Larisa Prpić Massari

Perforin expression is upregulated in the epidermis of psoriatic lesions.

Background  There are currently very few data regarding the role of cell‐mediated cytotoxicity in psoriasis. Both cytotoxic T lymphocytes and natural killer (NK) cells mediate cytotoxicity reactions, mainly by two distinct pathways, the perforin/granzyme and the Fas/Fas ligand pathway.

The role of perforin-mediated apoptosis in lichen planus lesions

Lichen planus is recognized as a T-cell-mediated disease. Histologically, it is characterized by the formation of colloid bodies representing apoptotic keratinocytes. The apoptotic process mediated by CD8+ cytotoxic T lymphocytes (CTLs) and NK cells mainly involves two distinct pathways: the perforin/granzyme pathway and the Fas/FasL pathway. So far, little is known regarding the role of perforin-mediated apoptosis in lichen planus. In the present study, the expression and distribution of perforin, T and NK cell subsets in the epidermis and dermis of lesional and nonlesional lichen planus skin were studied. Skin biopsy specimens from lesional and nonlesional skin of ten patients with lichen planus and eight healthy persons were analysed by immunohistochemistry. Significant accumulation of T cells, particularly of CD4+ and CD8+ subsets, was found in both epidermis and dermis of lichen planus lesions compared with nonlesional and healthy skin. There were no significant differences in the incidence of NK cells (CD16+ and CD56+) between lesional, nonlesional and healthy skin. Perforin expression was significantly upregulated in the epidermis of lichen planus lesions. In conclusion, accumulation of perforin+ cells in the epidermis of lichen planus lesions suggest a potential role of perforin in the apoptosis of basal keratinocytes.

Tinea incognito due to Microsporum canis in a 76-year-old woman

A 76 year old female patient presented with multiple erythematous itchy patches on her face and neck along with hair loss, scaling and inflammation in the occipital region of the scalp that had started 2 months ago. Therapy with local corticosteroid creams were recommended. Direct microscopy of scraping specimens from skin lesions and scalp were positive for fungal hyphae. The patient was successfully treated with oral itraconazol and for 3 months and 1 % clotrimazole cream.