TB Infection

Improved Essays
TB infection enters its second stage after 7-21 days after initial infection, and it is generally asymptomatic. The TB bacilli start reproducing exponentially within the inactivated macrophages, this eventually result in a rapid expansion of the initial TB bacillus,until the macrophages cannot contain the spread anymore and it will bust and spreading necrotic residue and bacilli throughout the surrounding tissue. Other macrophages will also begin to extravasate from peripheral blood, but they are inactive because they phagocytose the Mycobacterium tuberculosis, therefore they cannot destroy the bacteria anymore.

Stage Three: At stage three, lymphocytes (specifically T cells) will begin to infiltrate and recognize TB antigens. This results in T-cell activation and then it release of cytokines including gamma interferon (IFN). The releasing of IFN triggers the activation of macrophages, which then release lytic enzymes and reactive intermediates that facilitates immune system. These activated macrophages are now capable of destroying MTB. This is the stage where the individual patient becomes tuberculin-positive, which is the result of developing a cell mediated
…show more content…
The reactivated TB bacilli reproduce quickly and form a cavity in the tissue, where the body’s immune system cannot reach them. From this cavity, the TB bacilli quickly spread through the tissue. The center of the tubercle is liquefied and boasts pathologic tissue synonymous with cheesy-looking caseous necrosis, which is crucial for TB to grow extracellularly. The person will develops signs and symptoms of active TB such as coughing with blood, night sweats and fever. Now, the person is highly contagious because his or her sputum contains active TB bacteria. Reactivation is more likely to happen if patient’s immune system is weakened, such as with HIV infection or

Related Documents

  • Improved Essays

    it can be fatal (CDC, 2015b). There are two stages of tuberculosis: Latent TB infection and TB disease. Latent TB infection is when the bacteria lives inside the body, and the host is asymptomatic. This is due to the immune system suppressing the bacteria from growing. In the event that the immune system fails to suppress the bacteria, the bacteria becomes active and multiplies, leading to TB disease. When a person has TB disease, they can spread the bacteria through the air. TB’s main methods of…

    • 1001 Words
    • 5 Pages
    Improved Essays
  • Decent Essays

    medical evaluation of all healthcare workers, including TB screening, prior to employment in hospitals and diagnostics and treatment centers in NY state. The approved TB screening are IGRA (Interferon gamma release assay) and two-step tuberculin skin test (TST). These test are designed to identify latent TB infection. Healthcare workers (HCW) are at high risk of hospital-acquired infections such as TB. They are also at high risk of transmitting TB to patients at the hospital whose immune system is already…

    • 190 Words
    • 1 Pages
    Decent Essays
  • Superior Essays

    O O Angel K. Nickel 0 I 5 as PULMONARY TB 2 Abstract The world was astounded by the dramatic increase in Tuberculosis cases occurring in 1985. The disease strongly affects the lungs however if serious enough it can happen anywhere in the body. An individuals with the TB disease can spread the infection through air. This means that a simple cough, laugh, sneeze, or singing can spread it to anyone within close range. A normal healthy adult can be infected but yet have no complication or symptoms, the…

    • 926 Words
    • 4 Pages
    Superior Essays