Molds
There are many different species of molds that can cause reactions. Below is a list of common types of molds.
Ascospores: Ascospores are ubiquitous in nature and are commonly found in the outdoor environment.
Basidiospores: Basidiospores agents of wood rot and have the potential to produce a variety of toxins. Members of this family produce type I and III fungal hypersensitivity reactions.
Cladosporium: Cladosporium spores are commonly found on dead plants, food, textiles and a variety of other surfaces. This genus compromises perhaps the most common isolates in both the indoor and outdoor environment. Some species produce a mycotoxin, epicladosporic acid that acts in an immunosuppressive manner.
Smuts, Periconia, Myxomycetes: Smuts and Myxomycetes are parasitic plant pathogens and can produce type I fungal hypersensitivity reactions. All three are typically grouped together due to their association with plants, the outdoors and because they share similar microscopic morphology.
Penicillium/Aspergillus: Penicillium spores are ubiquitous in environment. These spores are easily aerosolized and can cause a variety of symptoms including allergic reactions, keratitis, hypersensitivities and pnuemonitis. Most are of these symptoms occur if the individual is immunocompromised in some way (HIV, cancer, etc). Penicillium species also produce a wide variety of mycotoxins including but not limited to ochratoxin, patulin, and citrinin.
Aspergillus species can produce a variety of symptoms and disease for an affected individual. There are over 175 different Aspergillus species and they can produce type I and III fungal hypersensitivities. Also included in this group are the spores of the genera Trichoderma, Acremonium, Verticillium and Paecilomyces. Small, round spores of this group lack the necessary distinguishing characteristics when seen on non-viable examination. Therefore, all of the above are included in the category of Penicillium/Aspergillus group spores.
Alternaria: This genus compromises a large number of saprobes and plant pathogens. In humans, it is recognized to cause type I and type III allergic responses. Because of the large size of the spores, it can be deposited in the nose, mouth and upper respiratory tract. It has been known to cause Baker’s asthma, farmer’s lung, and hay fever. Certain species of Alternaria have the capability to produce tenuazonic acid and altertoxin, both mycotoxins. There are approximately 40-50 different species of Alternaria. It is one of the more common fungi found in nature.
Arthrinium: This fungus is a saprobe and is found on plant material. There is no known mycotoxin production and only one of approximately twenty species of Arthrinium is a potential allergen.
Curvularia: Curvularia species is found on plant material and is considered a saprobe. It has been reported to cause type I hypersensitivity and to be a cause of allergic fungal sinusitis but further studies are needed regarding human sensitivity.
Stachybotrys: Stachybotrys grows well on wet media, preferably containing cellulose. It proliferates in the indoor environment, growing on wallpaper, gypsum board, and textiles. It has worldwide distribution and has been reported to cause dermatitis, cough, rhinitis, headache, although no definitive reports of human infections have been verified. It has the ability to cause type I hypersensitivity and some species produce the following mycotoxins: satratoxin, verrucarins and roridins.
Pestalotiopsis is a plant fungal disease that is considered usually a minor disease. It attacks foliage that has been injured or weakened by unfavorable weather or growing conditions. Usually, the killed foliage is near the base of the plant and where foliage is relatively dense. The disease usually starts at the tip of the foliage and progresses towards the leaf base. The color of the foliage goes from green to yellowish, then to a dark brown that can look almost black. The disease may kill the smaller twigs where the infected needles died.
Hyphal elements: Hyphal elements are filamentous structures of a fungus
Algae: Algae are microscopic plants that are found in fresh water, marine water and in damp environments. The increased presence of algae would indicate a wet environment.
Geotrichum: Geotrichum species is commonly found in dairy products and the soil. It causes geotrichosis, which can produce lesions in the mouth, intestines and other areas. Typically, these infections only occur in the immunocompromised host. Geotrichum species also has the potential to be an allergen
Epicoccum: Epicoccum is a saprophyte and considered a weakly parasitic secondary invader of plants, moldy paper and textiles. Epicoccum is usually isolated with either Cladosporium species or Aureobasidium species. It produces the mycotoxins flavipin and epicorazine A&B. It also has the potential to produce type I fungal hypersensitivity reactions
Pithomyces: Pithomyces is commonly found on grass and decaying plant material. It has the potential to produce the mycotoxin, sporidesmin
Chaetomium: This genus is often found on materials containing cellulose, or other wet materials. It is also considered part of the ascomycete group because its spores are released from a sac called an ascus. Chaetomium can produce type I fungal hypersensitivity and has caused onychomycosis (nail infections). Chaetomium species can also produce mycotoxins, one of which being chaetomin.
Ulocladium: Ulocladium species is reported to be a major allergen. It can be found on many types of materials, but mostly found on decaying materials. Rarely it can cause subcutaneous infections in humans. It has a high water requirement and its ability to produce mycotoxins is not fully understood
Rusts: Rusts are serious plant pathogens associated with cereal crops. These smut teliospores can serve as potential allergens.
Clear brown: These spores are usually seen as round clear, brown spores. There are no distinguishing features to allow complete identification