miliary tuberculosis
Miliary tuberculosis is TB that has escaped local control and spread through the bloodstream all over the body. The name comes from millet seeds: on imaging the lungs are dotted with countless tiny, evenly spread nodules, each a microscopic colony of bacteria, as if grain had been scattered across both lungs.
It happens when bacteria break into a blood vessel and seed many organs at once — lungs, liver, spleen, bone marrow, the lining of the brain and beyond. Because the infection is everywhere rather than in one spot, symptoms are often vague and systemic: prolonged fever, weight loss and weakness, sometimes without an obvious chest complaint, which can make diagnosis slow.
Miliary TB is a serious, potentially life-threatening form that strikes especially the very young, the elderly and people with weakened immunity, such as those with HIV. A particularly dangerous complication is TB meningitis. It is treatable with standard anti-TB drugs, but early recognition matters because delay raises the risk of severe outcomes.
A patient with HIV presents with weeks of fever and weight loss; chest CT reveals innumerable tiny nodules scattered evenly throughout both lungs — miliary TB.
Bloodstream spread seeding the whole lung field.
The fine, uniform “millet seed” nodules seen throughout both lungs on chest imaging are the radiological signature of miliary spread.