<unk>  is a form of tuberculosis that is the result of Mycobacterium tuberculosis travelling to extrapulmonary organs, such as the liver, spleen and kidneys. Although it is well understood that the bacteria spread from the pulmonary system to the lymphatic system and eventually the blood stream, the mechanism by which this occurs is not well understood. One proposed mechanism is that tuberculous infection in the lungs results in erosion of the epithelial layer of alveolar cells and the spread of infection into a pulmonary vein. Once the bacteria reach the left side of the heart and enter the systemic circulation, they may multiply and infect extrapulmonary organs. Once infected, the cell-mediated immune response is activated. The infected sites become surrounded by macrophages, which form granuloma, giving the typical appearance of<unk> . Alternatively, the bacteria may attack the cells lining the alveoli and enter the lymph node(s). The bacteria then drain into a systemic vein and eventually reach the right side of the heart. From the right side of the heart, the bacteria may seed—or re-seed as the case may be—the lungs, causing the eponymous<unk> " appearance.
Miliary tuberculosis
Tuberculosis
Extrapulmonary tuberculosis
Multidrug-resistant tuberculosis
Melioidosis
Chronic pulmonary aspergillosis
Vietnamese tuberculosis
Primary inoculation tuberculosis