Give a differential for miliary nodules on a chest radiograph.
A reasonable differential should include miliary metastases (e.g. thyroid), TB (and other atypical infection), hypersensitivity and - if there is an appropriate clinical history - pneumoconioses (e.g. silicosis).
What does miliary nodulation in TB represent?
The miliary nodules represent haematogenous spread of uncontrolled TB infection and represents a relatively poor prognosis.
Given the clinical history, what is the most likely diagnosis?
As a reminder, the clinical history was of lethargy, night sweats and haemoptysis. The most likely diagnosis, is therefore clearly going to be TB.
Zoomed cropped image from the left upper zone demonstrates innumerable well defined ~2mm nodules.
Milet seeds. Photo credit: Elke Wetzig Original file: http://en.wikipedia.org/wiki/File:Hirsekoerner.jpg Licence: CC-SA-BY