and may explain the efficacy of antifungal treatment of seborrheic dermatitis In cases where systemic findings are associated with seborrhea that is new-onset, chronic, or particularly severe, workup should include evaluation for HIV, immune deficiency, or LCH Treatment depends on the sites of involvement For scalp involvement, an anti-inflammatory antifungal shampoo is appropriate: selenium sulfide, ketoconazole, or ciclopirox shampoos used daily for a week, and then maintained twice weekly is often sufficient The facial involvement can be managed with once- or twice-daily use of a topical anti-inflammatory antifungal creams such as clotrimazole or ketoconazole cream prn Occasionally, for more severe flares, brief courses of low-potency topical steroid (hydrocortisone 1% or 2.5%) or calcineurin inhibitor (pimecrolimus cream or tacrolimus ointment) can be applied twice daily for up to a week at a time on an as-needed basis As this tends to be a chronic, relapsing condition, advising appropriate follow-up is important Pityriasis rosea PR is a self-limited inflammatory skin disorder characterized by an initial larger herald patch or plaque, followed by the eruption of multiple smaller oval papules and plaques concentrated on the neck and torso areas Individual lesions often show a collarette of scale ( Fig 70.7 ) and typically follow lines of skin tension in a so-called “fir tree” or “Christmas tree” pattern The condition is most commonly seen among adolescents and adults Younger patients and those with darker skin may show atypical features with greater involvement of palms and soles, or an inverse pattern with concentrated areas in the intertriginous folds