Prevalence of atopic dermatitis in Japanese elementary schoolchildren

BACKGROUND: Although there have been several reports on the prevalence of atopic dermatitis (AD) in Japanese schoolchildren based on questionnaires, there has been no nation-wide study of the frequency of this condition diagnosed by dermatologists in regular health check-ups of schoolchildren. OBJECTIVES: The objective of this work was to evaluate precisely the prevalence of AD in elementary schoolchildren in Japan based on regular health check-ups by dermatologists. METHODS: In 2001/2, elementary schoolchildren: first graders (age 6-7 years) and sixth graders (age 11-12 years) were examined by dermatologists in eight prefectures of Japan (Hokkaido, Iwate, Tokyo, Gifu, Osaka, Hiroshima, Kochi and Fukuoka). In each prefecture, public elementary schools were randomly selected from urban and rural districts. We planned to examine about 700 schoolchildren in each of urban first, urban sixth, rural first and rural sixth grades from the eight areas, a total of 22 400 children (700 x 4 x 8). AD was diagnosed by the dermatologists based on the Japanese Dermatological Association criteria for the disease. RESULTS: The point prevalence of AD was 11.2% overall (2664 of 23 719) ranging from 7.4% (Iwate) to 15.0% (Fukuoka) in the eight areas. Seventy-four per cent, 24%, 1.6% and 0.3% of those afflicted were in the mild, moderate, severe and very severe groups, respectively. Overall, the prevalence of first graders was slightly higher than that of sixth graders (11.8% vs. 10.5%, P < 0.01). There was no apparent difference in prevalence between urban and rural districts, or between boys and girls. CONCLUSIONS: The prevalence of AD in Japanese elementary schoolchildren was about 10%, three-quarters of those being mildly affected. This is the first nation-wide study made of Japanese elementary schoolchildren examined by dermatologists to evaluate the frequency of AD.     

南京市2249名中小学生异位性皮炎调查分析

目的：了解南京地区青少年异位皮炎的发病情况。方法：对南京地区４所学校２２４９名７～１８岁年龄段的学生进行普查。结果：１９９８年５～６月南京地区青少年异位性皮炎时的时点患病率为０．８９％,其中城市患病率１．２５％,农村患病率为０．４８％,城市和农村男性患病率分别为１．６８％和０．８０％,女性为０．８２％和０．１８％。同时证实了Ｗｉｌｌｉａｍｓ标准在我国普遍人群应用有较好的诊断效率。结论：（１）１９９８年５～６月南京地区青少年异位性皮炎的时点患病率表现为城市高于农村,男性高于女性;（２）Ｗｉｌｌｉａｍｓ标准适用于我国７～１８岁年龄段人群的流行病学调查。     

Prevalence of atopic dermatitis in Japanese adults

BACKGROUND: Adult atopic dermatitis (AD) in Japan has become a significant social problem, with as many as one-third of adult patients with severe AD absenting themselves from work or classes due to aggravation of the disease. Reports of such patients have become increasingly common in recent years. Despite the pressing need for epidemiological studies to clarify the prevalence and distribution of AD and to determine its aetiology, no previous research has been carried out on the prevalence of AD within the adult population in Japan. OBJECTIVES: To clarify the prevalence of adult AD in Japan, using the U.K. Working Party's diagnostic criteria. METHODS: The subjects of this study were mostly government officials or their family members visiting the Medical Center of Health Science, Toranomon Hospital in Tokyo for annual health check-ups in the period from September 1997 to August 1998. Questionnaires completed by 10 762 persons (8076 men and 2686 women) aged 30 years or above were analysed. The questionnaire consisted of 14 questions on allergic disease. The U.K. Working Party's diagnostic criteria were used after translation into Japanese. Three types of prevalence were used as indicators of prevalence: point, 1-year and lifetime prevalence. RESULTS: The point prevalence, 1-year prevalence and lifetime prevalence of AD in Japanese adults were 2.9%, 3.0% and 3.3%, respectively. No significant statistical differences were observed between the sexes or among age groups within each sex. The survey indicated that 88.6% of those who had ever had AD were currently affected by active AD, while 93.4% of those who had had at least one episode of AD in the past had experienced an episode over the previous year. CONCLUSIONS: This study gives the first indication of the prevalence of adult AD among the Japanese, based on the U.K. criteria. Both the internal and external validity of this study are believed to be high; it would be safe to conclude that the 1-year prevalence of AD in Japanese adult populations living in urban areas is 3.0%.     

