Psoriasis inverse

Inverse psoriasis spares the areas commonly involved in plaque psoriasis and instead appears in intertriginous areas, where scaling is minimal. 

Inverse psoriasis is similar to plaque psoriasis, although the reddened skin areas are not associated with a scaly plaque. It is associated with skin folds and in moist areas, including the axillae, beneath the breasts, groin and in skin... 

A 74-year-old woman developed inverse psoriasis after 14 days of therapy with terbinafine 250 mg/day for onychomycosis (53). The lesions resolved almost completely on withdrawal of terbinafine and topical therapy. 

Probable psoriatic onychodystrophy, misdiagnosed as onychomycosis and treated with terbinafine, induced inverse psoriasis in the second case, underscoring the importance of mycological confirmation of onychomycosis before therapy. 

Pauluzzi P, Boccucci N. Inverse psoriasis induced by terbinafine. Acta Derm Venereol 1999 79(5) 389. 

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