Tinea versicolor | |
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Other names | Dermatomycosis furfuracea, [1] pityriasis versicolor, [1] tinea flava, [1] lota |
Specialty | Dermatology |
Causes | Malassezia globosa, Malassezia furfur |
Tinea versicolor (also pityriasis versicolor) is a condition characterized by a skin eruption on the trunk and proximal extremities. [1] The majority of tinea versicolor is caused by the fungus Malassezia globosa , although Malassezia furfur is responsible for a small number of cases. [2] [3] These yeasts are normally found on the human skin and become troublesome only under certain conditions, such as a warm and humid environment, although the exact conditions that cause initiation of the disease process are poorly understood. [2] [4]
The condition pityriasis versicolor was first identified in 1846. [5] Versicolor comes from the Latin versāre 'to turn' + color. [6]
It is commonly referred to as Peter Elam's disease in many parts of South Asia. [7]
The symptoms of this condition include:
Pityriasis versicolor is more common in hot, humid climates or in those who sweat heavily, so it may recur each summer. [10]
The yeasts can often be seen under the microscope within the lesions and typically have a so-called "spaghetti and meatball appearance" [11] as the round yeasts produce filaments.
In people with dark skin tones, pigmentary changes such as hypopigmentation (loss of color) are common, while in those with lighter skin color, hyperpigmentation (increase in skin color) is more common. Because infected skin tans less than uninfected skin, resulting in uneven tanning, the term "sun fungus" is sometimes used. [12] [13]
In cases of tinea versicolor caused by the fungus Malassezia furfur , lightening of the skin occurs due to the fungus's production of azelaic acid, which has a slight bleaching effect. [14]
Tinea versicolor may be diagnosed by a potassium hydroxide (KOH) preparation and lesions may fluoresce copper-orange when exposed to Wood's lamp (UV-A light). [15] The differential diagnosis for tinea versicolor infection includes:[ citation needed ]
Treatments for tinea versicolor include:
This skin disease commonly affects adolescents and young adults, especially in warm and humid climates. The yeast is thought to feed on skin oils (lipids), as well as dead skin cells. Infections are more common in people who have seborrheic dermatitis, dandruff, and hyperhidrosis. [4]
Dandruff is a skin condition that mainly affects the scalp. Symptoms include flaking and sometimes mild itchiness. It can result in social or self-esteem problems. A more severe form of the condition, which includes inflammation of the skin, is known as seborrhoeic dermatitis.
Tinea cruris (TC), also known as jock itch, is a common type of contagious, superficial fungal infection of the groin and buttocks region, which occurs predominantly but not exclusively in men and in hot-humid climates.
Seborrhoeic dermatitis is a long-term skin disorder. Symptoms include flaky, scaly, greasy, and occasionally itchy and inflamed skin. Areas of the skin rich in oil-producing glands are often affected including the scalp, face, and chest. It can result in social or self-esteem problems. In babies, when the scalp is primarily involved, it is called cradle cap. Mild seborrhoeic dermatitis of the scalp may be described in lay terms as dandruff due to the dry, flaky character of the skin. However, as dandruff may refer to any dryness or scaling of the scalp, not all dandruff is seborrhoeic dermatitis. Seborrhoeic dermatitis is sometimes inaccurately referred to as seborrhoea.
Malassezia is a genus of fungi.
Ciclopirox is a medication used for the treatment of moderate onychomycosis of fingernails and toenails, and for the treatment of seborrheic dermatitis.
Cradle cap is crusty or oily scaly patches on a baby's scalp. The condition is not painful or itchy, but it can cause thick white or yellow scales that are not easy to remove. Cradle cap most commonly begins sometime in the first three months but can occur in later years. Similar symptoms in older children are more likely to be dandruff than cradle cap. The rash is often prominent around the ear, the eyebrows or the eyelids. It may appear in other locations as well, where it is called infantile seborrhoeic dermatitis. Cradle cap is just a special—and more benign—case of this condition. The exact cause of cradle cap is not known. Cradle cap is not spread from person to person. It is also not caused by poor hygiene. It is not an allergy, and it is not dangerous. Cradle cap often lasts a few months. In some children, the condition can last until age 2 or 3.
Dermatophytosis, also known as tinea and ringworm, is a fungal infection of the skin, that may affect skin, hair, and nails. Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in the area affected. Symptoms begin four to fourteen days after exposure. The types of dermatophytosis are typically named for area of the body that they affect. Multiple areas can be affected at a given time.
