Mycosis

The Term mycosis (plural: mycoses) refers to conditions in which fungi pass the resistance barriers of the human or animal body and establish infections.

Classification

Mycoses are classified according to the tissue levels initially colonized:

1. Superficial mycoses - limited to the outermost layers of the skin and hair.
2. Cutaneous mycoses - extend deeper into the epidermis, as well as invasive hair and nail diseases. These diseases are restricted to the keratinized layers of the skin, hair, and nails. Unlike the superficial mycoses, host immune responses may be evoked, resulting in pathologic changes expressed in the deeper layers of the skin. The organisms that cause these diseases are called dermatophytes. The resulting diseases are often called ringworm (even though there is no worm involved) or tinea. Cutaneous mycoses are caused by Microsporum, Trichophyton, and Epidermophyton fungi, which together comprise 41 species.
3. Subcutaneous mycoses - involve the dermis, subcutaneous tissues, muscle, and fascia. These infections are chronic and can be initiated by piercing trauma to the skin, which allows the fungi to enter. These infections are difficult to treat and may require surgical interventions such as debridement.
4. Systemic mycoses due to primary pathogens - originate primarily in the lungs and may spread to many organ systems. Organisms that cause systemic mycoses are inherently virulent. Generally, primary pathogens that cause systemic mycoses are dimorphic.
5. Systemic mycoses due to opportunistic pathogens - infections of patients with immune deficiencies who would otherwise not be infected. Examples of immunocompromised conditions include AIDS, alteration of normal flora by antibiotics, immunosuppressive therapy, and metastatic cancer. Examples of opportunistic mycoses include Candidiasis, Cryptococcosis and Aspergillosis.

Another example of a fungal infection is Tinea versicolor: Tinea versicolor is a fungus infection that commonly affects the skin of young people, especially the chest, back, and upper arms and legs. Tinea versicolor is caused by a fungus that lives in the skin of almost all adults. It doesn't usually affect the face. This fungus produces spots that are either lighter than the skin or a reddish-brown. There may be just a few spots or lots of spots. Tinea versicolor is caused by a fungus that lives in the skin of almost all adults. This fungus exists in two forms, one causes visible spots. Factors that can cause the fungus to become more visible include high humidity and immune or hormone abnormalities. But almost all people with this very common condition are healthy.