Aeroallergens and food allergens are able to elicit eczematous skin reactions after epicutaneous application. As no gold standard for aeroallergen provocation in AE exists, the relevance of aeroallergens for AE flares may be evaluated by APT in addition to SPT and sIgE. The data may contribute to the international standardization of the APT.

Standardized skin surface biopsy (SSSB) is an appropriate method for measuring the density of Demodex folliculorum (Dd). Nevertheless, the observation of a clinical case demonstrates that, contrary to what was presumed before, a single SSSB can fail to collect the complete biotope of the mite. This could give rise to false negative results regarding the measurement of Dd.

Juvenile xanthogranuloma(JXG) is the variant of non-Langerhans' cell histiocytosis. The orange-yellow background coloration with clouds of paler yellow deposits is the most characteristic dermoscopic finding of JXG. Other dermoscopic features include erythematous border, subtle pigment network and white linear streak. The objective of this study was to present the structural correlation between dermoscopic features and histopathological findings of JXG and to find the different dermoscopic features in various stages of JXG. Eleven patients with histologically proven JXG were examined with polarized light dermoscopy. Histopathological findings were assessed and dermoscopic features including setting sun appearance, clouds of paler yellow globules, whitish streak, and branched and linear vessels were evaluated. Among 11 patients, five patients were in early evolutionary stage, four patients in fully developed stage and two in late regressive stage. The setting sun appearance was found in all patients in different stages except one in late regressive stage (90.9%). The clouds of paler yellow globules were present in nine patients (81.8%) and were constant features in fully developed stage and late regressive stage. The whitish streak was present in four patients (36.4%) and telangiectasia in 10 patients (81.8%). The setting sun appearance may hold diagnostic value in early evolutionary stage to fully developed stage, but not in late regressive stage. The clouds of paler yellow globules are more predominant in fully developed stage and late regressive stage. In addition to the use of dermoscopy as an accurate diagnostic tool for differential diagnosis, it could be applied in evaluation of histopathological maturation of JXG.

Hereditary progressive mucinous histiocytosis is a rare autosomal dominant non-Langerhans cell histiocytosis. We describe a sporadic case of this syndrome in a 64-year-old woman who had multiple dark-red dome-shaped papulonodules located mainly on the back of her hands, forearms and thighs. Light microscopy revealed a circumscribed upper dermal aggregate of ovoid or spindle-shaped histiocytes with abundant mucin deposition. Iron deposits and numerous mast cells were scattered throughout the tumour but giant cells were rare. Electron microscopy revealed a high number of zebra bodies and myeloid bodies in the cytoplasm of the histiocytes. Immunohistochemistry showed positive labelling with alpha-1 antitrypsin, Factor XIIIa and CD68, while CD1a, CD34 and S100 protein were negative. The differential diagnosis of histiocytic syndromes is discussed.