Histoplasmosis is a common fungus disease, systemic in nature but with principal manifestations in the lungs. It may be quite benign, and then again quite serious. It is often fatal in the chronic reinfection types and is a great imitator, especially of tuberculosis, since it cannot be distinguished from the latter by x-rays.
The organism was discovered and named Histoplasma capsulatum by Samuel Taylor Darling in 1905. In 1912, Henrique da Rocha-Lima definitely identified Darling's organism as a yeast. The first well-documented case in humans to be reported in the U. S. was in 1926, when Drs. William Riley and Cecil J. Watson described a case of histoplasmosis occurring in a resident of Minnesota. The first successful culture of the organism was carried out by Dr. William A. De Monbreun in 1933. The medical profession has become more and more cognizant of this disease since the 1940's and has learned