Granulomatous annular diseases.

Granulomatous skin disorders comprise a large group of diseases that are typically characterized by granuloma formation both in the skin and in many other tissues. Cutaneous lesions are usually seen as erythematous papules and plaques that may occasionally be arranged in an annular, ringlike configuration. The etiopathogenesis is unclear in most cases, and granuloma formation may be associated with various systemic, infectious, and metabolic disorders, foreign bodies, environmental antigens, or malignancies. Treatment options are dependent on the etiology, extent, and severity of the lesions. This review includes the clinical, histopathologic, and dermatoscopy findings, differentials, and treatment options for noninfectious granulomatous annular skin disorders.