An Overview of Panniculitis – A Diagnostic Challenge for Dermatologists and Pathologists

": The term ""panniculitis"" refers to a heterogeneous group of conditions that involve inflammation of the subcutaneous cellular tissue. Although there is no universally accepted classification of panniculitis, to facilitate the diagnosis, they were divided into two large classes, based on the histopathological criteria: predominantly lobular and predominantly septal panniculitis. Depending on the presence or absence of vascular damage, each of the two classes mentioned above is divided in turn into panniculitis without vasculitis and panniculitis with vasculitis. The diagnosis of various types of panniculitis can sometimes be very difficult, due to the histopathological changes that occur in the various evolutionary stages of the lesions. Thus, the positive diagnosis relies on the corroboration of clinical data, histopathological examination, and ancillary laboratory tests. We provide an overview of the clinical and histopathological features of panniculitis, classified according to the histopathological criteria. "