title: Histopathologic patterns associated with external agents.
abstract: A large number of foreign substances may penetrate the skin for both voluntary and involuntary reasons. The voluntary group includes the particulate materials used in tattoos and cosmetic fillers, whereas the involuntary group is almost always caused by accidental inclusion of external substances secondary to cutaneous trauma. This article focuses on the histopathologic findings seen in cutaneous reactions to exogenous agents, with special emphasis on the microscopic morphology of the external particles in recognizing specifically the involved substance (something that is becoming increasingly important in the event of litigation).
authors.affiliation: Department of Dermatology, Fundación Jiménez Díaz, Universidad Autónoma, Avenida Reyes Católicos 2, Madrid 28040, Spain. lrequena@fjd.es
authors.forename: Luis
authors.initials: L
authors.lastname: Requena
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Cerroni
authors.forename: Heinz
authors.initials: H
authors.lastname: Kutzner
mesh_terms: D000279:Administration, Cutaneous; D004396:Coloring Agents / Q000009:adverse effects*; D003357:Cosmetic Techniques; D003879:Dermatologic Agents / Q000009:adverse effects*; D003875:Drug Eruptions / Q000209:etiology / Q000473:pathology*; D064420:Drug-Related Side Effects and Adverse Reactions; D015745:Granuloma, Foreign-Body / Q000139:chemically induced* / Q000473:pathology*; D006801:Humans; D007279:Injections, Subcutaneous; D008670:Metals / Q000009:adverse effects; D008903:Minerals / Q000009:adverse effects; D004364:Pharmaceutical Preparations / Q000008:administration & dosage; D013653:Tattooing / Q000009:adverse effects
chemical_list: D004396:Coloring Agents; D003879:Dermatologic Agents; D008670:Metals; D008903:Minerals; D004364:Pharmaceutical Preparations