An inflammatory process that develops secondary to trauma, usually in the form of a penetrating injury or rupture of a follicle, and that proceeds through stages of granulation tissue with numerous extravasated erythrocytes, granulomatous inflammation, and fibrosis.
A malignant nonepithelial neoplasm (a sarcoma) presumably of perineural fibrocytes that presents itself usually on the trunk, but sometimes elsewhere, such as the extremities, face, and scalp.
An inflammatory disease characterized by lesions with arcuate, annular, and serpiginous outlines and by collarettes of scale on the inner margin of lesions that extend outward in centrifugal fashion, disappearing in months as a rule in the absence of treatment.
An inflammatory process that tends to involve mucous membranes, as well as skin, and of the latter the acra especially.
An inflammatory process, i.e., a panniculitis, marked by tender erythematous plaques, nodules, or tumors (or combinations thereof) that usually affect the anterior aspect of the legs and, less often, the arms, and induced by processes, in an organ other than the skin, as dissimilar as sarcoidosis, Crohn’s disease, and histoplasmosis.
A hamartoma of mostly follicular elements that presents itself clinically as a firm, skin-colored papule.
Infundibulitis, usually a suppurative inflammatory process that involves infundibula, is either noninfectious, as in the case of pustules of acne vulgaris, or infectious, as in the case of pustules caused by Staphylococcus aureus.