Trends in the prevalence of atopic dermatitis in school children: longitudinal study in Osaka Prefecture, Japan, from 1985 to 1997

BACKGROUND: The authors have carried out questionnaire surveys of health symptoms in school children (aged 7-12 years) in Osaka Prefecture, Japan. In this study, the geographical distribution of and trends in the prevalence of atopic dermatitis were evaluated. OBJECTIVES: To assess the relationship between the prevalence of atopic dermatitis in children and the environmental factors, and to estimate future changes of the prevalence of atopic dermatitis. METHODS: A total of seven population surveys were carried out at 2-year intervals between 1985 and 1997 in a total of about 4 million primary school children (460 000-740 000 per survey). RESULTS: The lifetime prevalence of atopic dermatitis increased from 15.0% in 1985 to 24.1% in 1993 but levelled off thereafter. According to the school year, the prevalence was higher in lower-year pupils. However, the prevalence stopped rising earlier in lower-year pupils and began to decrease in 1997 in first- to third-year pupils. The prevalence according to areas was significantly correlated negatively with air pollution and positively with the income index. According to the income classes, the prevalence increased until 1993 but levelled off thereafter in all classes, which reduced the differences among the classes. CONCLUSIONS: The increase of the prevalence of atopic dermatitis in school children stopped in 1993 in Osaka Prefecture, Japan. It is conceivable that the prevalence had reached the saturation level.     

Occupational dermatitis in bakers: a clue for atopic contact dermatitis

6 patients are described who developed contact dermatitis after cereal contact on atopic skin for periods of 2 to 20 years. 2 patients were wheat flour patch-test-positive. They had punch biopsies taken for standard histological and immunohistochemical investigation by labeling with monoclonal antibodies, anti-DR and anti-IgE. Sections showed features of contact dermatitis. There were many dendritic cells located perivascularly in the papilla and in the epidermidis, intensely positive for monoclonal anti-IgE antibody. In control atopic subjects, there were a few perivascular IgE positive cells, probably mastocytes. This study shows that there may be a relationship between some allergens and atopic eczema in patients exposed to them in the course of their work. In some cases, there was a true allergic contact dermatitis, seen through the clinical and histological characteristics, and the results of immunohistochemical study.     

The cost of atopic dermatitis in the Netherlands: an international comparison

BACKGROUND: Only a few international studies have assessed the economic burden of atopic dermatitis (AD), and no costs-of-illness study for AD has been done for the Netherlands. OBJECTIVES: To estimate the incidence, prevalence and health-care costs of AD in the Netherlands and to put these in an international perspective. METHODS: We conducted a retrospective cohort study by using the data of an information system of general practitioners (GPs). To calculate the health-care costs at the primary care level we assessed medical resources utilization. We assessed the costs of patients with more severe AD from a retrospective study of patient files at the department of dermatology of a general hospital. We compared our results with costs-of-illness studies for other countries. RESULTS: The overall general population incidence and prevalence of AD were 0.8% and 2.3%, respectively. The incidence and prevalence were high among children until the age of 6 years, respectively, 3.1% and 11.3%, but decreased rapidly thereafter. The total mean health-care costs per patient were USD71. The most significant costs were due to visits to the GP (USD32) and medication, mostly corticosteroids (USD21). Young children were treated more often with emollients alone. Only 7.8% of patients were referred to a specialist. The mean costs for these patients were USD186. Costs-of-illness studies for Australia, Germany, the U.K., the U.S.A. and the Netherlands suggested that the costs associated with AD vary considerably across countries. Estimates of the costs-of-illness for AD ranged from USD71 in the Netherlands to USD2559 in Germany per patient due to variation in the study population (GP vs. hospital) and the number of cost components included. Studies that included costs due to the time spent on treatment had relatively high estimates. CONCLUSIONS: The prevalence and incidence of AD are high among young children. In general, the health-care costs for AD were low. Patients' out-of-pocket costs were relatively high.     

