The epidermal barrier in atopic dermatitis

Epidermal barrier function is abnormal in individuals with atopic dermatitis (AD). It is controversial whether primary epidermal barrier abnormalities alone account for the physiological and clinical abnormalities found in those persons with AD or whether the observed barrier dysfunction is a consequence of primary immunologic abnormalities. Recent evidence is strengthening the argument for the former hypothesis. Attention to epidermal barrier care (ie, gentle skin care) has long been an important part of the therapy of AD. Advances in our understanding of the biology of the epidermal barrier and how this relates to the clinical manifestations of this disease has important consequences for new therapeutic approaches in the management of AD.     

The role of infection in atopic dermatitis

explain this tendency to develop infections. A decrease in the number and function of CD8+ suppressor/cytotoxic T cells from peripheral blood of AD patients has been reported.2 This could explain the increased incidence of cutaneous viral and fungal infections observed in these patients. Monocytes from AD patients secrete increased levels of interleukin (IL)-10 that can inhibit T cell mediated responses.3 Leukocytes from patients with AD have been found to produce decreased amounts of interferon gamma (IFN-g),4 which is required for the     

The cutaneous pathology of atopic dermatitis

Sixteen skin biopsy specimens from early eruptive, evolving papules and well-developed plaques were obtained from eight patients with established atopic dermatitis. We found that the chronological and histopathological sequence begins with a perivascular interstitial spongiotic dermatitis, evolves into a psoriasiform microvesicular spongiotic dermatitis, which is sometimes focally lichenoid, and eventually concludes as a psoriasiform dermatitis. Thus, atopic dermatitis has characteristic and diagnostic histopathologic findings. These are portrayed and contrasted to what has been previously reported.     

Lysozyme in atopic dermatitis

The aim of the present study was to determine the levels of lysozyme in serum and saliva in 10 patients with atopic dermatitis (AD). A significantly decreased lysozyme levels in saliva compared to controls (p less than 0.01) were showed, whereas no differences were found in lysozyme activity in serum of patients and controls. The reduced levels in saliva can hardly be explained. The decreased levels of lysozyme in external fluids may be one explanation for the well-known predisposition for AD patients to an increased susceptibility to many cutaneous infections.     

Pyridoxine in atopic dermatitis

Summary A previous study has reported benefit when pyridoxine hydrochloride was given to patients with atopic dermatitis. To investigate this in children, we performed a randomized, double-blind, parallel-group, placebo-controlled trial. Forty-eight children with moderate or severe atopic dermatitis were recruited and, of those who completed the study, 19 received pyridoxine hydrochloride 50 mg once daily for 4 weeks and 22 received placebo. Disease activity was monitored by clinical severity scores measuring the extent and degrees of erythema recorded by the investigator and symptom scores (daytime itch and nocturnal sleep disturbance) recorded by parents. There was no statistically significant difference between the two groups at the end of treatment. We have been unable to demonstrate clinical benefit from pyridoxine supplementation in children with atopic dermatitis.     

Urticaria in atopic dermatitis

During examinations of 479 patients referred for atopic dermatitis and 520 with urticaria it was found that in the first group coexistence of these diseases was frequently occurring, and in the second group it was rare. Food allergens caused slightly more frequently episodes of urticaria than exacerbations of atopic dermatitis. Coexistence of urticaria with atopic dermatitis was particularly frequent in patients: a) with a high IgE titre, b) with a history of allergy in the families of both parents, c) in patients with respiratory allergy associated with skin lesions.     

Biologics in atopic dermatitis

Atopic dermatitis (AD) accounts for a significant share of chronic inflammatory skin disorders. There is a niche for the development of biologics to treat recalcitrant autoinflammatory stage AD seen mostly in adults. The heterogeneity of patient response to various existing biotherapies points to involvement of various immune responses and suggests that therapies must preferably target early development of allergen‐specific B‐ and T‐cell clones. In addition to immune targets, tissue factors that help restore the normal epidermal environment constitute interesting therapeutic tools. Several approaches are needed to find the appropriate targets in a field where so many have been investigated without definitive proof of concept for human systemic therapy. The keys to success are probably (1) to influence the inflammatory skin pattern towards less pruritogenic effects, requiring us to better understand pruritogenic inflammation and (2) to limit the amplification loop of disease by attacking abnormal regulatory mechanisms which perpetuate skin autoinflammation.     

