This Giemsa-stained photomicrograph reveals some of the histopathologic details displayed in a liver tissue specimen extracted from a patient ill with histoplasmosis, which is caused by the fungal organism, Histoplasma capsulatum. Note the numerous yeast-staged cells contained within a macrophage in the center of this view.
There are multiple tests available to diagnose histoplasmosis. One way to diagnose the infection is to perform a fungal culture. Doctors take small samples from tissues, or body fluids, such as blood, sputum, bone marrow, liver, or skin and see if the fungus will grow from these samples in a laboratory.
A urine test is available that can check for recent infection from Histoplasma, by measuring the presence of antigen. Histoplasmosis can also be diagnosed by looking at a small sample of infected tissue under a microscope. A blood test can measure prior exposure to the fungus by detecting Histoplasma antibodies.