[Tinea capitis: new insights into an old disease]. / Tinea capitis: actualité d'une pathologie ancienne.

Tinea capitis is a superficial dermatophytic infection of the scalp. This common dermatosis occurs predominantly in children. The clinical manifestation of the disease is heterogeneous, and vary widely depending on the pathogenic fungal agent. Direct mycological examination and cultures are mandatory for an accurate diagnosis and species identification. Treatment should be both local and systemic, and ideally is tailored to the dermatophytic species identified by the laboratory diagnostic work up. Secondary prophylaxis through supplementary measures is crucial to avoid epidemic outbreak and patient reinfection.

Tinea capitis (ou teigne du cuir chevelu) est une infection fongique superficielle du cuir chevelu par un dermatophyte. Cette dermatose est fréquente et prédomine en population pédiatrique. Le tableau clinique est hétérogène et varie beaucoup en fonction de l'espèce de dermatophyte associée. L'examen mycologique direct et des cultures doivent être effectués pour un diagnostic précis et une identification de l'espèce. Le traitement devrait être à la fois local et systémique, et adapté au diagnostic de l'espèce dermatophyte identifiée en laboratoire de mycologie. La prophylaxie secondaire, par des mesures associées, est déterminante pour limiter l'émergence de foyers épidémiques ou la réinfection du patient.

[Sweat as an indicator of health]. / La sueur comme indicateur de la santé.

Sweat is a body fluid produced by the sweat glands and is mainly composed of water. Sweat has various functions, the two main ones being the evacuation of heat produced by the body, especially during exercise, and the maintenance of skin homeostasis. Its production is highly variable and depends on many individual and environmental factors. Various diseases or conditions affect its proper functioning. This article presents an overview of the characteristics, the main health issues, and the current and potential applications related to sweat.

La sueur est un fluide corporel produit par les glandes sudoripares et composé principalement d'eau. La transpiration remplit diverses fonctions, dont les principales sont l'évacuation de la chaleur produite par l'organisme, en particulier durant l'effort physique, et le maintien de l'homéostasie de la peau. Sa production est très variable quantitativement et qualitativement et dépend de multiples facteurs individuels et environnementaux. Différentes pathologies ou conditions altèrent son bon fonctionnement. Cet article présente un aperçu des caractéristiques, des principaux problèmes de santé et des applications actuelles et potentielles en lien avec la sueur.

[Sports dermatology]. / Dans la peau des sportif·ve·s: dermatologie du sport.

Athlete's skin is under great stress and its integrity is essential. Knowledge and prevention of sports-related dermatoses are fundamental to athlete's the management. Hereby we review common sport-related affections classified by their etiologies (traumatic, infectious, inflammatory and environmental dermatoses).

La peau est soumise à des contraintes importantes lors des activités sportives et son intégrité est essentielle mais souvent banalisée. La connaissance et la prévention des dermatoses liées aux différents sports sont fondamentales pour une prise en charge optimale. Cet article rappelle les diverses dermatoses liées au sport classées par étiologies (traumatiques, infectieuses, inflammatoires et liées à l'environnement).

[Nail alterations in children]. / Altérations unguéales de l'enfant.

Alterations of the nail unit in children may be congenital or acquired, may be an isolated finding or part of a systemic problem or a syndrome. In this article we describe the most common childhood nail changes and underscore some important clinical clues that should motivate further investigations. Moreover we give a brief overview of the management of these nail pathologies.

Parmi les atteintes unguéales chez l'enfant, on différencie les atteintes congénitales des acquises et les affections isolées des manifestations témoignant d'une possible atteinte systémique ou syndromique. Le but de cet article est de revoir les atteintes unguéales pédiatriques les plus couramment observées et de souligner les signes unguéaux nécessitant des investigations plus approfondies. De plus, un bref aperçu de la prise en charge de ces différentes atteintes unguéales est donné.

Skin Colonization by Staphylococcus aureus Precedes the Clinical Diagnosis of Atopic Dermatitis in Infancy.

Atopic dermatitis (AD) has a well-established association with skin colonization or infection by Staphylococcus aureus, which can exacerbate the disease. However, a causal relationship between specific changes in skin colonization during the first years of life and AD development still remains unclear. In this prospective birth cohort study, we aimed to characterize the association between skin colonization and AD development in 149 white infants with or without a family history of atopy. We assessed infants clinically and collected axillary and antecubital fossa skin swabs for culture-based analysis at birth and at seven time points over the first 2 years of life. We found that at age 3 months, S. aureus was more prevalent on the skin of infants who developed AD later on. S. aureus prevalence was increased on infants' skin at the time of AD onset and also 2 months before it, when compared with age-matched, unaffected infants. Furthermore, at AD onset, infants testing positive for S. aureus were younger than uncolonized subjects. In conclusion, our results suggest that specific changes in early-life skin colonization may actively contribute to clinical AD onset in infancy.

