Aspect en microscopie confocale par réflectance in vivo des kératoses actiniques: Reflectance confocal microscopy features of actinic keratoses.

Though the diagnosis of actinic keratoses is most often clinical, it is sometimes necessary to use non-invasive imaging methods to confirm this diagnosis. Reflectance confocal microscopic examination of actinic keratosis may reveal hyperkeratosis (i.e., detached, isolated or scaly corneocytes), parakeratosis (i.e., nucleated cells in the stratum corneum), dilated vessels and signs of solar elastosis, including clusters of moderately reflecting material and/or undulating shiny elastic fibres that are clearly visible in the superficial dermis. Hopefully, new in vivo microscopic imaging techniques such as line-field confocal optical coherence tomography will make it possible to obtain a three-dimensional examination of the skin and, thus, to further improve diagnostic accuracy of these lesions. © 2019 Elsevier Masson SAS. All rights reserved. Cet article fait partie du numéro supplément Kératoses actiniques : comprendre et traiter réalisé avec le soutien institutionnel de Galderma International.

Reflectance confocal microscopy identification of subclinical basal cell carcinomas during and after vismodegib treatment.

BACKGROUND: Recently, it has been shown that reflectance confocal microscopy (RCM) could identify subclinical basal cell carcinoma (BCC) during vismodegib treatment of locally advanced BCC. OBJECTIVES: To evaluate specificity and sensitivity of clinical, dermoscopic and RCM examination for BCC in patients with multiple BCCs treated by vismodegib. METHODS: Ninety four BCCs had 710 clinical, dermoscopic and RCM examinations during 72 weeks of vismodegib treatment. Thirty-eight were biopsied at the end of the treatment. Sensitivity and specificity for these 38 lesions were calculated. BCC diagnoses of clinical, dermoscopic and RCM examination on all the 710 investigations were compared using chi-square test. RESULTS: Reflectance confocal microscopy was extremely more sensitive than dermoscopy and clinical examination and slightly less specific (sensitivity of 95%, 35% and 33% and specificity of 81%, 88% and 86% for RCM, dermoscopy and clinical examination, respectively) for the identification of residual BCC in the 38 biopsied cases. Considering all the 710 observations, RCM correctly diagnosed more BCCs than dermoscopy and clinical examination. CONCLUSION: Reflectance confocal microscopy is a non-invasive technique that can detect subclinical residual BCC during and after vismodegib treatment helping the clinician to identify incomplete tumour regression.

Reflectance confocal microscopy for the diagnosis of vulvar naevi: six cases.

BACKGROUND AND OBJECTIVES: The differential diagnosis between vulvar naevi and melanoma is challenging. In vivo reflectance-mode confocal microscopy (RCM) is an emerging technique that allows non-invasive high-resolution imaging of the skin and mucosa. It has recently been used for the study of vulvar melanosis and melanoma, but it has not been so far employed for the diagnosis of genital naevi. The objective of this study is to evaluate RCM features of vulvar naevi and to compare them with dermoscopical and histopathological aspects. METHODS: Clinical, dermoscopical, in vivo RCM and histological features of six vulvar naevi were evaluated. RESULTS: The clinical and/or dermoscopical aspects were suspicious in all six cases. RCM showed a blue naevus, an atypical genital naevus, a junctional naevus and three compound naevi that were later confirmed by histological examination. In one compound naevus, RCM showed focal cytological atypia and architectural irregularity without clear features of malignancy, confirmed by histological examination. CONCLUSIONS: Reflectance-mode confocal microscopy can play a role in non-invasive diagnosis of vulvar naevi, but further broader studies are required to validate our observations.

In vivo confocal microscopic substrate of grey colour in melanosis.

BACKGROUND: Melanosis is the most common cause of mucosal pigmentation and can be clinically difficult to differentiate from early melanoma (MM). Dermoscopy can help in the distinction between melanosis and MM, but in some instances, melanoses may exhibit overlapping features with MM such as the presence of grey colour. OBJECTIVE: We sought to evaluate whether reflectance confocal microscopy (RCM) can help to better understand the dermoscopic features of melanoses in order to assist clinicians in their diagnosis. METHODS: All melanoses diagnosed between June 2011 and December 2014 in the Departments of Dermatology of the University of Saint-Etienne (France) and of Modena and Reggio Emilia (Italy), for which dermoscopic and RCM images were available, were included. Twenty-two lesions were biopsied to confirm the clinical diagnosis, whereas the others did not present any change at a follow-up of at least 6 months. The correlation between dermoscopic and RCM features were evaluated by the Spearman's rho correlation coefficient. RESULTS: 55 melanoses were studied: 31 of the oral mucosa and 24 of the genital mucosa. 49% (n = 27) of melanoses exhibited a grey colour under dermoscopy. The grey colour correlated with the presence of melanophages under RCM (ρ = 0.424, P = 0.002). CONCLUSION: Our findings highlight that the presence of the grey colour on dermoscopy, considered as an alerting feature, is common in melanoses and it is related to the presence of melanin-laden inflammatory cells in the papillary dermis on RCM. When it is present as a 'pure' feature not associated to other colours than brown or to atypical dermoscopical structures, it could be related to the diagnosis of melanosis.

Inefficacy of alcohol-based hand rub on mites in a patient with hyperkeratotic scabies.

BACKGROUND: The World Health Organization is strongly promoting alcohol-based hand rubs to interrupt transmission of pathogens within the healthcare environment, and in some hospitals they are being recommended in cases of scabies. However, there are no studies that demonstrate the efficacy of such hand rubs against scabies. AIM: To evaluate the viability of Sarcoptes scabiei after the application of various topical antiseptics used for hand hygiene, and the effect of hand washing on the number of parasites present on the skin surface of a patient with scabies. METHODS: We applied three different topical antiseptics (two alcohol-based and one povidone-iodine-based) to the skin of one hand that was affected by scabies, and took a skin scraping of each area to evaluate the viability of the mites over time. A skin scraping of a control area without antiseptic application was also taken. We also tested the antiseptics directly on the mites. Statistical comparison between the percentages of vital mites in the different samples was assessed using the χ(2) test. We also captured a dermoscopic image of the other hand before and after hand washing to count the number of parasites on the skin surface. RESULTS: Topical antiseptics did not reduce the number of living mites compared with control skin, and hand washing did not reduce the number of parasites on the skin surface. CONCLUSIONS: Application of topical antiseptics does not reduce the viability of S. scabiei, and is therefore unable to prevent the transmission of scabies. The usefulness of hand washing in preventing transmission of scabies to new subjects remains to be investigated.