Abstract
The skin prick test (SPT) is a useful examination to detect the antigen in a pediatric allergic disease. Its disadvantages are non-specific response due to vasoactive substances such as histamine, choline and monoamine included in the allergen extract. In this study, the histamine and choline concentrations in 49 allergen extracts were measured. Additionally, histamine concentrations in 26 raw food items and choline concentrations in 33 raw food items were determined. The subjects were 30 atopic patients on whom the SPTs were performed. A SPT was performed according to the guidelines of the Scratch test Study Group. It has been suggested that histamine solution (1 mg/ml, 10 mg/ml) should be tested as a positive control in the SPT. The Radioallergosorbent tast (RAST) was also performed in these patients. Histamine concentrations of the house dust, mite, egg white and milk extracts were low, and high correlation was seen between SPT and RAST. However the histamine concentration in fruit, vegetable and fish extracts were higher. Positive SPT result did not correlate well with the patients' history nor with RAST. Choline concentrations of vegetable and fish extracts were also high, but in the SPT, the wheal and flare reactions were absent or small by choline. This study indicates that vasoactive substances, especially histamine, should be useful in positive control tests for the SPT, but choline is not.
