A guide to annular eruptions

Many skin disorders produce lesions with particular shapes or patterns. The term ‘annular’ describes lesions that appear as open circles or in a ring-like configuration. They are seen in many dermatoses and may lead to a certain diagnosis or to a specific differential diagnosis. Diagnostically, it is important to qualify the description of annular lesions, particularly with regard to their evolution and to the presence of scaling. It should be noted, however, that recent topical applications may conceal scaling.