Final answer:
Presumed Ocular Histoplasmosis (POHS) is a condition characterized by inflammation of the conjunctiva with nodules. It is caused by Histoplasma capsulatum, a dimorphic fungus primarily found in soil. Histoplasmosis is acquired by inhaling microconidial spores in the air, and while many people are exposed to the fungus, only a few experience symptoms.
Step-by-step explanation:
Presumed Ocular Histoplasmosis (POHS) is a condition characterized by inflammation of the conjunctiva with nodules, which are dome-shaped structures that are red at the base and pale on top. POHS is caused by Histoplasma capsulatum, a dimorphic fungus that primarily grows in the soil, especially in areas rich in bat or bird feces.
Histoplasmosis itself is a fungal disease of the respiratory system, commonly found in certain regions of the United States, Central and South America, and other parts of the world. It is acquired by inhaling microconidial spores in the air.
Although the incidence of histoplasmosis exposure is high in endemic areas, relatively few individuals exposed to the fungus actually experience symptoms. The most affected individuals are the very young, the elderly, and those with compromised immune systems.