How does miliary tuberculosis develop?

Miliary tuberculosis develops when the primary tuberculosis infection spreads throughout the body via the bloodstream. While the exact sequence of events leading to this disseminated form is not fully understood, it occurs most frequently in individuals with compromised immune systems, such as infants, the elderly, and those with conditions like AIDS or those who have received organ transplants.12

In this process, tubercle bacilli enter the circulatory system and can travel to nearly any tissue, including the lymph nodes, bones, joints, kidneys, and the meninges covering the brain. When it occurs in the lungs, it manifests as a diffuse spread of the infection, which appears on a chest radiograph as numerous small, scattered shadows. Because this form of the disease is highly fatal if left untreated, prompt medical intervention is essential to prevent further systemic spread.12