[New advances in contact allergology]

In October 1996, dermatologists commemorated the centenary of the Patch test that Jadassohn had developed in 1896 at Breslau. A great amount of scientific information came to light in the following years due to progress in immunology applied to dermatology. To consider the most important recent advances in the field of contact allergic dermatitis, it is necessary to recognise the role of adhesion molecules specific for antigen presenting dendritic cells, also keratinocytes as antigen presenting cells, the importance of CD8 cells, IL10, IL12 and IL1 and their role in modulation of the contact allergy reaction. The chemistry of haptens should lead to a decision as to whether a new molecule is allergic or not, as well as the different possibilities of bonding to form sensitizing complexes. Epidemiology and the present development of epicutaneous tests are at the centre of studies that are mentioned in this general review.