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Notes: Purpuras include a wide spectrum of cutaneous disorders characterized by extravasation of red blood cells into the skin with consequent release of hemoglobin. Various other pigments deriving from heme are subsequently found into the skin within 2-3 weeks, accounting for the color changes (purple, orange, brown, yellowish, green-blue) which may occur in most purpuric lesions. Too often the factors leading to these disturbances are obscure. Sometimes they are obscure mainly to the dermato-venereologist as they are generally considered more pertinent to the field of interest of other specialists, i.e. in hematology or internal medicine. The dermato-venereologist should be familiar with these cutaneous conditions and, when necessary, cooperate with the hematologist in order to evaluate the cutaneous and extracutaneous signs and symptoms and to schedule the proper systemic and/or topical therapies.Learning objective At the conclusion of this learning activity, participants should be able to discuss the clinical and histological presentations of purpuric disorders and know which tests should be done to allow proper diagnosis and treatment. The participants should also be aware of the controversies concerning the pathogenesis of some kinds of purpuras (i.e. palpable purpuras), of the evolution of terminology and finally of the different therapeutic options and regimens.

Notes: Background. Progressive pigmented purpura (Schamberg's disease), a form of purpura pigmentosa chronica, is a lymphocytic capillaritis of unknown etiology and obscure pathogenesis. Our purpose was to assess the expression of cell membrane antigens (CD3, CD4, CD1a, CD36), of adhesion receptors (leukocyte function adhesion 1, LFA-1, endothelial leukocyte adhesion molecule 1, ELAM-1) intercellular adhesion molecule 1, ICAM-1), and the intercellular relationships in the early phase of the disease. Methods. Quantitative immunohistochemistry and electron-microscopy were performed on specimens of five subjects, aged 45 to 63 years. These studies were repeated in two patients after treatment with topical corticosteroid (betamethasone valerate cream 0.1%) and psoralen-ultraviolet A (puva). Results. The infiltrate consisted mainly of CD4+ lymphocytes and CD1a+ dendritic cells. Electron-microscopic investigation showed typical lymphocytes and two distinct types of dendritic cells. In the very early phase of the disease the adhesion receptors LFA-i and ICAM-1 were expressed intensely by all infiltrating cells; the adhesion receptors icam-1 and ELAM-i were expressed by endothelial cells. Close contact occured between lymphocytes and dendritic cells. After PUVA (120 J per cm2) and topical steroid therapy the infiltrate disappeared completely. Conclusions. These data suggest that a cell-mediated immune mechanism may be important in progressive pigmented purpura and that the early endothelial expression

Notes: General description The mycobacteria are a large genus which includes important pathogens of man and other vertebrates, apparently harmless commensals, and free-living saprophytes. The relative importance of non-tuberculous mycobacterial diseases has been undergoing evolution during the past few years and further changes and modifications are expected to occur in the near future. In this paper we review the microbiological, clinical, histological and therapeutical aspects of the most important human pathogens of non–tuberculous mycobacteria.Learning objective At the conclusion of this learning activity, participants should be able to describe the pathogenesis. the microbiological, clinical and histological features of non-tuberculous mycobacterial skin infections and should be able to diagnose and treat these skin diseases.

Notes: Background. Adhesion molecules play a major role in the pathogenesis of inflammatory skin diseases by regulating lymphocyte trafficking and homing in an inflamed area. Methods. The expression of the lymphocyte function-associated antigen-1 (LFA-1) and of its ligand, the intercellular adhesion molecule-1 (ICAM-I) has been studied in psoriatic skin lesions of 10 patients with guttate, nummular, and palmoplantar psoriasis. In addition, the peculiar immunophenotype of infiltrating cells (CD3, CD4, CD8, CD25) and their correlation with HLA-DR expression before and after treatment with oral cetirizine, a highly selective, third generation H1-receptor antagonist has been examined using the labeled avidin biotin (LAB) system. Results. Cetirizine treatment modulated in vivo the expression of adhesion molecules LFA-I/ICAM-1 as shown in all cases by decreased levels of their expression on keratinocytes and on dermal endothelial cells (P 〈 0.001). The expression of HLA-DR on keratinocytes and endothelial cells was also inhibited after treatment. The numbers of infiltrating CD3–, CD4–, CD8–positive cells were reduced, whereas there was no significant modification of CD25–positive cells within the epidermis and the dermis. Conclusion. This open clinical trial suggests that cetirizine could be effective in treating psoriasis: (1) for its symptomatic control on itching; (2) for its immunopharmacologic modulation of leukocyte integrins and on the immunophenotype pattern of infiltrating and resident cells, and (3) for contributing to the clearing of the lesions clinically.

