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991.
Lazarov A 《Contact dermatitis》2006,55(2):73-76
The results of a 7-year retrospective study (1998-2004) from patch testing with the European Standard Series (ESS) establishing the frequency of sensitization in a contact dermatitis clinic in Israel are presented. 23 allergens were patch tested on 2156 patients, 1462 females (67.8%) and 694 males (32.2%). Atopy and asthma were present in 21.9% of the patients. One or more allergic reactions were observed in 937 patients (43.5%). The highest yield of patch test positives from the 1076 positive reactions were obtained from nickel sulfate (13.9%), fragrance mix (7.1%), potassium dichromate (3.8%), Balsam of Peru (3.6%), CL+Me-isothiazolinone (3.4%) and cobalt chloride (3.4%). Allergens which produced the least amount of positive results were primin and clioquinol. Allergic contact dermatitis (ACD) was established in 32.8%, whereas occupationally related allergic (8.0) and irritant contact dermatitis (5.6%) affected a total of 13.6% of the cases studied. The most common clinical forms of dermatitis were chronic dermatitis (47.7%) followed by acute dermatitis (22.8%), and lichenification and hyperkeratosis (7.9%). The hands (30.7%), face and neck (23.9%) and extremities (11.3%) were the most frequently affected areas. Four allergens in our study differed from the top 10 allergens in Europe namely: Cl+Me-isothiazolinone, formaldehyde, 4-tert-butylphenol formaldehyde resin and sesquiterpene lactone mix reflecting an existing difference in environmental exposure. Our study is the first to provide data on the frequency of sensitization and important allergens in the aetiology of ACD in Israel. In spite of the existing differences with Europe, we conclude that ESS is an appropriate screening system for the diagnosis of ACD in Israel. 相似文献
992.
Sporadic cases of contact allergy to white petrolatum, which is used as a vehicle in patch test preparations, have been reported. The quantitative relevance of the phenomenon remains yet to be elucidated. Methods: Retrospective analysis of patch test data of the Information Network of Departments of Dermatology (IVDK, http://www.ivdk.org) between 1992 and 2004. Results: Analysis of 79 365 patients patch tested with pure petrolatum yielded 27 '+' (0.03%) and 2 '+++' (0.003%) reactions. The majority of non-negative reactions (0.3%) was interpreted as doubtful (235) or mild irritant (32). The negative reaction index (RI) (-0.8), and the high positivity ratio (PR) (93%) especially a lack of concordance with patch test preparations containing > or=99% petrolatum indicate that many of the 'positive' (+) reactions have to be considered as irritant. There were 2 '+++' reactions. In 1 case, an 'angry back reaction' was confirmed. The other case is probably a reading or documentation error, as the majority of patch test reactions to preparations containing petrolatum remained negative in this case also. Conclusions: True allergic patch test reactions to white petrolatum are extremely rare and probably due to an individually increased susceptibility to allergens and/or irritants. This is in agreement with considering petrolatum as a non-sensitizer. 相似文献
993.
994.
995.
Miconidin and miconidin methyl ether from Primula obconica Hance: new allergens in an old sensitizer
Several chemical and clinical observations have suggested the presence of at least one more allergen in addition to primin in Primula obconica. The aim of this study was to investigate the allergenicity of the primin precursor miconidin and the related miconidin methyl ether, both isolated from P. obconica. 12 primin-positive persons were patch tested with miconidin 0.01% petrolatum (pet.), miconidin in 96% ethanol incorporated into 0.01% pet., and miconidin methyl ether 1.0% pet. All persons were positive to miconidin 0.01% pet., with the strength of reactions very similar to those of the individual primin reactions, and remained inexplicably negative while testing with miconidin in 96% ethanol and pet., while miconidin methyl ether elicited 7 positive reactions. Although both miconidin and miconidin methyl ether may be allergenic only due to their conversion to primin in the skin, the presence of these substances nevertheless has to be taken into account when assessing the allergenicity of new P. obconica cultivars. 相似文献
996.
997.
