Characteristics of Fungal Diseases

1. Intoxication (Mycotoxicosis)  Fungi release toxins into the environment, or have them intrinsically. One example is psilocibin, which has an effect on the CNS; another example is LSD, which is derived from fungi. An example of an indirect effect is when fungi grow on wheat, corn, or peanuts and produce aflatoxin and people eat the food. Even more indirect is when animals eat contaminated food and the people eat the meat or milk from the animals and get sick. The toxins don’t have to be just poison that kills you right then, they can also be carcinogenic and mutagenic.

2. Allergies  Spores in the environment make people who are susceptible allergic. People in a highly contaminated environment can get allergies even if they’re not susceptible. The allergies are usually in the respiratory tract and have asthma-like symptoms.

3. Infection (Mycosis)  Fungi grow on or in the body, produce metabolites, and cause infection.

Fungal infections are classified from outside to inside:

1. Superficial/Cutaneous  outer layers of skin, hair, nails, and mucosal surfaces. Infection caused by contact, and sometimes in the skin by endogenic means.

2. Subcutaneous  dermis, subcutaneous tissues, muscle, fascia, lymph. Caused by penetration through the skin, usually after some sort of injury, and generally develops real slow.

3. Deep/ Systemic  internal organs or disseminated throughout body. Caused by inhalation and endogenic means.

1. Primary  caused by organisms that would cause an infection in healthy individuals. For example: dimorphic fungi like hystoplasmosis

2. Opportunistic  I believe we all know what the meaning of this by now, but in case you forgot, it’s lower virulence or floral fungi that only cause a problem in people with a compromised immune system.

Category: Microbiology Notes