Polymorphisms within the C3 gene are associated with specific IgE levels to common allergens and super-antigens among atopic dermatitis patients

Abstract:  Atopic dermatitis (AD) is a chronic inflammatory skin disease. Twin and family studies suggest a strong genetic component of the disease. The keratinocytes secrete high amounts of C3 after stimulation with pro-inflammatory cytokines, which may play a functional role in skin inflammation. In this study, we genotyped four different single nucleotide polymorphisms (SNPs) by melting curve analysis using sequence specific hybridization probes in a well-characterized cohort of AD patients. Among four SNPs within C3 gene, higher frequencies of rs10410674 (23.5% vs 12.2%) and rs366510 (13.8% vs 6.5%) were observed in AD patients as compared with control group. None of the tested polymorphisms showed significant association with the risk of the disease phenotype. Analysis of rs10402876 SNP revealed its association with less severe AD disease expression (low SCORAD). Total serum IgE levels were not different among AD patients having any of the four SNPs. However, we observed significantly less serum-specific IgE levels to common allergens ( Dermatophagoides pteronyssinus and birch pollens) and Staphylococcal enterotoxin B in AD patients having rs366510 SNP. Thus, associations of polymorphism within C3 gene with less severe AD disease expression and a weaker sensitization to common allergens suggest the role of these SNPs in the development of AD.     

No association between serum eosinophil cationic protein and atopic dermatitis or allergic rhinitis in an unselected population of children

Background In order to obtain background references when dealing with serum eosinophil cationic protein (s‐ECP) measurements in children with allergic diseases, population‐based studies are important. The objectives of our study were to explore the strength of associations between the s‐ECP level and atopic dermatitis (AD), allergic rhinitis (AR) and asthma in an unselected northern Norwegian schoolchildren population. Methods s‐ECP was sampled from 396 schoolchildren aged 7–12 years from Sør‐Varanger community, northern Norway as a part of a population‐based study of allergy. In advance, anamnestic information concerning a history of AD, AR and asthma were obtained. The children underwent a clinical investigation, including skin prick tests and peak expiratory flow measurements, where the presence of AD, AR and asthma were evaluated. The associations of these diseases to the s‐ECP values were examined in bivariate statistical analysis. Results No statistical significant associations were detected in bivariate analysis between s‐ECP and AD, AR or asthma: the mean s‐ECP in children without self‐reported AD/AR/asthma was 4.6 µg/L [95% confidence interval (CI) 4.0–5.2]. The mean s‐ECP in children with self‐reported AD or AR or asthma was 5.2 µg/L (95% CI 4.1–6.2), 4.6 µg/L (95% CI 3.5–5.7) and 6.4 µg/L (95% CI 4.4–8.3), respectively. The highest mean s‐ECP level was measured in children with clinically diagnosed asthma; 7.1 µg/L (95% CI 4.0–10.3). Above the 75‐percentile level of s‐ECP, only 17.2% of the children had a history of asthma. Conclusions In this unselected children population, the occurrence of AD or AR was not reflected by an increase in the s‐ECP level. The s‐ECP was increased in children with asthma, but was not statistically significant. Furthermore, the majority of children with high s‐ECP values were not asthmatics. We conclude that the associations between s‐ECP and allergic diseases are weak in an unselected population of children.     

Tacrolimus decreases the expression of eotaxin, CCR3, RANTES and interleukin-5 in atopic dermatitis

Background There is a lack of studies on the effect of tacrolimus on eosinophils and related molecules including eotaxin, CCR3, RANTES and interleukin (IL)‐5. Objectives To investigate the effects of tacrolimus on in vivo eosinophil counts and on the related molecules eotaxin, CCR3, RANTES and IL‐5 in patients with atopic dermatitis (AD). Methods Lesional skin specimens and sera were obtained from 15 patients with AD and from 15 normal controls. For 8 weeks, the patients with AD applied 0·03% tacrolimus ointment to all affected areas twice daily. Blood sampling and skin biopsies were then repeated. We evaluated serum eotaxin and IL‐5 levels, and tissue eotaxin, CCR3, RANTES and IL‐5 levels. Additionally, tissue levels of eotaxin and CCR3 mRNA were measured. Results After treatment with topical tacrolimus twice daily for 8 weeks, significant decreases were found in serum IL‐5 levels, immunoreactive cell counts of eotaxin, IL‐5, CCR3 and RANTES in AD skin, and tissue eosinophil counts. However, the change in the serum eosinophil count was not statistically significant, and mRNA levels of eotaxin and CCR3 were not decreased significantly after treatment. Conclusions Topical tacrolimus reduces the number of eosinophils in tissue and suppresses the expression of eotaxin, CCR3, RANTES and IL‐5 related to proliferation, recruitment, activation and survival of eosinophils.     

