Epidermal dendritic S100 positive cells in necrobiosis lipoidica and granuloma annulare

Langerhans cells in cutaneous tumours: immunohistochemistry study using a computer image analysis system

Immunohistochemistry, based on antibody anti-S100 protein, was used to evaluate the Langerhans cells (LC) in benign and malign skin neoplasias. These cells were quantitatively estimated using a computer image analysis (OPTIMAS software system, Version 6.1) in skin biopsies diagnosed as basal cell carcinoma (BCC), epidermoid carcinoma (EpC), trichoepithelioma (TE), keratoacanthoma (KA), seborreic keratosis (SK) and actinic keratosis (AK). The antibody anti-S100 protein recognized them. No significant variations were observed in the number of LC among malignant tumour (BCC = 23.25 +/- 5.81 and EpC = 20.88 +/- 4.24). Benign lesions (AK = 33.04 +/- 7.11; TE = 55.74 +/- 9.35; SK = 42.38 +/- 9.92, and KA = 47.62 +/- 10.4) presented a higher number of LC when they were compared among them and to malignant and normal tissues. No significant differences were observed in LC area and volume between benign and malign neoplasias. These results indicate possibly differences in the immunogenicity between benign and malign epidermic tumours. In conclusion, the experimental computer assessment method was reliable and consistent to morphometric analysis of tumoural tissues.

Tattooing increases the number of Langerhans cells in skin: an immunocytochemical study

Tattooing is an act of permanent marking of the skin with indelible patterns by pricking and inserting pigments. Langerhans cells (LCS) are dendritic cells normally present in suprabasal layers of the epidermis of the skin. To assess whether there were any effects caused by the tattooing on Langerhans cell population and cutaneous nerves, skin from affected areas (n = 15) was compared with controls (n = 10). Frozen sections were immunostained with antisera to S-100. No discernible change either in distribution or in number of Langerhans cells and nerves was seen upon comparison with control skin taken from different areas, but all of the specimens taken from affected areas had a significant increase in the number of Langerhans cells (p < 0.001) even after several years of tattooing with no change in the cutaneous nerves. Thus, the study shows persistent stimulation of Langerhans cell population in tattooed skin.

A case of necrobiosis lipoidica treated with systemic corticosteroid

A 43-year-old woman had asymptomatic eruptions on the anterior sides of both legs for 5 years. Biopsy specimens revealed the typical findings of necrobiosis lipoidica. An immunofluorescence study demonstrated no deposits of immunoglobulins, complement, or fibrinogen in vessel walls. Immunohistochemical staining revealed CD4 positive lymphocytes dominating in the lesion and strong expression of ICAM-1 on the endothelial cells, giant cells, lymphocytes and dermal fibroblasts in the lesion. The eruptions resolved remarkably with oral corticosteroid therapy.

Association of generalized granuloma annulare with autoantibodies

Granuloma annulare is a degenerative disease of the skin histopathologically characterized by focal degeneration of collagen with a surrounding infiltrate of lymphoid cells, histiocytic cells, and multinucleated giant cells. Immunological abnormalities such as delayed-type hypersensitivity and vasculitic origin are suspected in the pathogenesis. We describe three patients with generalized granuloma annulare, in whom autoantibodies, including antinuclear antibody, antithyroid stimulating hormone receptor antibody, and immune complex, were detected.

Necrobiosis lipoidica: treatment with systemic corticosteroids

In an attempt to find an effective therapy for necrobiosis lipoidica, we have treated six patients with this disease with a 5-week course of systemic corticosteroids. This treatment resulted in complete cessation of disease activity in all patients and no recurrence in a mean follow-up period of 7 months; however, restitution of atrophic skin lesions could not be achieved. The therapy was well tolerated and did not pose problems, even in diabetic patients. These results strongly suggest that short-course therapy of necrobiosis lipoidica with corticosteroids is of lasting benefit to these patients and should probably be considered early in the course of their skin disease.

Familial non-diabetic necrobiosis lipoidica

Necrobiosis lipoidica (NL) is a cutaneous disorder with distinctive clinical and morphologic characteristics. It is associated with diabetes mellitus in two thirds of cases. The aetiology and pathogenesis of NL are unknown but familial cases of NL seem to be extremely rare. We report the occurrence of NL in two sisters with normal glucose tolerance.