as these droplets can persist in the environment for several hours and the infectious dose is very low—fewer than 10 bacilli are needed to initiate infection. Once in the lung, the bacteria confront the body's first line of defense—alveolar macrophages. The bacteria are ingested by the macrophages but manage to survive within them. Internalization of the bacilli triggers an inflammatory response that brings other defense cells to the area. Together, these cells form a mass of tissue called a granuloma, characteristic of the disease. In its initial phase, the granuloma is centered on infected macrophages and, surrounding the macrophages, other immune system cells. With the activation of cellular immunity, macrophages loaded with bacteria are killed, resulting in the formation of the granuloma's caseous center. Bacteria become dormant but can remain alive for decades. This contained infection is referred to as latent tuberculosis and can persist throughout a person's life without causing any symptoms. The strength of the body's immune response determines whether the infection remains latent or progresses to the next stage. In healthy individuals, the infection can be permanently stopped at this point. Subsequently, the granulomas heal, leaving small calcified lesions. On the other hand, if the immune system is compromised by immunosuppressive medications, HIV infections, malnutrition, aging, or other factors, the bacteria can reactivate, replicate, escape from the granuloma, and spread to other parts of the lungs, causing active pulmonary tuberculosis. This reactivation can occur months or even years after the initial infection. In some cases, the bacteria can also spread to other organs in the body through the lymphatic system or bloodstream. This generalized form of the disease, called disseminated tuberculosis or miliary tuberculosis, occurs most commonly in the very young, the very elderly, and those with HIV infections. Tuberculosis is usually treated with antibiotics. Multiple antibiotics are usually prescribed for many months due to the slow growth rate of the bacteria. It is crucial that patients complete the full course of treatment to prevent the development of drug-resistant bacteria and disease recurrence.