No abstract

MR is a unique histiocytic proliferative disease with a peculiar immunophenotypic pattern and distinctive clinical and histopathological aspects.

Sporotrichosis is a deep fungal disease caused by a dimorphic fungus, Sporothrix schenckii. It occurs more frequently in the tropical and subtropical areas and is mainly characterized by nodular lesions of cutaneous and subcutaneous tissues and adjacent lymphatics that suppurate and ulcerate. Infection occurs by manipulation of contaminated soil, cats, or some wild animals or by inhalation of spores. Itraconazole is the best drug for treatment of sporotrichosis.

Paracoccidioidomycosis is a fungal infection that is relatively common in Brazil, Venezuela, Colombia, Ecuador, and Argentina. Sporadic cases can also be seen in some other countries. It is caused by a dimorphic fungus, Paracoccidioides brasiliensis, which affects mainly the skin, lymph nodes, lungs, and oral, nasal, and gastrointestinal mucous membranes. Depending on the specific immunity of the host, the infection can assume many forms and affect single or multiple organs, eventually becoming a severe and even fatal disease. It is very important for dermatologists of all over the world to know about paracoccidioidomycosis because sometimes the disease only manifests many years after the individual has left the endemic area.

Oral lichen planus (OLP) is a common T cell-mediated mucocutaneous disease of unknown etiology. A great number of factors have been suggested as relevant to the etiology of this disease. In this article, the authors assemble recent knowledge about the pathogenesis of OLP, discuss some proposed hypotheses, and compare OLP with oral lichenoid lesions.

Dermoscopy is a very useful technique for the analysis of pigmented skin lesions. It represents a link between clinical and histological views, permitting an earlier diagnosis of skin melanoma. It also helps in the diagnosis of many other pigmented skin lesions, such as seborrheic keratosis, pigmented basal cell carcinoma, hemangioma, blue nevus, atypical nevus, and mole, which can often clinically simulate melanoma. In this article, dermoscopy is reviewed from its history to the basic concepts of the interpretation of dermoscopic images. The goal is to introduce this subject to those not yet familiar with it, in order to instigate and encourage the training and practice of this technique of growing importance for everyday usage.

Although dermal collagens appear increased in hypertrophic scars, this was not tested in tissue samples using objective methods. We compared the expression of types I and III collagen in hypertrophic and non-hypertrophic scars, at 6–12 and 18–24 months after burn using a quantitative method. Among 17 patients with extensive burns, 3 patients had acute scars, 8 had hypertrophic or non-hypertrophic scars at 6–12 months after burn, and 6 had hypertrophic or non-hypertrophic scars at 18–24 months after burn. After clinical assessment of scars using the Vancouver Scale, immunohistochemistry for types I and III collagens was performed. Images were captured with a laser scanning confocal microscope and the relative amounts of types I and III collagens were determined in superficial and deep dermis. The effects of time and scar type were assessed using two way ANOVA and Tukey’s test. Collagen III scar/normal ratios were higher in hypertrophic scars at both time points (p=0.05). There were no differences in collagen I scar/normal ratios. Large variation was observed in scars during the acute phase regarding the expression of collagens. Easily accessed by immunohistochemistry and confocal microscopy, type III collagen deposition may help in determining scar phenotype, differentiating hypertrophic and non-hypertrophic scars.

Paraneoplasias are frequently the first sign of a subjacent malignant tumor. Although relatively rare, they need to be recognized by dermatologists to make an early diagnosis and improve the prognosis related especially to the neoplasia. This contribution presents the morphologic aspects and the differential diagnosis of the main paraneoplasias, which include acanthosis nigricans, tripe palms, Leser-Trélat sign, acquired ichthyosis, acquired hypertrichosis lanuginosa, pityriasis rotunda, erythema gyratum repens, palmo-plantar keratoderma, Bazex syndrome, and dermatomyositis, hoping to contribute to the familiarity of dermatologists with the identification and early diagnosis of this group.