[Recent developments in the field of non-allergic dermatosis].

There is no sharp borderline between allergic and non-allergic dermatoses since immunology is involved in nearly all cutaneous diseases. On the other hand, immunological reactions are influenced by external factors like solarium exposure, bereavement, and especially therapy. Immunological reactions may cause metabolic disorders like hyperthyreosis, exophthalmus and pretibial myxedema, on the other hand, metabolic disorders may impair immunological defense. GVHD causes skin reactions like lichen planus or circumscribed scleroderma. With most dermatoses, the question concerning the importance of immunological findings in a given disease remains open: Are they cause or result?