Classical radiographic features of patients presenting with silicosis
are diffuse interstitial shadowing with subsequent enlargement of hila
r nodes, sometimes with ''eggshell'' calcification. Five case historie
s are described of workers who were exposed to silica and presented in
itially with bilateral hilar lymphadenopathy without radiographic evid
ence of interstitial lung disease. One case progressed to show feature
s of silicosis.