Aspergillus (Aspergillosis)

General: This ubiquitous filamentous fungus is the most commonly isolated invasive fungal infection and the second most common opportunistic mycosis (following candida). It may infect virtually any organ or system, or be systemic. Collections may form in any cavity (aspergilloma), usually lung or kidney. Also produces aflatoxin, a carcinogen best associated with hepatocellular carcinoma.

Clinical: Seen in either opportunistic infections, allergic states, or toxicoses; it primarily affects the immunocompromised.

Resistance:

Growth characteristics: Differentiates the main pathogenic species.

Morphology: That which is common to all species includes: Septate and hyaline hyphae. Conidiophores originate from the basal foot cell located on the supporting hyphae and terminate in a vesicle at the apex. The morphology and color of the conidiophore vary from one species to another. Covering the surface of the vesicle entirely ("radiate" head) or partially only at the upper surface ("columnar" head) are the flask-shaped phialides which are either uniseriate and attached to the vesicle directly or are biseriate and attached to the vesicle via a supporting cell, metula. Over the phialides are the round conidia (2-5 µm in diameter) forming radial chains.

Common/important pathogens: