Morphology of rare exogenous materials in dermatopathology

Dermatopathologists are occasionally challenged by exogenous materials found in their biopsies. Recognition of most of the structures and morphological parts of foreign materials is not always easy because most of the literature thus far has focused on the study of the histological and histopathological aspects of human tissues, as well as on the granulomatous response elicited by such foreign bodies. However, there are some cases of rare exogenous material in biopsies, mainly published as case reports; and dermatopathologists often lose precious time searching for information about such cases. In this article, we examine the morphology of the following elements: alimentary detritus, cacti barbs, cotton fibers, silica particles, nail polish, maggots, sea urchin spines and honey bee stings.