Pulse granuloma of the lip: morphologic clues in its differential diagnosis

Pulse granuloma is not a common condition in cutaneous pathology. In diagnosing this condition, it is essential to determine if the foreign fragmented bodies are really vegetable parts. Certain vegetable structures, such as hyaline rings, have been clearly emphasized in the literature. However, other vegetable parts can show certain morphologic similarities with animal structures, especially if observed in a fragmented biopsy, as is the case with the pericarp (which can mimic the cuticle of a maggot) or the endosperm (which can mimic the fat cells of the larva). Herein, we present a case of pulse granuloma involving the lip, an uncommon location for this condition. We also describe the histopathologic appearance of experimentally obtained maggots and pupae, as well as that of several vegetable seeds. We compare some of the vegetable and animal structures and emphasize the differential diagnosis between them.