Delayed- and immediate-type reactions in the atopy patch test with food allergens in young children with atopic dermatitis.

In recent years, the atopy patch test (APT) has been suggested as an addition in the allergological work-up of children with atopic dermatitis (AD) and suspected food allergy. We initiated a prospective clinical study in children with AD younger than 3 yr, to evaluate the additional clinical value of the APT next to our own standardized allergological work-up in case of a suspected food allergy. One hundred and thirty-five children were included in the study. They were tested using the skin application food test (SAFT), the APT and measurement of specific IgE. The allergens used in the skin tests were freshly prepared food stuffs and included commercially available cow's milk (CM), the egg white of a hard boiled hen's egg and mashed peanuts in a saline solution. Allergy was defined using a flowchart incorporating the results from the SAFT, oral challenges (OCs) and elimination and (re)introduction periods. To determine the additional value of the APT next to the SAFT, we analyzed the SAFT negative patients per allergen and used an exact binary logistic analysis to evaluate the simultaneous effects of the APT and measurement of specific IgE, calculating mutually adjusted odds ratios (ORs) for positive APTs and specific IgE levels above 0.70 U/l. We found clinically relevant food allergies in 23% (egg white) to 28% (CM and peanut) of our study population. Positive SAFT reactions were observed in 14% (peanut), 16% (egg white) and 21% (CM) of our patient population. Next to the SAFT, we did not observe a significant additional value of the APT for the diagnosis of CM or egg white allergy, but we did find a significant additional value for the diagnosis of peanut allergy (OR = 11.56; p < 0.005, 2-sided). In clinical practice this statistically significant value does not exclude the need for OC and controlled elimination and (re)introduction periods due to the presence of false-negative as well as false-positive results in the APT. In conclusion, we could not find enough support for the current addition of the APT to our standardized allergological work-up in young children below the age of 3 yr with AD and suspected food allergy. At the moment the additional value of the classical delayed-type APT next to the SAFT seems to be very limited at best in this study population and does not justify the time-consuming nature of the skin test.

Elevated levels of plasma matrix metalloproteinase-9 in patients with atopic dermatitis: a pilot study.

Matrix metalloproteinase (MMP)-9 has been shown to play a role in the infiltration of inflammatory cells in various tissues. It is thus part of the pathogenesis of many inflammatory diseases, including asthma and allergic rhinitis/conjunctivitis. We compared plasma MMP-9 levels of 20 patients with atopic dermatitis (AD) with that of 17 control subjects. Additional outcome parameters consisted of the modified objective SCORing Atopic Dermatitis and the Three Item Severity score in patients, and peripheral blood leucocytes and eosinophils in both groups. Plasma MMP-9 levels were found to be significantly higher in patients compared with controls, supporting a role for MMP-9 in the pathogenesis of AD.

Treatment of patients with atopic dermatitis using wet-wrap dressings with diluted steroids and/or emollients. An expert panel's opinion and review of the literature.

BACKGROUND: The use of dampened bandages to reduce inflamed eczema (synonyme dermatitis) is an old remedy. In order to evaluate the current indications for so-called wet-wrap treatment (WWT) for atopic dermatitis (AD), and to compare the different currently recognized methods, a group of experts critically reviewed their own expertise on WWT in respect to the existing literature on the subject. RESULTS: WWT is well tolerated in eczema due to the cooling effect on the skin and the rapid improvement in skin inflammation. It has been shown to be an extremely effective treatment for acute erythrodermic dermatitis, therapy-resistant AD and intolerable pruritus. Advantages of WWT include rapid response to therapy, reduction in itch and sleep disturbance, and potential for reduction in usage of topical corticosteroids (TCS). However, disadvantages include high cost, the necessity for special training in usage, potential for increased TCS absorption, increased cutaneous infections and folliculitis, and poor tolerability. Precautions to reduce the risks of long-term treatment should include education, monitoring of weight and height and, if necessary, serum cortisol levels. In adolescents the risk of striae from TCS absorption around puberty is high, and WWT with TCS in this age group should be used as a short-term therapy only and with extreme caution. To reduce risks, dilutions of steroids may be used ranging from 5 to 10%. In the maintenance phase this treatment can be rotated with the use of emollients only. Low potency TCS should be used on the face (with a mask). CONCLUSION: WWT using diluted steroids is a relatively safe addition to the therapeutic treatment options for children and adults with severe and/or refractory AD. Explanation and education is extremely important in the treatment of AD and WWT should only be employed by practitioners trained in its use. Specialized nursing care is essential, especially when using WWT for prolonged periods.

Efficacy and safety of 'wet-wrap' dressings as an intervention treatment in children with severe and/or refractory atopic dermatitis: a critical review of the literature.

