Fungal diseases are called mycoses

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Fungal diseases are called mycoses and those affecting humans can be divided

into four groups based on the level of penetration into tissues:

http://www.diseasescausedbyfungi.com/5499/four-groups-of-mycoses/

1. Superficial mycoses are caused by fungi that grow only on the surface of the

skin or hair.

2. Cutaneous mycoses or dermatomycoses include such infections as athlete's foot

and ringworm, in which growth occurs only in the superficial layers of skin,

nails, or hair.

3. Subcutaneous mycoses penetrate below the skin to involve the subcutaneous,

connective, and bone tissue.

4. Systemic or deep mycoses are able to infect internal organs and become widely

disseminated throughout the body.

These are the most severe fungal diseases. An unsuspecting person may inhale the

pathogenic fungal spores. Some spores stay in the lungs and grow while others

enter the bloodstream, travel around the body and infect other organs. Most

fungal infections are due to opportunistic pathogens; these affect people who

are already ill or have a suppressed immune system (e.g. in patients who have

been given an organ transplant, or in AIDS patients). In a perfectly healthy

person the fungus would not normally cause disease. True pathogens can cause

disease in even the healthiest person. Like bacteria, fungi can produce toxins.

Fungal toxins are called mycotoxins and the diseases they cause are called

mycotoxicoses. Several food items are particularly susceptible to fungal disease

including bread, dried pasta, peanuts and stored grains and cereals. All of

these are dry foods which should be stored in dry conditions. When stored in the

wrong conditions of high temperature and high humidity, mycotoxins can be found

as a result of fungal (`mould') growth in the stored material. The most

widespread and dangerous of these are the aflatoxins produced by the mould

called Aspergillus flavus. These are carcinogenic, which means they can cause

cancer. Aflatoxins pose a serious threat to both humans and domestic animals

because the mould grows on poorly-stored grain and animal feed. When eaten, the

toxin is stored in the liver where it can eventually cause hepatitis and liver

cancer.

The most common type of subcutaneous mycosis seen around the world is

sporotrichosis, which occurs most often in gardeners and farmers who come in

direct contact with soil. This is a chronic infection caused by the fungus

Sporothrix schenckii, occurring in three forms. The `cutaneous lymphatic form'

is characterized by a single pustule or nodule that forms at the site of

invasion. This is followed by lymphatic spread and the development of numerous

subcutaneous lesions. This `disseminated form' is marked by multiple, painless

cutaneous or subcutaneous nodules, which can form into ulcers or abscesses

involving the muscles, joints, bones, eyes, gastrointestinal system, mucous

membranes, and nervous system. The `pulmonary form' results from the inhalation

of spores, but produces much the same forms of the disease.

Other forms of subcutaneous mycoses occur mostly in the tropics and subtropics

and are caused by several fungal species. These conditions are called

chromomycosis (producing wartlike nodules that can ulcerate) and maduromycosis

(or mycetoma — a chronic slowly progressive destructive infection involving

several layers of skin, producing abscessing granulomas). Treatment is difficult

and often requires surgical removal of the offending tissues.

Dermatomycoses is a superficial fungal infection that penetrates only the

epidermis, hair, or nails. About thirty different species of the genera

Epidermophyton, Microsporum, and Trichophyton (collectively known as

dermatophytes) cause infections commonly known as athlete's foot, jock itch, and

ringworm. The term tinea, along with the area of body involved, is also used

when referring to these infections. Tinea is Latin for worm or grub because the

infections were originally thought to be caused by worm-like parasites.

Different species afflict different anatomical areas in different ways.

Dermatophyte fungi typically causes scaly lesions that tend to be circular

(ringworm). Dermatophyte fungi are molds, but there are yeasts that also cause

skin infections. Trichophyton rubrum and T. mentagrophytes are the dermatophytes

that cause athelete's foot. Malassezia furfur causes a type of dandruff, as well

as an infection known as Pityriasis versicolor (formerly Pityrosporum ovale

andP. orbiculare). M. furfur is actually a complex of seven species that are

normally harmless, but, for some reason, turn pathogenic at times. Infection

produces a flaking skin rash and either a bleaching of the skin or a deposit of

more pigment to the area. Lesions are generally found on the trunk, and sport a

golden yellow florescent color when an ultraviolet light is shone on them.