特应性皮炎的转录组学研究进展

【摘要】 随着基因芯片技术、RNA测序技术等转录组学技术发展,特应性皮炎（AD）发病中重要的相关影响因素逐渐被揭示,如不同T辅助（Th）细胞的亚型以及其他免疫相关细胞如巨噬细胞、朗格汉斯细胞;在AD的瘙痒及皮肤屏障破坏方面,相关免疫细胞如Th2细胞及角质形成细胞等所释放白细胞介素4、白细胞介素13、聚丝蛋白、兜甲蛋白等活性物质的异常变化起着主要作用。同时,转录组技术已被用于分析患者治疗前后转录谱的变化从而对患者的病情和治疗效果进行评估等。本文总结近年来在AD转录组学方面的研究进展。     

Cromones in atopic dermatitis

Summary Three new cromones have been studied that are supposed to be better absorbed and to have a wider spectrum of anti-allergic activity than disodium cromoglycate. Pretreatment with i.d. injection of 10 g FPL 52758 significantly reduced the weal and flare reaction induced by specific antigen in 11 patients with atopic dermatitis. The weal and flare reaction was not reduced in the same patients when 1.5 mg of FPL 52758 was applied topically under occulusion for a 24-h period prior to challenge with antigen. The itch and slight pain caused by antigen injection was not experienced in the FPL 52758 pretreated areas.Preliminary clinical results were obtained with the cromone FPL 52757, but due to possible hepatotoxicity this trial was not completed. Another similar cromone without hepatotoxicity was used in a double blind within-patient study. Nine patients with mild to moderate atopic dermatitis were treated with FPL 57787 (5%) ointment and matching placebo ointment. No significant improvement was observed after 4 weeks of treatment with the cromone containing ointment.     

The immune system and atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease with a complex pathogenesis. It is clinically well-defined and represents one manifestation of the atopic state, along with asthma, food allergy and/or allergic rhinitis. Within the last several decades, there has been much evidence to support the contribution of immune mechanisms in the pathogenesis of AD. It has also been documented that the prevalence of all atopic disease, including AD, has been increasing, although the environmental factors that may be contributing to this increase are not clearly defined. A better understanding of the underlying immunopathogenesis of AD should aid in better clinical management and development of new treatment options.     

The role of Dermatophagoides pteronyssinus in atopic dermatitis

The role of Dermatophagoides (D.) pteronyssinus in atopic dermatitis (AD) was investigated by use of skin prick test (SPT) and total and specific IgE (RAST) to D. pteronyssinus. The study included 43 patients (17 male and 26 female), mean age 42.3 (range 19-77) years. All study patients met the Hanifin and Rajka criteria. Patients were divided into two groups: "pure" AD (n=27; 12 male and 15 female), mean age 46.3 (range 19-77) years; and AD with respiratory symptoms (AD+RS, n=16; 5 male and 11 female), mean age 38.4 (range 17-75) years. Control group consisted of 15 healthy subjects (7 male and 8 female; mean age 49.0, range 24-64 years), with no personal or family history and signs of atopy. Both patient groups had a higher total serum IgE than control subjects (p<0.05). In the "pure" AD group, SPT was positive in 5/27 (18.5%) and RAST to D. pteronyssinus in 4/27 patients. In the AD+RS group, SPT was positive in 10/16 (62.5%) and RAST to D. pteronyssinus in 8/16 (50%) patients. Concordance between SPT and RAST was observed in both groups; 80% of SPT positive patients were RAST positive. D. pteronyssinus was found to play an important role as a trigger factor in AD patients.     

The prevalence of atopic dermatitis in Oregon schoolchildren

BACKGROUND: Although surveys from many parts of the world have shown that the prevalence of atopic dermatitis (AD) in schoolchildren has increased greatly in the past 40 years, there is no current prevalence information from the United States. OBJECTIVE: Our objective was to investigate the utility of a recently developed European questionnaire to estimate the prevalence of AD in urban and rural Oregon schoolchildren. METHODS: The self-administered Schultz-Larsen questionnaire (SLQ) of AD symptoms and history was completed by the parents of a broad socioeconomic and ethnic mix of 5- to 9-year-old schoolchildren from 6 urban and 2 rural elementary schools in Oregon. Validation assessments included comparisons of the questionnaire scores with clinical examination in a group of age-matched children and with specific history components known to correlate with AD. RESULTS: Data showed a prevalence of 17.2% using standard scoring criteria for the SLQ and with a lower limit of 6.8% according to highly stringent criteria derived from the validation study using dermatologic examination. A single question ("Has a doctor ever said that your child has eczema?") was highly concordant with the questionnaire determination, yielding very high predictive accuracy (91.2%). CONCLUSION: This study of childhood AD frequency indicates a high prevalence of AD in the United States, comparable to that recently observed from studies in Europe and Japan. (J Am Acad Dermatol 2000;43:649-55.).