Rygl M Pycha K Stranak Z Melichar J Krofta L Tomasek L Snajdauf J 《Pediatric surgery international》2007,23(1):27-31
The purpose of this study was to evaluate the outcome in neonates with congenital diaphragmatic hernia (CDH) either presenting
within the first 24 h of life or diagnosed prenatally. The study was particularly focused on the time of onset of respiratory
distress and on the use of the Gore-Tex (GT) patch for diaphragmatic reconstruction. Records of 104 neonates with CDH were
retrospectively reviewed. The data were analyzed by ANOVA, Kruskal–Wallis test or χ
2 test as appropriate. The result showed that the overall survival rate was 73.1% (76/104). Survival of operated neonates was
91.6% (76/83). Postnatally diagnosed neonates with the onset of respiratory distress within the first minute of life survived
in 67%, with the onset between 2 and 10 min survived in 89%, whilst neonates with the onset of respiratory distress after
l0 min survived in 100% (P = 0.007). Birth weight, gestational age, time of onset of respiratory distress and Apgar score significantly differed between
survivors and nonsurvivors. Primary closure of the diaphragmatic defect was performed in 62 patients while the GT patch was
used in 21 patients. The survival of patients with a large defect treated with a GT patch was lower (76.2 vs. 96.8%, P = 0.003). There was only one case of recurrence in our series with the GT patch. Survival depends on the time of onset of
respiratory distress and size of the defect, both of which correlate with the degree of pulmonary hypoplasia. The term high-risk
CDH is appropriate only for children with respiratory distress within the first 10 min of life and those diagnosed prenatally.
The GT patch is a suitable material for the diaphragmatic reconstruction; we suppose that the recurrence is caused by incorrect
attachment of the patch to the thoracic wall. 相似文献
998.
Previous studies have shown that the prevalence of specific allergens varies by geographic area, population, age and sex. The objective of the present study was to determine the relative frequency of positive reactions to different sensitizers in Israeli patients with clinically suspected contact dermatitis (CD) and to identify possible sex and age differences. A total of 943 consecutive patients were tested for CD using the European standard patch test series. The most frequent allergen was nickel sulfate followed by potassium dichromate and fragrance mix. Positive reactions to nickel sulfate were more common among women, especially those in the younger age group (younger than 40 years). Positive reactions to balsam of Peru were more common among men, especially those in the older age group (40 years or older). This study presents the result of the standard patch test in Israel with stratification according to age and sex. The findings of the present study, combined with reports on geographic/population differences in the prevalence of specific allergens in CD, indicate the need for further investigations to identify prominent local allergens for better adaptation of the standard patch test to local needs. 相似文献
999.
Jowsey IR 《Contact dermatitis》2007,56(6):305-310
Risk assessment serves to ensure that dermal exposure to skin sensitizers does not result in the acquisition of allergic skin disease. Traditionally, the approach adopted was one of comparative analysis, involving benchmarking against other allergens of known potency. More recently, efforts have been made to embrace a quantitative risk assessment (QRA) approach. However, the accuracy of any risk assessment is reflected in the extent to which it meets the fundamental objective stated above. Thus, clinical experience is of key importance. There exists the possibility for the originators of risk assessments relating to chemicals that possess skin-sensitizing potential to work directly with the clinical community to proactively obtain this experience through specific surveillance programmes. This forms the focus of this review article. The current status of the QRA approach is considered initially. A recently published example of one such surveillance programme that was undertaken as a collaborative initiative between industry and the clinical community is then reviewed. Finally, a possible strategy for the future is presented, in which it is suggested that surveillance strategies might be deployed in certain situations as an adjunct to the initial risk assessment. It is hoped that such a framework might further improve the efficacy of future approaches to skin sensitization risk assessment. 相似文献
1000.
BACKGROUND: Experimental sensitization depends upon the amount of allergen per unit skin area and is largely independent of the area size. OBJECTIVES: This study aimed at testing if this also applies for elicitation of nickel allergy. PATIENTS/METHODS: 20 nickel allergic individuals were tested with a patch test and a repeated open application test (ROAT). Nickel was applied on small and large areas. The varying parameters were area, total dose and dose per unit area. RESULTS: In the patch test, at a low concentration [15 microg nickel (microg Ni)/cm(2)], there were significantly higher scores on the large area with the same dose per area as the small area. At higher concentrations of nickel, no significant differences were found. In the ROAT at low concentration (6.64 microg Ni/cm(2)), it was found that the latency period until a reaction appeared was significantly shorter on the large area compared to the small area. It was also found that the ROAT threshold (per application) was lower than the patch test threshold. CONCLUSION: For elicitation of nickel allergy, the size of the exposed area and therefore the total amount of applied nickel, influence the elicitation reaction at some concentrations, even though the same dose per unit area is applied. 相似文献