Makindo Medical Notes.com

Related Subjects: |Nikolsky's sign |Koebner phenomenon |Erythema Multiforme |Pyoderma gangrenosum |Erythema Nodosum |Dermatitis Herpetiformis |Lichen Planus |Acanthosis Nigricans |Acne Rosacea |Acne Vulgaris |Alopecia |Vitiligo |Urticaria |Basal Cell Carcinoma |Malignant Melanoma |Squamous Cell Carcinoma |Mycosis Fungoides (Sezary Syndrome) |Xeroderma pigmentosum |Bullous Pemphigoid |Pemphigus Vulgaris |Seborrheic Dermatitis |Pityriasis/Tinea versicolor infections |Pityriasis rosea |Scabies |Dermatomyositis |Toxic Epidermal Necrolysis |Stevens-Johnson Syndrome |Atopic Eczema/Atopic Dermatitis |Psoriasis

About

• Tends to be seen in adolescents and young adults and related to a warm humid environment.
• It is a disorder of the healthy but the immunocompromised are at risk.
• Both were previously called Malassezia Furfur.

Aetiology

• Due to Pityrosporum orbiculare (round form) and Pityrosporum ovale (oval form).
• The organism responsible thrives on free fatty acids and triglycerides
• The fungus affects the melanocytes hence the hypo- pigmentation.

Clinical

• Often unnoticed and may in some be mildly itchy
• Multiple small, circular macules of various colours (white, pink, or brown)
• Those individuals with oily skin, may be more susceptible. Also, those who are immunosuppressed
• This happens most often in warm moist climates. Most people with this condition are perfectly well and healthy.
• Rash fails to tan and so stays paler than the surrounding skin so often noticed for the first time after a sunny holiday.

Investigations

• Ultra-violet light lamp known as Wood's lamp on the skin to check for the typical yellow fluorescence of pityriasis Versicolor.
• Skin scrapings can be looked at under the microscope to see if yeasts are present.
• Skin test (biopsy) may be necessary.

Management

• The rash clears with treatment though the pale areas will take a few months to get back to their normal colour. Pityriasis versicolor does not leave scars.
• Griseofulvin is not effective. Ketoconazole 2% shampoo, used as a single application or daily for 3 days, is highly effective and is the treatment of the first choice. Apply the shampoo to the entire skin surface from the lower posterior scalp area down to the thighs. The shampoo is left in place for 5 minutes and then rinsed thoroughly. Wash the scalp with shampoo at the same time.
• Other treatment is topical selenium sulphide.
• For recurrence consider Itraconazole 200 mg qd for 7 days provided an 89% mycologic cure rate at the end of 4 weeks. They work well but are usually kept in reserve for widespread rashes, or those that have not got better with treatment put on the skin.
• Recurrences: Often comes back. Using a medicated shampoo as a bodywash to the trunk from time to time, over several months, cuts down this risk. If the area affected is small, Ketoconazole or clotrimazole cream can be applied twice daily. Remember that the pale areas left after treatment may take several months to get back to their normal colour. This cannot be speeded up.