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An important feature of atopic eczema (AE) is a decreased skin barrier function. The stratum corneum (SC) lipids - comprised of ceramides (CERs), free fatty acids (FFAs) and cholesterol - fulfil a predominant role in the skin barrier function. In this clinical study, the carbon chain length distribution of SC lipids (FFAs and CERs) and their importance for the lipid organization and skin barrier function were examined in AE patients and compared with control subjects. A reduction in FFA chain length and an increase in unsaturated FFAs are observed in non-lesional and lesional SC of AE patients. The reduction in FFA chain length associates with a reduced CER chain length, suggesting a common synthetic pathway. The lipid chain length reduction correlates with a less dense lipid organization and a decreased skin barrier function. All changes are more pronounced in lesional SC compared with non-lesional skin. No association was observed between lipid properties and filaggrin mutations, an important predisposing factor for developing AE. The results of this study demonstrate an altered SC lipid composition and signify the importance of these changes (specifically regarding the CER and FFA chain lengths) for the impaired skin barrier function in AE. This provides insights into epidermal lipid metabolism as well as new opportunities for skin barrier repair.

The purpose of the study was to evaluate a self-administered questionnaire on hand dermatitis that was developed to identify persons with hand dermatitis in epidemiological studies. A total of 109 nurses were subject to dermatological examination of the hands within 1 month of returning the questionnaire. 2 types of questionnaire diagnoses were made: a 'symptom-based' diagnosis and a 'self-reported diagnosis'. These were compared to the medical diagnosis of hand dermatitis. The prevalence of hand dermatitis in the 12 months before the study, based on the medical diagnosis, was 18.3%. The prevalence according to the symptom-based diagnosis and the self-reported diagnosis was 47.7% and 17.4%, respectively. The sensitivity and specificity of the symptom-based diagnosis were 100% and 64%, respectively. It is concluded that the symptom-based diagnosis can be used as screening instrument for the detection of cases in large study populations, if followed by dermatological examination of persons with a positive diagnosis. The sensitivity and specificity of the self-reported diagnosis were 65% and 93%, respectively. It is concluded that the self-reported diagnosis can be used to obtain a rough estimate of the prevalence, although comparison of prevalence figures between study populations may be distorted due to a difference in reporting of hand dermatitis. The results of the study illustrate the size of the differences in prevalence estimates that may arise as a result of differences in the definition and method of diagnosing hand dermatitis.

Most moisturisers showed some beneficial effects, producing better results when used with active treatment, prolonging time to flare, and reducing the number of flares and amount of topical corticosteroids needed to achieve similar reductions in eczema severity. We did not find reliable evidence that one moisturiser is better than another.

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This highly sensitive assay also proved to have high positive and negative predictive values (95.7% and 100%), facilitating the accurate, rapid diagnosis conducive to targeted rather than empirical therapy for dermatophytoses.

Isolation of a Microsporum canis gene family encoding three subtilisin-like proteases expressed in vivo. J Invest Dermatol 119:830-5 Gonzalez A, Sierra R, Cardenas ME et al. (2009) Physiological and molecular characterization of atypical isolates of Malassezia furfur. Quantitative culture of Malassezia species from different body sites of individuals with or without dermatoses. Med Mycol 39:243-51 Naldi L, Rebora A (2009) Clinical practice. Seborrheic dermatitis. N Engl J Med 360:387-96 Oh BH, Lee YW, Choe YB et al. (2010) Epidemiologic study of Malassezia yeasts in seborrheic dermatitis patients by the analysis of 26S rDNA PCR-RFLP. Ann Dermatol 22:149-55 Ran Y, Yoshiike T, Ogawa H (1993) Lipase of Malassezia furfur: some properties and their relationship to cell growth. J Med Vet Mycol 31:77-85 Staib P, Kretschmar M, Nichterlein T et al. (1999) Host-induced, stage-specific virulence gene activation in Candida albicans during infection. Mol Microbiol 32:533-46 Tajima M, Sugita T, Nishikawa A et al. (2008) Molecular analysis of Malassezia microflora in seborrheic dermatitis patients: comparison with other diseases and healthy subjects. J Invest Dermatol 128:345-51 Xu J, Saunders CW, Hu P et al. (2007) Dandruffassociated Malassezia genomes reveal convergent and divergent virulence traits shared with plant and human fungal pathogens. Proc Natl Acad Sci USA

Most patients with autosomal recessive lamellar ichthyosis are known to have markedly impaired skin barrier function. We hypothesize that this may be due to imperfections in the composition and fine structure of the intercellular stratum corneum lipids. The aim of the present study was to test this hypothesis. To characterize the barrier properties in three female patients with lamellar ichthyosis, the following parameters were used and compared with those of healthy volunteers: transepidermal water loss, stratum corneum lipid profiles after topical acetone/ether extraction on the flexure side of the forearm, and small-angle x-ray diffraction. The extracted lipids were separated using high performance thin-layer chromatography and quantified, and the ceramide profile was determined. Small-angle x-ray diffraction was used to obtain information on the molecular structure and organization of the intercellular lipid domains of stratum corneum using stratum corneum scales collected by scraping. Transepidermal water loss was significantly increased in all three patients. Lipid analysis showed significant differences in the relative amounts of ceramide fractions 2-3a-3b-4-5, free fatty acid-ceramide ratio, and free fatty acid-cholesterol ratio. Small-angle x-ray diffraction showed smaller repeated distances of lipid bilayers in stratum corneum samples of the patients compared with the healthy volunteers. An additional diffraction peak was found in the patients compared with the healthy volunteers, which can be ascribed to crystalline cholesterol. These data suggest that there might be a relation between the impaired barrier function and stratum corneum lipid structural and composition changes.