Library · Microorganism
Mycobacterium tuberculosis
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Mycobacterium tuberculosis, also known as Koch's bacillus, is the bacterium that causes tuberculosis. It spreads from one person to another mainly through the air, in droplet nuclei so small that they can stay suspended for several hours.
When those droplets reach the deep part of the lung, the alveolar macrophage, the defense cell that lives down there, swallows the bacilli. And that moment decides what comes next: either the macrophage kills the bacillus, or the bacillus survives inside it and establishes a primary infection.
If it survives, the body changes strategy. T lymphocytes, another kind of defense cell, direct more cells to the site, and together they form a granuloma, a sort of ring of cells built around the infected macrophages, inside the lung parenchyma, the working tissue of the lung. Unable to clear the bacillus, the body walls it off and stands guard around it.
In brief
Mycobacterium tuberculosis is the bacterium that causes tuberculosis, and it spreads from person to person mainly through droplet nuclei that stay suspended in the air for hours.
Alveolar macrophages take up the bacilli, and that is the decisive moment: either they kill them, or the bacilli establish primary infection.
T lymphocytes recruit other cells and form a granuloma around the infected macrophages within the lung parenchyma.
Unable to clear the bacillus, the body walls it off and stands guard around it.
Sources (1)
- National Center for Biotechnology Information, StatPearls PublishingTuberculosis Overview, StatPearlsPublished
This page explains the topic in general terms; it does not tell anyone what treatment to follow.
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