特应性皮炎中相关细胞因子的研究进展

特应性皮炎(AD)发病机制复杂,其中免疫学功能的紊乱和调节失衡是AD发病的中心环节。本文对近年来报道的与AD发病相关的细胞因子进行综述。     

Effectiveness of dupilumab in pediatric patients with a nummular phenotype of atopic dermatitis

The nummular phenotype of atopic dermatitis is clinically characterized by pruritic, coin-shaped plaques that are frequently recalcitrant to treatment. In this study, a retrospective chart review was conducted to evaluate the effectiveness and safety of dupilumab in children with nummular lesions of dermatitis. Twelve out of 14 patients demonstrated significant clinical improvement at a median time of 2.5 months (interquartile range, 1–4) after dupilumab initiation. A single case of paradoxical psoriasiform eruption was the only side effect reported in our cohort.     

保湿剂并用糖皮质激素治疗异位性皮炎的疗效观察

目的：研究保湿剂对外用糖皮质激素治疗异位性皮炎疗效的影响。方法：通过随机对照临床研究，采用湿疹面积及严重度指数评分法，对外用糖皮质激素和保湿剂治疗45例轻中度异位性皮炎患者的临床疗效进行评估。结果：与单独外用糖皮质激素或保湿剂相比，联合外用糖皮质激素加保湿剂治疗轻、中度异位性皮炎，较单用糖皮质激素疗效显著，单独外用保湿剂可明显减轻轻中度异位性皮炎患者的临床症状。结论：外用保湿剂能增强局部糖皮质激素的疗效，单独外用保湿剂治疗异位性皮炎可获得与糖皮质激素相近的疗效。     

Polymorphisms within the CTLA4 gene are associated with infant atopic dermatitis

BACKGROUND: Atopic dermatitis (AD) is one of the most common childhood disorders. It can have a significant impact on the physical and psychological well-being of affected individuals. Although environmental triggers are important, AD also has a strong genetic component. Identifying genes associated with AD may help to understand better the basis of this disorder and its relationship with other allergic disorders such as asthma. OBJECTIVES: Polymorphisms in the gene encoding the inhibitory CTLA4 receptor, an important regulator of T cells, are associated with asthma as well as autoimmune disorders. We have now tested whether polymorphisms in the CTLA4 gene are also associated with early childhood AD. METHODS: A family-based cohort of 112 children and their parents was recruited from Western Sydney, Australia. All children were seen by a paediatric dermatologist and presented with AD within the first 3 years of life. Using the transmission disequilibrium test, individual and haplotypic associations with the +49 and CT60 polymorphisms in exon 1 and the 3' nontranslated DNA of the CTLA4 gene were tested. RESULTS: Single tests of association revealed significant association of the +49(A) [P = 0.037, odds ratio (OR) 1.59, 95% confidence interval (CI) 1-2.55] and borderline significance of the CT60(A) alleles (P = 0.055, OR 1.51, 95% CI 1-2.38). Significant association of the +49(A)/CT60(A) haplotype was detected (P = 0.002, OR 1.78, 95% CI 1.2-2.65). CONCLUSIONS: Polymorphisms within the gene encoding CTLA4 were associated with early onset infant AD. This is in agreement with findings from asthmatic cohorts, suggesting that the +49(A)/CT60(A) haplotype is a genetic risk factor common to asthma and AD.     

Clinical effectiveness of a silk fabric in the treatment of atopic dermatitis

BACKGROUND: In children with atopic dermatitis (AD), eczema is easily aggravated by contact with irritant factors (e.g. aggressive detergents, synthetic and woollen clothes, climatic factors). OBJECTIVES: To evaluate the effectiveness of a special silk fabric (MICROAIR DermaSilk) in the treatment of young children affected by AD with acute lesions at the time of examination. METHODS: Forty-six children (mean age 2 years) affected by AD in an acute phase were recruited: 31 received special silk clothes (group A) which they were instructed to wear for a week; the other 15 served as a control group (group B) and wore cotton clothing. Topical moisturizing creams or emulsions were the only topical treatment prescribed in both groups. The overall severity of the disease was evaluated using the SCORAD index. In addition, the local score of an area covered by the silk clothes was compared with the local score of an uncovered area in the same child. All patients were evaluated at baseline and 7 days after the initial examination. RESULTS: At the end of the study a significant decrease in AD severity was observed in the children of group A (mean SCORAD decrease from 43 to 30; P = 0.003). At the same time, the improvement in the mean local score of the covered area (from 32 to 18.6; P = 0.001) was significantly greater than that of the uncovered area (from 31 to 26; P = 0.112). CONCLUSIONS: The use of special silk clothes may be useful in the management of AD in children.