مقايسه ي ارزش تشخيص عصاره ي گياه سلمه تره (كنوپود) وعصاره ي مشابه استاندارد با آزمون پوستي پريك در ايجاد واكنش پوستي

Comparing Iranian & Standard Allergen Extracts of Chenopodium Album by Skin Prick Test

Background: Skin test using a pure and sterile extract proper allergen subtances is one of the most sensitive and important procedures for the diagnosis of environmental allergic agents. However, these extracts are expensive and always are not available. This study was conducted to compare the Iranian and French (Standard) extracts of chenopodium album by Prick skin test in Tehran Children Medical Center in 2002. Materials and Methods: This analytical double blind study was conducted on 100 volunteers (aged 20-58: 54 males , 46 females). Patients who had a severe disease, atopy or taking antihistamins or anticonvulsants were excluded from the study. All the patients, had positive histamin tests. Patients who showed an skin inflation more than 4 mm in diameter considered as positive control and patients who showed no reaction were considered as negative control. Three different dilutions of both extracts were tested in Prick procedure on ulnar area of both arms by a physician. Kind of reaction such as inflation and redness was observed and noted after 20 minutes. Inflation more than 3mm associated with redness around it was considered as a positive reaction. Results: In the study none of the subjects had positive reaction in 100-fold dilution of extracts. In 10-fold dilutions 4 positive reactions (diameter 3-6 mm), and 6 positive reactions (diameter 3-5 mm) with the standard and Iranian extracts were observed respectively. On the other hand, 17 positive reactions (3-10 mm) and 22 positive reactions (3-10 mm) with the Standard and Iranian undiluted extracts were observed respectively. The specificity and sensitivity of the Iranian undiluted extract was 92.7% and 94% respectively and the correlation coefficient between the two extracts was 0.78. Conclusion: Due to the high The sensitivity and specificity of the Iranian extract and the degree of concordance between these two it can be suggested that the Iranian extract can be substituted for the standard extract. The use of undiluted Iranian extract is recommended.