Using a skin perfusion method a pharmacological substance, previously unrecognised in allergic contact eczema, has been recovered. This substance, obtained from eczematous skin in 15 of 22 patients was not due to histamine, kinins, serotonin, or acetyl choline. Its solubility in ethyl acetate indicates that it is a fatty acid. Histamine was found in three and kinin in seven of the 22 patients. The specificity of these findings in relation to allergic contact eczema requires further investigation.
Greaves MW, Søndergaard J. A New Pharmacological Finding in Human Allergic Contact Eczema. Arch Dermatol. 1970;101(6):659-661. doi:10.1001/archderm.1970.04000060031007