​Dermatology - Pityriasis Versicolor

​Dermatology - Pityriasis Versicolor
Pityriasis versicolor, also known as tinea versicolor in the United States, is caused by the excessive growth of Malassezia furfur, a yeast that often lives in the keratin of the skin and hair follicles of individuals who have reached puberty and beyond. The infection is not easily transmitted from person to person. It arises when there is an excessive development of the normal bacteria that live on the skin, in the presence of wet skin and excessive sweating.

Although lesions often do not cause any symptoms, patients may have aesthetic concerns regarding dyspigmentation.
Chronic lesions persisting for extended periods of time.
Abnormalities
Macules are well-defined, circular or oval-shaped, pink to brown spots that come in different sizes. They have a fine layer of scaling that can be best observed by gently rubbing the affected area. Lesions that have been treated or resolved do not have any scale. Lesions have the potential to increase in size and combine, resulting in the formation of huge geographic areas.

The diagnosis is made through direct microscopic inspection using potassium hydroxide (KOH). The differential diagnosis comprises vitiligo, pityriasis alba, postinflammatory hypopigmentation, tinea corporis, seborrheic dermatitis, and cutaneous T cell lymphoma.


Topical medications for treatment consist of selenium sulfide (2.5%) lotion or shampoo, ketoconazole shampoo, azole creams (ketoconazole, econazole, micronazole, clotrimazole), or terbinafine 1% solution. Systemic therapy comprises the administration of ketoconazole 400 mg, fluconazole 400 mg, or itraconazole 400 mg, with ketoconazole being taken one hour before to exercise.