Bacterial flora in psoriasis

Abstract

The aerobic bacterial flora of psoriatic plaques, uninvolved skin and the anterior nares of forty psoriatic patients was studied. The incidence od Staphylococcus aureus was 30% in the anterior nares, 20% on the plaques and 13% on the uninvolved skin. S. aureus counts were 3 x 10(2)/cm2 on the plaques and 1-5 x 10/cm2 on the normal skin. The total bacterial counts were also higher on plaques (7-9 x 10(3)/cm2) than on normal skin (3-0 x 10(3)/cm2). The incidence of lipophilic diphtheroids was significantly lower on the plaques (4%) than the normal skin (30%). Eighty percent of the strains of S. aureus isolated from psoriatic patients were resistant to 10 units of penicillin. Because of increased desquamation, psoriatic skin is a public health hazard.