[Reflectance confocal microscopy : what future for dermatology ?] / Microscopie confocale in vivo : quel avenir en dermatologie ?

Reflectance confocal microscopy is a non invasive imaging technique which provides in vivo and real time images of different skin tissues with a resolution close to histology, however with a depth limited to superficial dermis.The first lesions that were morphologically analyzed are melanocytic lesions. Reflectance confocal microscopy has been used for about ten years in dermatology. Its progressive improvement over the years has allowed it to be an efficient tool for diagnosing cutaneous tumors. It has been developed for inflammatory dermatosis, cutaneous infections, angiomas, cosmetology. Furthermore, it is also used to delimit the edges of lesions or the area to biopsy. This cutaneous imaging technique represents a major innovation and has its place in dermatological practice.

La microscopie confocale (MC) par réflectance est une technique d'imagerie non invasive qui permet d'obtenir in vivo et en temps réel des images de différents tissus de la peau avec une résolution proche de l'histologie, avec toutefois une profondeur limitée au derme superficiel.Les premières lésions qui ont été analysées morphologiquement sont les lésions mélanocytaires. Utilisée depuis une dizaine d'années en dermatologie, la MC est arrivée à maturité pour le diagnostic des tumeurs cutanées. Elle se développe pour les dermatoses inflammatoires, les infections cutanées, les angiomes, la cosmétologie mais aussi lors d'excision pour préciser les limites d'une lésion ou la zone d'intérêt à biopsier. Cette technique d'imagerie cutanée représente une innovation majeure et a une place logique en pratique dermatologique.

High-definition optical coherence tomography imaging of melanocytic lesions: a pilot study.

High-definition optical coherence tomography (HD-OCT) is a non-invasive in vivo imaging technique with cellular resolution based on the principle of conventional optical coherence tomography. The objective of this study was to evaluate HD-OCT for its ability to identify architectural patterns and cytologic features of melanocytic lesions. All lesions were examined by one observer clinically and using dermoscopy. Cross-sectional HD-OCT images were compared with histopathology. En face HD-OCT images were compared with reflectance confocal microscopy (RCM). Twenty-six melanocytic lesions of 26 patients were imaged. Identification of architectural patterns in cross-sectional mode and cytologic features of pigmented cells in the epidermis, dermo-epidermal junction, papillary dermis, and superficial reticular dermis in the en face mode was possible by HD-OCT. HD-OCT provides morphological imaging with sufficient resolution and penetration depth to discriminate architectural patterns and cytologic features of pigmented cells in epidermis and dermis. The method appears to offer the possibility of additional three-dimensional structural information complementary to that of RCM, albeit at a slightly lower lateral resolution. The diagnostic potential of HD-OCT regarding malignant melanoma is not high enough for ruling out a diagnosis of malignant melanoma.

Tangential excision of pigmented nail matrix lesions responsible for longitudinal melanonychia: evaluation of the technique on a series of 30 patients.

OBJECTIVES: We sought to assess the shave biopsy technique, which is a new surgical procedure for complete removal of longitudinal melanonychia. We evaluated the quality of the specimen submitted for pathological examination, assessed the postoperative outcome, and ascertained its indication between the other types of matrix biopsies. DESIGN: This was a retrospective study performed at the dermatologic departments of the Universities of Liège and Brussels, Belgium, of 30 patients with longitudinal or total melanonychia. RESULTS: Pathological diagnosis was made in all cases; 23 patients were followed up during a period of 6 to 40 months. Seventeen patients had no postoperative nail plate dystrophy (74%) but 16 patients had recurrence of pigmentation (70%). LIMITATIONS: This was a retrospective study. CONCLUSIONS: Shave biopsy is an effective technique for dealing with nail matrix lesions that cause longitudinal melanonychia over 4 mm wide. Recurrence of pigmentation is the main drawback of the procedure.

High-definition optical coherence tomography: adapted algorithmic method for pattern analysis of inflammatory skin diseases: a pilot study.

