The radiographic hallmark of miliary TB is:

The radiographic hallmark of miliary TB is:

• A. Pleural effusion without nodules
• B. Isolated cavitary lesion in upper lobes
• C. Numerous tiny nodules resembling millet seeds scattered throughout the lungs
• D. Large consolidative lobar pneumonia

Answer: (C)

Miliary TB results from hematogenous spread of Mycobacterium tuberculosis, causing numerous tiny granulomas to seed the lungs. On chest radiographs these appear as a diffuse, fine pattern of countless small nodules—often about 1–2 mm in size—distributed throughout both lungs, giving a millet seed-like appearance. This diffuse nodularity is the defining radiographic feature of miliary TB and helps distinguish it from other TB patterns. The other patterns do not fit this presentation: pleural effusion without nodules isn’t the disseminated, seed-like pattern; an isolated cavitary lesion in the upper lobes points to reactivation TB rather than miliary spread; and a large consolidative lobar pneumonia reflects a focal infection rather than widespread tiny nodules.

Miliary TB results from hematogenous spread of Mycobacterium tuberculosis, causing numerous tiny granulomas to seed the lungs. On chest radiographs these appear as a diffuse, fine pattern of countless small nodules—often about 1–2 mm in size—distributed throughout both lungs, giving a millet seed-like appearance. This diffuse nodularity is the defining radiographic feature of miliary TB and helps distinguish it from other TB patterns.

The other patterns do not fit this presentation: pleural effusion without nodules isn’t the disseminated, seed-like pattern; an isolated cavitary lesion in the upper lobes points to reactivation TB rather than miliary spread; and a large consolidative lobar pneumonia reflects a focal infection rather than widespread tiny nodules.