BACKGROUND: During the last two decades wet-wrap treatment (WWT) has been advocated as a relatively safe and effective treatment modality in children with severe and/or refractory atopic dermatitis (AD). Unfortunately, there are still many unsolved issues concerning the use of wet-wrap dressings in patients with AD. OBJECTIVES: To make an inventory of the different methodologies and to evaluate the currently available evidence for the use of WWT as an intervention treatment in children with severe and/or refractory AD. METHODS: We performed a search of the literature via the online PubMed database. Reference lists from relevant articles were scanned for additional publications. Publications describing a treatment modality for children with severe and/or refractory AD, which included the application of wet dressings, were collected and evaluated using the guidelines of the NHS Centre for Reviews and Dissemination, University of York. RESULTS: Twenty-four publications were included for evaluation. Eleven of the publications detailed original clinical studies (study design level 2-4), while 13 revealed expert opinions (study design level 5). Evidence levels did not exceed level 4. CONCLUSIONS: Large prospective studies evaluating the efficacy and safety profile of WWT are lacking. We were able to formulate the following conclusions with a grade C of recommendation. (i) WWT using cream or ointment and a double layer of cotton bandages, with a moist first layer and a dry second layer, is an efficacious short-term intervention treatment in children with severe and/or refractory AD. (ii) The use of wet-wrap dressings with diluted topical corticosteroids is a more efficacious short-term intervention treatment in children with severe and/or refractory AD than wet-wrap dressings with emollients only. (iii) The use of wet-wrap dressings with diluted topical corticosteroids for up to 14 days is a safe intervention treatment in children with severe and/or refractory AD, with temporary systemic bioactivity of the corticosteroids as the only reported serious side-effect. (iv) Lowering the absolute amount of applied topical corticosteroid to once daily application and further dilution of the product can reduce the risk of systemic bioactivity.

The prevalence of positive reactions in the atopy patch test with aeroallergens and food allergens in subjects with atopic eczema: a European multicenter study.

BACKGROUND: The atopy patch test (APT) was proposed to evaluate IgE-mediated sensitizations in patients with atopic eczema (AE). OBJECTIVE: The prevalence and agreement with clinical history and specific IgE (sIgE) of positive APT reactions was investigated in six European countries using a standardized method. METHODS: A total of 314 patients with AE in remission were tested in 12 study centers on clinically uninvolved, non-abraded back skin with 200 index of reactivity (IR)/g of house dust mite Dermatophagoides pteronyssinus, cat dander, grass, and birch pollen allergen extracts with defined major allergen contents in petrolatum. Extracts of egg white, celery and wheat flour with defined protein content were also patch tested. APT values were evaluated at 24, 48, and 72 h according to the European Task Force on Atopic Dermatitis (ETFAD) guidelines. In addition, skin-prick test (SPT) and sIgE and a detailed history on allergen-induced eczema flares were obtained. RESULTS: Previous eczema flares, after contact with specific allergens, were reported in 1% (celery) to 34% (D. pteronyssinus) of patients. The frequency of clear-cut positive APT reactions ranged from 39% with D. pteronyssinus to 9% with celery. All ETFAD intensities occured after 48 and 72 h. Positive SPT (16-57%) and elevated sIgE (19-59%) results were more frequent. Clear-cut positive APT with all SPT and sIgE testing negative was seen in 7% of the patients, whereas a positive APT without SPT or sIgE for the respective allergen was seen in 17% of the patients. APT, SPT and sIgE results showed significant agreement with history for grass pollen and egg white (two-sided Pr > /Z/ < or = 0.01). In addition, SPT and sIgE showed significant agreement with history for the other aeroallergens. With regard to clinical history, the APT had a higher specificity (64-91% depending on the allergen) than SPT (50-85%) or sIgE (52-85%). Positive APT were associated with longer duration of eczema flares and showed regional differences. In 10 non-atopic controls, no positive APT reaction was seen. CONCLUSION: 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.

Treatment of refractory atopic dermatitis using 'wet-wrap' dressings and diluted corticosteroids: results of standardized treatment in both children and adults.

BACKGROUND: 'Wet-wrap' dressings with diluted corticosteroids form an alternative treatment in patients with refractory atopic dermatitis (AD). OBJECTIVE: To evaluate a standardized treatment, using wet-wrap dressings with diluted corticosteroids, in patients with refractory AD. METHODS: Results of treatment, complications and possible side effects were retrospectively evaluated in 14 children and 12 adults. RESULTS: Skin lesions improved dramatically during 1 week of inpatient treatment. A significant decrease in early-morning serum cortisol levels was measured. Levels below the normal range were only observed after 1 week in 2 adults and on day 4 in 3 children. Suppression of the hypothalamus-pituitary-adrenal-cortex axis in 1 adult and a new exacerbation of AD in 2 children and 3 adults complicated long-term treatment at home. Additional complications included folliculitis, a Pseudomonas aeruginosa infection, a secondary bacterial infection and refractory skin lesions between bandages. CONCLUSION: Wet-wrap dressings and diluted corticosteroids form an effective treatment in patients with refractory AD.