Types of fungal infection
Examples of common fungal infections include:
- Tinea, a dermatophyte fungus that lives on human skin and promotes a reaction as it grows through the skin by small filaments called hyphae, causing symptoms including, inflammation, itching and rash, which can become severe. Tinea can infect many parts of the body causing infections like athlete's foot (tinea pedis), ringworm or tinea of the body (tinea corporis), tinea of the groin or jock itch (tinea cruris) and tinea of the scalp (tinea capitis).
- Candida, a yeast that normally inhabits the gastrointestinal tract but when immunity is low or following a course of antibiotics, it can become overgrown and cause an infection called candidiasis or thrush. Areas infected by Candida include mucous membranes usually in the mouth, throat and genitals; Candida can also infect the skin and if the infection becomes systemic this can be more serious.
- Infections of the finger nails and toe nails (onychomycosis) can be caused by Tinea or Candida, also by moulds, which are a different type of fungus.
- Malassezia, a yeast normally found in the skin that can overgrow and cause problems like dandruff, when the rate at which dead skin cells are shed and replaced begins to speed up, as a reaction to irritation by the fungus.
- Histoplasma capsulatum is a fungus that normally lives in the soil, and inhalation of its spores can cause histoplasmosis, a systemic fungal infection that affects internal organs causing flu-like symptoms.
Types of anti-fungal medication
Most antifungals work by the same mechanism of action to kill the fungus causing the infection and prevent its spread. They act by inhibiting the fungal enzyme, squalene epoxidase, which prevents the synthesis of ergosterol, an important component of fungal cell membrane that is not found in animal cells. This weakens the fungal cell membrane, causing the cell contents to leak out which kills the fungus. Other antifungals bind to ergosterol in the membrane which has the same effect. Antifungals include:
- Terbinafine, a broad spectrum antifungal drug that is used to treat a variety of fungal infections, and is particularly effective against tinea and candida. It is available as a cream for topical treatment and as tablets for oral administration.
- Miconazole oral gel an antifungal drug, belonging to the imidazole group of antifungals that is used as a topical treatment for oral thrush.
- Fluconazole a broad-spectrum antifungal drug belonging to the triazole group that is used to treat thrush and tinea and is available for oral administration as capsules and tablets.
- Ketoconazole, a synthetic broad-spectrum antifungal drug that is used to treat a variety of fungal infections in several parts of the body, including pityriasis of the skin, candidiasis or thrush of the mouth and vagina and also systemic fungal infections. It is available as a cream or shampoo for topical treatment and as tablets for oral administration.