Pityriasis versicolor

What is it pityriasis versicolor?

Pityriasis versicolor is a common yeast infection of the skin, in which scaly discolored patches appear on the chest and back.

The term pityriasis is used to describe skin conditions in which scale It looks similar to bran. The multiple colors of pityriasis versicolor give rise to the second part of the name, versicolor. Pityriasis versicolor is sometimes called tinea versicolor, although the term ringworm should be used strictly for dermatophyte fungal infections.

Who gets pityriasis versicolor?

Pityriasis versicolor most often affects young adults and is slightly more common in men than women. It can also affect children, adolescents, and older adults.

Pityriasis versicolor is more common in the heat, damp climates than in cold and dry climates. It often affects people who sweat a lot. It can disappear in the winter months and reappear every summer.

Although not considered infectious in the conventional sense, pityriasis versicolor sometimes affects more than one member of a family.

What are the clinical features of pityriasis versicolor?

Pityriasis versicolor affects the trunk, neck, and/or arms, and is rare in other parts of the body. The patches may be coppery brown, paler than the surrounding skin, or pinkish. Pale patches may be more common on dark skin; This appearance is known as pityriasis versicolor alba. Sometimes the patches start scaly and brown, and then resolve through a white, nonscaly stage.

Pityriasis versicolor is usually asymptomatic, but in some people it is mildly itchy.

In general, the pale or dark patches due to pityriasis versicolor tend to be no more or less prone to sunburn than the surrounding skin.

See more images of pityriasis versicolor.

What is the cause of pityriasis versicolor?

Pityriasis versicolor is caused by the mycelial growth of fungi of the genus Malassezia.

Malassezia are part of the microbiota (microorganisms found in normal skin). Are dependent in lipid For survival. Fourteen different species of Malassezia have been identified. The most common cultivated species of pityriasis versicolor are M globosa, M restricta, and M sympodialis.

Malassezia generally grows sparingly in the seborrheic areas (scalp, face and chest) without causing a eruption. It is not known why they grow more actively on the skin surface of patients prone to pityriasis versicolor. One theory implicates a tryptophan-dependent metabolic pathway.

Yeasts induce enlargement melanosomes (pigment granules) within basal melanocytes in the brown type of pityriasis versicolor. It is easier to demonstrate yeasts in scrapings taken from this type of pityriasis versicolor than in those taken from the white type.

the white or hypopigmented The type of pityriasis versicolor is thought to be due to a chemical produced by malassezia that spreads into the epidermis and impairs the function of melanocytes.

The pink type of pityriasis versicolor is mildly inflamed, due to dermatitis induced by malassezia or its metabolites. Pityriasis rosea versicolor and seborrheic dermatitis it can coexist, since both are associated with malassezia.

Hyperpigmented, hypopigmented and inflamed pityriasis versicolor are generally considered distinct variants, but can sometimes coexist.

How is pityriasis versicolor diagnosed?

Pityriasis versicolor is usually diagnosed clinically. However, the following tests may be helpful.

• Wooden lamp examination (black light): yellow-green fluorescence can be seen in the affected areas
• Microscopy using potassium hydroxide (KOH) to remove skin cells: hyphae and yeast cells resembling spaghetti and meatballs are seen
• Mushrooms culture—This is often said to be negative, as it is quite difficult to persuade yeasts to grow in a laboratory

• Skin biopsy– fungal elements can be seen inside the outer skin cells (stratum corneum) in histopathology. Special stains may be required.

What is the treatment for pityriasis versicolor?

Mild pityriasis versicolor is treated with current antifungal agents

• topical azole cream/ shampoo (econazole, ketoconazole)
• selenium sulfide
• Terbinafine gel
• Ciclopirox cream /solution
• Propylene glycol solution
• Sodium thiosulfate solution

The medication should be applied broadly to all affected areas at bedtime for as long as directed (usually between 3 days and about two weeks, depending on the extent of the rash).

Oral antifungal agents, itraconazole and fluconazole, are used to treat pityriasis versicolor when extensive or if topical agents have failed. Oral terbinafine, an antifungal agent used to treat dermatophyte infections, is not effective for malassezia infections such as pityriasis versicolor.

Vigorous exercise within an hour of taking the medication can help sweat it out onto the surface of the skin, where it can effectively eradicate the fungus. Bathing should be avoided for a few hours. A few days' treatment will eliminate many cases of pityriasis in the long term, or at least for several months.

Recurrences of pityriasis versicolor

Pityriasis versicolor usually resolves satisfactorily with treatment but often recurs when conditions are right for malassezia to grow. When the scaly component of pityriasis versicolor recurs, antifungal treatment should be repeated.

In those who have frequent recurrences, antifungal shampoo or oral antifungal treatment may be prescribed for one to three days per month.

Occasionally, the white marks persist long after the climbing and the yeasts are already gone despite exposure to the sun. In such cases, additional antifungal treatment is not helpful.