Notes: Abstract Originally described as a product of the pituitary gland, propiomelanocortin (POMC) has recently been identified in other tissues, such as in human skin, where it may accumulate in response to various stimuli. Thus far, epidermal keratinocytes, as well as melanocytes and macrophages, have been shown to express POMC. This study investigated the expression of POMC mRNA in cultured dermal fibroblasts derived from either normal skin or keloids. Using Northern blot hybridization with a POMC cDNA generated by RT-PCR of mRNA isolated from cardiac muscle, we demonstrated that dermal fibroblasts express POMC, as significant levels of mRNA were detected in unstimulated cells in culture. POMC transcript steady-state levels were strongly reduced by transforming growth factor-β (TGF-β). whereas tumor necrosis factor-α (TNF-α) counteracted the effect of TGF-β and exerted a stimulatory activity on POMC mRNA levels. Reduction of POMC transcript levels by TGF-β was also observed in cultured keratinocytes. Clearly detectable levels of POMC mRNA were detected in cultured keloid-derived fibroblasts; however, little, if any, regulation by TGF-β was observed. These data represent the first demonstration of POMC expression by fibroblasts and down-regulation by TGF-β. Furthermore, our results indicate altered TGF-β regulation of POMC gene expression in keloid-derived fibroblasts suggesting that POMC may play a role in the pathogenesis of keloid formation.

Notes: An 84-year-old white woman presented with diagnosed vascular failure in the left leg. The patient had had diabetes mellitus for over 50 years. Five years earlier, her right leg was amputated because of an obliterating arteriopathy.At the time of hospitalization, she showed dry gangrene in all the toes on her left foot. A laser Doppler test performed on the left leg showed severe peripheral arteriopathy affecting the anterior and posterior tibial arteries, with a Windsor index of 20% in her ankle.On physical examination, the patient showed several nodular lesions on the anterior and anterior-medial surface of her left leg. These lesions were infiltrated, of a hard elastic consistency, and occasionally confluent, with a diameter ranging from 0.5 to 4 cm (Fig. 1) and the color varying from ochre-yellow to brownish-red to slate-brown. The patient reported that these lesions had erupted approximately 2 years earlier and had been accompanied by itching and mild burning. She had shown them to her family doctor who had diagnosed seborrhoeic keratosis.A series of biopsies performed on the nodules revealed the presence of atypical melanocytes arranged in alveolar formations that reached the epidermis. The epidermis appeared thin, compressed, and atrophic; no signs of junctional activity could be seen (Fig. 2).The tumor cells were round, with a clear cytoplasm and atypical, hyperchromatic, oval nuclei containing nucleoli (Fig. 3). Some atypical melanocytes contained small amounts of melanic pigment that was concentrated in the cytoplasm of macrophages which were mixed with the elements of the tumor. There had been no melanoma in the clinical history of the patient.The patient had a chest roentgenogram with tomography and a computer tomography (CT) scan of the liver, spleen, mediastinum, and brain, all with negative results.The case is worth reporting because of the peculiar cutaneous lesions that could suggest several diagnostic hypotheses. The clinical picture could have been interpreted as being Kaposi's sarcoma, seborrhoeic keratosis, angiosarcoma, or multiple Spitz nevi. A Spitz nevus is a benign variant of a compound nevus that is characterized histopathologically by atypical, large melanocytes with abundant eosinophilic cytoplasm and large vesicular nuclei with prominent nucleoli. Histologic examination removed any doubt, suggesting a metastatic origin for the proliferating nodules. Marked expression of S-100 protein and of HMP45 was found by immunohistochemistry; HMP45 was also intensely positive in the deep layers of the dermis.It was not possible to define the site of the primary lesion from the patient's history or from physical examination;1,2 however, one cannot exclude that the primary lesion was at the same site as where the metastases had diffused, either by growing spontaneously from healthy tissue or through a transformation of anevus.3,4