Discoloration worsens following sun exposure - Clinical Advisor

Discoloration worsens following sun exposure

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  • Tinea Versicolor_0313 Derm Clinic 1

A man, aged 34 years, was concerned about numerous white spots on his arms and chest. He first noticed the discoloration in midsummer. As his skin became more tanned, the color difference progressively worsened.

No similar lesions were noted elsewhere. The patient reported a history of frequent sun exposure. He has no significant medical history and does not take any medications. Physical examination revealed numerous scaly hypopigmented macules on the bilateral upper and lower arms and mild involvement of the chest.



HOW TO TAKE THE POST-TEST: This Clinical Advisor CME activity consists of 3 articles. To obtain credit, you must also read Arm ulcer on a Latin American immigrant and Plaques on the lower extremities.

Tinea versicolor, also known as pityriasis versicolor, is a very common skin infection that is caused by the yeast Malassezia furfur. The condition presents with hypopigmented pink or hyperpigmented scaly nummular macules. The individual macules may coalesce into larger scaly...

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Tinea versicolor, also known as pityriasis versicolor, is a very common skin infection that is caused by the yeast Malassezia furfur. The condition presents with hypopigmented pink or hyperpigmented scaly nummular macules. The individual macules may coalesce into larger scaly plaques. These plaques are most frequently located on the chest, upper abdomen, shoulders, back, and upper arms.

Other oily areas of the skin also commonly affected include the pubis, neck, and intertriginous areas. Rarely, and usually in immunocompromised patients, tinea versicolor may present on the scalp, genitalia, palms, and soles.1

Although most patients with tinea versicolor are asymptomatic, some complain of mild to moderate itching. The most frequent associated complaints are generally of a cosmetic nature, particularly during the summer months when patients are concerned about their appearance while wearing swimsuits.

The pigment changes associated with tinea versicolor result from the yeast’s production of dicarboxylic acid, which inhibits the enzyme tyrosinase necessary for melanin production. Even after successful treatment and eradication of the yeast, the pigment changes may persist for several months until the affected areas regain pigmentation or until the postinflammatory hyperpigmentation slowly resolves.

When tinea versicolor presents in the classic locations, the diagnosis is relatively simple and requires no further testing. In atypical cases, a skin scraping or even a biopsy may be necessary to confirm the diagnosis. On microscopic examination, fungal hyphae and various-sized spores will be observed in the stratum corneum. This combination is frequently referred to as the “spaghetti and meatballs” presentation.

Tinea versicolor tends to be a chronic and recurrent condition, frequently reappearing in warm-weather months. Patients who have seborrheic dermatitis or hyperhidrosis are more frequently affected, as are those living in a tropical environment.

The differential diagnoses include pityriasis rosea, seborrheic dermatitis, lupus, syphilis, and pityriasis rubra pilaris. In the hypopigmented variant, mycosis fungoides and vitiligo should be ruled out.

Several topical treatment therapies for tinea versicolor exist. Selenium sulfide applied daily to the affected areas and then rinsed after 10 minutes is an inexpensive option. Selenium sulfide is also effective in a single overnight application. In addition, imidazoles, triazoles, ciclopirox (Penlac), zinc pyrithione, salicylic acid, and benzoyl peroxide can be used topically. The challenge is in finding the appropriate vehicle for application over a large area. Many patients find the foam vehicle easiest to use. Oral itraconazole (Onmel, Sporanox) and fluconazole (Diflucan) have also proven effective.2

Although the treatment of tinea versicolor is relatively simple, reducing the high frequency of recurrences can be challenging. Patients should be informed that recurrences are common and that prophylactic treatment is often necessary. Shampooing the affected areas weekly or monthly with shampoos containing selenium sulfide (e.g., Selsun Blue), ketoconazole, or zinc pyrithione (e.g. Head and Shoulders) is simple and effective. Monthly treatment with oral itraconazole or flucanozlae can also be considered in resistant cases.3

The man in this case was treated with topical ketoconazole (Extina, Nizoral, Xolegel) b.i.d. for two weeks. Three weeks later, he reported complete clearance of the lesions.

Esther Stern, NP, is a family nurse practitioner at Advanced Dermatology & Skin Surgery, P.C., in Lakewood, N.J.

References

  1. James WD, Berger TB, Elston DM. Andrews’ Diseases of the Skin: Clinical Dermatology. 11th ed. Philadelphia, Pa.: Saunders-Elsevier; 2011:313.
  2. Muhammad N, Kamal M, Islam T, et al. A study to evaluate the efficacy and safety of oral fluconazole in the treatment of tinea versicolor. Mymensingh Med J. 2009;18:31-35.
  3. Faergemann J, Gupta AK, Al Mofadi A, et al. Efficacy of itraconazole in the prophylactic treatment of pityriasis (tinea) versicolor. Arch Dermatol. 2002;138:69-73.

All electronic documents accessed February 27, 2013.

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