Zygomycosis and the Joplin Tornado
The Zygomycetes
July 2011
Zygomycetes are a group of fungi that are characterized by a number of things. One is that they have rather large hyphae that are nonseptate. We call them pauciseptate because they produce occasional septations and they may have those or they may not have them depending on the organism and how old it is. But also, we know that these zygomycetes produce asexual spores inside of a saclike structure called a sporangium. And the sporangium is located at the tip of a long supporting structure called a sporangiophore. You don’t see that with any other fungi. Consequently, we call these zygomycetes by a certain group name because they have these features. But they are characterized in the literature by having zygospores as a result of sexual reproduction. And the term zygomycosis comes from the fact they can produce zygospores even though you really don’t see these in the clinical laboratory very often, almost never. So the term zygomycosis is used, certainly by me and by many others but others have decided to use the term mucormycosis and that is fine. One of the hallmarks of these infections caused by the zygomycetes is a marked propensity for vascular invasion. And these organisms can penetrate a vessel in a matter of a few hours and cause total occlusion of that vessel based on the fact that platelets, red cells and white cells, aggregate within that vessel and cause a thrombus to form and then the blood flow is prevented from going distal to that. And what happens is, the tissue all downstream becomes necrotic and dies and this is the hallmark of zygomycosis is the dead tissue that actually turns black and you look in sinuses for example, and see black eschar because of all this tissue and destruction and necrosis. One of the things in the case of the Joplin situation is they are able to debride some of those areas where the tissue has become involved.
The Zygomycetes |
Jump to section:
- Introduction
- Tragedy in Joplin
- Unsuspected Fungal Infection Infects Some Joplin Residents
- Zygomycosis
- The Zygomycetes
- The Zygomycetes
- Pauciseptate Hyphae
- Zygomycetes: Basic Structures
- Basic Structures
- Rhizopus Species
- Lichtheimia (Absidia) Species
- Lichtheimia Species
- Mucor Species
- Cunninghamella Species
- Apophysomyces elegans
- Apophysomyces elegans
- Apophysomyces elegans
- Apophysomyces elegans
- Apophysomyces elegans
- Diagnosis of Zygomycosis
- Large Pauciseptate Hyphae—H&E Stain
- Unstained Hyphal Fragment On GMS-Stained Tissue
- Vascular Invasion By Hyphae
- Large Pauciseptate Hyphae—Calcofluor White
- Video Credits
- Questions?


