Allergic contact eczema is a T cell-mediated immune response, often referred to as a type IV allergy. Haptens in the skin are transported by Langerhans cells and presented to CD4 and CD8 positive T...

Systemic treatment, usually with tetracyclines, often in combination with local treatment, is necessary in moderate to severe acne. If this has no effect, especially with severe and scar-forming acne...