Concepts in Cutaneous Vasculitis

Skin biopsy plays a fundamental role in the diagnosis of vasculitis. However, the general pathologist or dermatopathologist who encounters these diagnostic findings in their early stages often faces the paradox that the clinician requests the exclusion of various systemic diseases, when the biopsy only shows leukocytoclastic vasculitis. In other cases, even though the affected vessels are small, some of them seem deep within the biopsy, raising differential diagnosis with several entities of systemic repercussion. Lastly, although the dermatopathologist has a histological picture before them, they are often required to correlate it with laboratory data such as the presence of antineutrophil antibodies, for example. Therefore, the objective of this article is conceptual, emphasizing those basic aspects that can contribute to a better understanding and diagnosis of skin biopsy in vasculitis.