Fulminant infection with Mycobacterium tuberculosis disseminated via bloodstream
Nodules are < 3mm, uniform in size, usually too numerous to count and noncalcified
May have background of ground-glass opacities or septal thickening
The nodules are distributed randomly with respect to secondary pulmonary lobules
Typical miliary infection may not be seen radiographically for 3-6 weeks after hematogenous dissemination