There may be pleural involvement, with effusion, empyema or massive obliterative fibrosis. It may be limited to lungs or be a systemic involvement. In the pulmonary form, spread is probably via pulmonary lymphatics to thoracic duct, jugular vein and thence back to both lungs via the pulmonary arteries. Erosion into a pulmonary artery can cause similar results. Diagnosis may be difficult, as the organism may not be seen in biopsy slides or smears.
Organism grows slowly.
Early detection may be made by finding specific DNA sequences in cultures. There is concern about resistant strains. Most cases respond to currently available multiple antimicrobial treatment. TB is common in context of HIV infection.