Onychomycosis, also known as tinea unguium, is a fungal infection of the nail. Symptoms may include white or yellow nail discoloration, thickening of the nail, and separation of the nail from the nail bed. Fingernails may be affected, but it is more common for toenails. Complications may include cellulitis of the lower leg. A number of different types of fungus can cause onychomycosis, including dermatophytes and Fusarium. Risk factors include athlete's foot, other nail diseases, exposure to someone with the condition, peripheral vascular disease, and poor immune function. The diagnosis is generally suspected based on the appearance and confirmed by laboratory testing.
Selenium disulfide, also known as selenium sulfide, is a chemical compound and medication used to treat seborrheic dermatitis, dandruff, and pityriasis versicolor. It is applied to the affected area as a lotion or shampoo. Symptoms frequently return if treatment is stopped.
Pityriasis alba is a skin condition, a type of dermatitis, commonly seen in children and young adults as dry, fine-scaled, pale patches on the face. It is self-limiting and usually only requires use of moisturizer creams.
Malassezia furfur is a species of yeast that is naturally found on the skin surfaces of humans and some other mammals. It is associated with a variety of dermatological conditions caused by fungal infections, notably seborrhoeic dermatitis and tinea versicolor. As an opportunistic pathogen, it has further been associated with dandruff, malassezia folliculitis, pityriasis versicolor (alba), and malassezia intertrigo, as well as catheter-related fungemia and pneumonia in patients receiving hematopoietic transplants.
Tinea nigra, also known as superficial phaeohyphomycosis and Tinea nigra palmaris et plantaris, is a superficial fungal infection, a type of phaeohyphomycosis rather than a tinea, that causes usually a single 1–5 cm dark brown-black, non-scaly, flat, painless patch on the palms of the hands and the soles of the feet of healthy people. There may be multiple spots. The macules occasionally extend to the fingers, toes, and nails, and may be reported on the chest, neck, or genital area. Tinea nigra infections can present with multiple macules that can be mottled or velvety in appearance, and may be oval or irregular in shape. The macules can be anywhere from a few mm to several cm in size.
Malassezia globosa is a species of yeast-like fungus.
Malassezia folliculitis or pityrosporum folliculitis, is a skin condition caused by infection by Malassezia yeast.
Postinflammatory hypopigmentation is a cutaneous condition characterized by decreased pigment in the skin following inflammation of the skin.
Malassezia pachydermatis is a zoophilic yeast in the division Basidiomycota. It was first isolated in 1925 by Fred Weidman, and it was named pachydermatis after the original sample taken from an Indian rhinoceros with severe exfoliative dermatitis. Within the genus Malassezia, M. pachydermatis is most closely related to the species M. furfur. A commensal fungus, it can be found within the microflora of healthy mammals such as humans, cats and dogs, However, it is capable of acting as an opportunistic pathogen under special circumstances and has been seen to cause skin and ear infections, most often occurring in canines.
Malassezia sympodialis is a species in the genus Malassezia. It is characterized by a pronounced lipophily, unilateral, percurrent or sympodial budding and an irregular, corrugated cell wall ultrastructure. It is one of the most common species found on the skin of healthy and diseased individuals. It is considered to be part of the skin's normal human microbiota and begins to colonize the skin of humans shortly after birth. Malassezia sympodialis, often has a symbiotic or commensal relationship with its host, but it can act as a pathogen causing a number of different skin diseases, such as atopic dermatitis.
Malassezia arunalokei is a species of yeast-like fungus that was identified as a new to science in 2016. It has been isolated from the skin of both seborrheic dermatitis patients and healthy individuals from India. A combination of several phenotypic characteristics distinguish this species from others in genus Malassezia. These include: colony morphology ; the absence of activity from the enzyme catalase; growth at 37 °C (99 °F); and the precipitation that results when grown with the chemicals Tween 20 or Cremophor EL.
Topical antifungaldrugs are used to treat fungal infections on the skin, scalp, nails, vagina or inside the mouth. These medications come as creams, gels, lotions, ointments, powders, shampoos, tinctures and sprays. Most antifungal drugs induce fungal cell death by destroying the cell wall of the fungus. These drugs inhibit the production of ergosterol, which is a fundamental component of the fungal cell membrane and wall.