Extreme cutaneous histamine sensitivity with hay fever and increased IgE concentrations in an unselected population.

Cutaneous sensitivity to histamine, responses to prick tests with allergens, and serum IgE concentrations were measured and hay fever assessed by questionnaire in an unselected population to determine whether increased sensitivity to histamine is an independent phenomenon contributing to allergic disorders or may be caused by allergic reactions. Increased cutaneous sensitivity to histamine was strongly associated with an increased number of positive responses to prick tests, high serum concentrations of IgE, and hay fever. This new test is simple, cheap, applicable to schoolchildren, and provides useful information.