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Notes: Background  T-cell infiltration in plaque psoriasis has recently been an important subject of investigation. Interestingly, comparative analyses of the disease-specific composition of the lesional T-cell infiltrate in plaque psoriasis and other inflammatory dermatoses have only sparsely been performed.Objectives  To compare plaque psoriasis vs. atopic dermatitis and lichen ruber planus with respect to T-cell subsets, epidermal proliferation and keratinization.Patients and methods  Biopsies were taken from untreated lesional skin of patients, six with psoriasis, six with atopic dermatitis and six with lichen planus. T-cell subsets (CD4+, CD8+, CD45RO+, CD45RA+, CD2+, CD25+), an epidermal proliferation (Ki-67) and a keratinization marker (K10) were stained immunohistochemically and quantified using image analysis.Results  The high number of CD8+ T cells (52 ± 13 cells mm−1) found in the psoriatic epidermis was not found in the epidermis of atopic dermatitis (9 ± 4), nor in the epidermis of lichen planus (34 ± 10). The other T-cell subsets in the epidermis and dermis showed no statistically significant differences between psoriasis and atopic dermatitis. In contrast to the limited presence of CD4+, CD8+ and CD2+ in the psoriatic dermis (110 ± 19, 27 ± 9, 127 ± 41, cells mm−1, respectively), more impressive numbers of these cells were observed in the dermis of lichen planus (300 ± 53, 144 ± 38, 272 ± 48, respectively). CD45RO+ memory effector T-cell counts were significantly higher in the epidermis of lichen planus (39 ± 10) than in psoriasis (19 ± 5). Psoriatic epidermis proved to have major keratinocyte hyperproliferation (247 ± 26 cells mm−1 lamina basalis), as compared with atopic dermatitis (134 ± 15) and lichen planus (128 ± 20). Furthermore, a marked decreased expression of keratin 10 was observed in psoriasis (41% of epidermal area) contrary to atopic dermatitis (70%).Conclusions  Psoriatic epidermis exhibits a pronounced CD8+ epidermotropism with accompanying epidermal hyperproliferation and abnormal keratinization, which changes are only minimally expressed in atopic dermatitis and lichen planus. In plaque psoriasis, substantially fewer activated CD4+ and CD8+ T cells in the dermis and less CD45RO+ T cells in the epidermis are present in comparison with lichen ruber planus.

Notes: Background A new natural product for the treatment of psoriasis has recently become available in many European countries: Mirak. The Mirak Home Care Packs consist of natural spring water, volcanic earth and vitamin E cream. Recently, the efficacy of Mirak has come into question. As this treatment is used by many psoriasis patients in Europe, it is important for dermatologists to be informed about the clinical effects of the therapy.Aim To evaluate the efficacy and side effects of the Mirak Home Care Packs.Methods By means of a placebo-controlled left/right comparison, both clinical and histological parameters were evaluated during 6 weeks of treatment.Results The reduction in induration was significantly greater in the Mirak-treated lesions than in the lesions treated with a placebo. A reduction in desquamation was found in both treatments; the difference between the treatments was not statistically significant. A decrease in number of proliferative cells in the Mirak-treated lesions was seen, but the difference with placebo-treated lesions was not significant. The other investigated parameters did not change during treatment. No side effects were seen.Conclusions The Mirak Home Care Pack induces a modest therapeutic effect compared to placebo treatment, without significant side effects. Treatment with the Mirak Home Care Packs alone will probably not be able to compete with the already existing treatments for psoriasis.