Bee venom induces high histamine or high leukotriene C4 release in skin of sensitized beekeepers.

Histamine is the principal mediator released in the skin during immediate bee venom allergy but the significance of cysteinyl leukotrienes in these reactions is not known. We measured skin histamine and cysteinyl leukotriene release induced by bee venom in six sensitized beekeepers with the skin microdialysis technique. The skin was dialyzed for 2 h after skin prick test with bee venom, and the release of histamine and leukotriene C4 (LTC4) into the microdialysis fractions was measured. Leukotriene E4 (LTE) and methylhistamine excretion into the urine was assayed and whole blood histamine release test was performed. The release of histamine in the skin was variable: either high delayed, high immediate and delayed, weak release or no marked release. The histamine releasability in the skin correlated with that in whole blood. The three subjects with low histamine release exhibited high LTC4 release in the skin as well as high LTE4 excretion into the urine. Thus, the histamine and LTC4 releases were inversely associated with each other. These differences may explain the variation in the clinical reaction by bee stings in sensitized beekeepers.