AAB Medical Technologist (MT) – Microbiology 2025 – 400 Free Practice Questions to Pass the Exam

The tissue phase of Histoplasma capsulatum is characterized by the presence of spherical yeast cells. This fungus is known for causing histoplasmosis, and during its tissue phase, it typically converts from mycelial form into a yeast form that is small and round.

In a clinical context, when histoplasmosis is diagnosed, particularly in an individual with an active or disseminated infection, the tissue samples will predominantly show these yeast cells, which are often intracellular, residing within macrophages. This observation is crucial for proper diagnosis, as recognizing these yeast cells can aid in confirming infection with Histoplasma capsulatum.

The confusion might arise with the other choices, which are associated with different fungi. For example, microconidia and chlamydospores are forms seen in various fungi but not specifically linked to the tissue phase of Histoplasma capsulatum. Tuberculate macroconidia are more characteristic of other species like Aspergillus and are not representative of the tissue phase of Histoplasma.