Histoplasmosis is caused by which type of organism?

Histoplasmosis is caused by which type of organism?

• A. A fungus
• B. A bacterium
• C. A virus
• D. A protozoan

Answer: (A)

Histoplasmosis is caused by a fungus. The organism is Histoplasma capsulatum, a dimorphic fungus that grows as mold in the environment and as yeast in human tissues. This fungal nature explains why it’s classified with fungal infections and treated with antifungals, not antibiotics or antivirals. It’s distinct from a bacterium (a prokaryote), a virus (an acellular particle), or a protozoan (a different kind of single-celled eukaryote), which is why those options don’t fit. In the eye, ocular histoplasmosis syndrome reflects the same fungal pathogen.

Histoplasmosis is caused by a fungus. The organism is Histoplasma capsulatum, a dimorphic fungus that grows as mold in the environment and as yeast in human tissues. This fungal nature explains why it’s classified with fungal infections and treated with antifungals, not antibiotics or antivirals. It’s distinct from a bacterium (a prokaryote), a virus (an acellular particle), or a protozoan (a different kind of single-celled eukaryote), which is why those options don’t fit. In the eye, ocular histoplasmosis syndrome reflects the same fungal pathogen.