After the demonstration of a high degree of correlation between histoplasmin skin sensitivity and intrathoracic calcification in the Ohio and Mississippi River basins it was predicted that cases of active histoplasmosis would be recognized with considerably increased frequency. This prediction appears to have materialized. The active form of the disease is now commonly encountered, and numerous verified cases have been recorded in the recent literature.1-8
Various roentgen manifestations of intrathoracic histoplasmosis have been depicted and their course described.9-14 For the most part, these findings have fallen into three main categories: (1) an acute disseminated form with miliary or small patchy densities diffusely distributed throughout the lungs, sometimes encountered in epidemics8,15,16; (2) a localized pneumonic form, and (3) the solitary nodule ("coin" lesion, histoplasmoma) of chronic and asymptomatic nature. Each of these types may be associated with hilar and/or mediastinal lymph node enlargement of variable degree and extent,