High-definition optical coherence tomography (HD-OCT) is a non-invasive technique for morphological investigation of tissue with cellular resolution filling the imaging gap between reflectance confocal microscopy and conventional optical coherence tomography. The aim of this study is first to correlate dermatopathologic descriptors of inflammatory skin conditions with epidermal alteration to features observed by HD-OCT. Secondly, to assess the discriminative accuracy of common inflammatory reaction patterns with epidermal alteration using HD-OCT by applying Ackerman's algorithmic method of pattern recognition. The generated HD-OCT images of 160 patients presenting an inflammatory skin disease were analyzed with respect to the following criteria: visualization of individual cells in the epidermis and dermis and morphology of dermo-epidermal junction, papillary dermis and reticular dermis. A set of morphological features corresponding to dermatopathological descriptors are obtained and the discriminative accuracy of HD-OCT of inflammatory reaction patterns could be demonstrated. These patterns are spongiotic dermatitis, psoriasiform dermatitis, interface dermatitis and ballooning dermatitis. Additional studies to test the sensitivity and specificity of the proposed algorithm for pattern analysis are essential. The other categories of Ackerman's pattern recognition need to be evaluated. This study provides a set of morphological features generated by HD-OCT imaging very similar to those described for reflectance confocal microscopy but with the advantages not only to visualize individual cells up to a depth of 570 µm but also in both slice and en face mode. An adapted algorithmic method for pattern analysis of common inflammatory skin diseases could be proposed. This new technique appears to be a promising method for non-invasive diagnosis, evaluation and management of common inflammatory skin diseases.

Imaging actinic keratosis by high-definition optical coherence tomography. Histomorphologic correlation: a pilot study.

With the continued development of non-invasive therapies for actinic keratosis such as PDT and immune therapies, the non-invasive diagnosis and monitoring become increasingly relevant. High-definition optical coherence tomography is a high-resolution imaging tool, with micrometre resolution in both transversal and axial directions, enable to visualize individual cells up to a depth of around 570 µm filling the imaging gap between conventional optical coherence tomography and reflectance confocal microscopy. We sought to determine the feasibility of detecting and grading of actinic keratosis by this technique using criteria defined for reflectance confocal microscopy compared to histology. In this pilot study, skin lesions of 17 patients with a histologically proven actinic keratosis were imaged by high-definition optical coherence tomography just before excision and images analysed qualitatively. The surrounding normal looking skin has been used as control group. In lesional skin, dyskeratotic and atypical keratinocytes could be noticed with this new technique. An atypical honeycomb pattern in variable degree or a disarranged epidermal pattern could be observed. A good correlation between the dimension of atypia and/or disarrangement of the spinous-granular layer on en face images and the histopathological grading could be demonstrated. Relevant cross-sectional imaging criteria could be defined for the different histopathological variants of actinic keratoses. The surrounding skin displayed features of photodamage. Using features already suggested by reflectance confocal microscopy, the study implies that high-definition optical coherence tomography facilitates in vivo diagnosis of actinic keratosis and allows the grading of different actinic keratosis lesions for increased clinical utility.

Diffuse Muscular Pain, Skin Tightening, and Nodular Regenerative Hyperplasia Revealing Paraneoplastic Amyopathic Dermatomyositis due to Testicular Cancer.

Paraneoplastic dermatomyositis (DM) associated with testicular cancer is extremely rare. We report the case of a patient with skin tightening, polymyalgia, hypereosinophilia, and nodular regenerative hyperplasia revealing seminoma and associated paraneoplastic DM.

Phenotypic characteristics of human type II alveolar epithelial cells suitable for antigen presentation to T lymphocytes.

BACKGROUND: Type II alveolar epithelial cells (AECII) are well known for their role in the innate immune system. More recently, it was proposed that they could play a role in the antigen presentation to T lymphocytes but contradictory results have been published both concerning their surface expressed molecules and the T lymphocyte responses in mixed lymphocyte cultures. The use of either AECII cell line or fresh cells could explain the observed discrepancies. Thus, this study aimed at defining the most relevant model of accessory antigen presenting cells by carefully comparing the two models for their expression of surface molecules necessary for efficient antigen presentation. METHODS: We have compared by flow cytometry the surface expression of the major markers involved in the immunological synapse on the A549 cell line, the most popular model of type II alveolar epithelial cells, and freshly isolated cells. HLA-DR, CD80, CD86, ICOS-L, CD54, CD58 surface expression were studied in resting conditions as well as after IFN-γ/TNF-α treatment, two inflammatory cytokines, known to modulate some of these markers. RESULTS: The major difference found between the two cells types was the very low surface expression of HLA-DR on the A549 cell line compared to its constitutive expression on freshly isolated AECII. The surface expression of co-stimulatory molecules from the B7 family was very low for the CD86 (B7-2) and ICOS-L (B7-H2) and absent for CD80 (B7-1) on both freshly isolated cells and A549 cell line. Neither IFN-γ nor TNF-α could increase the expression of these classical co-stimulatory molecules. However CD54 (ICAM-1) and CD58 (LFA-3) adhesion molecules, known to be implicated in B7 independent co-stimulatory signals, were well expressed on the two cell types. CONCLUSIONS: Constitutive expression of MHC class I and II molecules as well as alternative co-stimulatory molecules by freshly isolated AECII render these cells a good model to study antigen presentation.