Post-surgical pyoderma gangrenosum: a clinical entity.

Post-surgical pyoderma gangrenosum (PSPG) represents a specific entity: it shares some clinical aspects of pyoderma gangrenosum (PG), but has a series of its own features. In this paper, two cases of PSPG associated with breast surgery are presented: their analysis, combined with a review of the few other cases reported in the literature, show the particular clinical presentation and evolution of this condition. Firstly, the onset of PSPG follows a sequence. After an apparently normal evolution of scar formation following a surgical procedure, the scar presents with many small dehiscences, which will progressively coalesce to some larger areas of wound ulceration, with no visible granulation tissue. Secondly, the delay between surgery and the beginning of symptoms is variable, from 4 days to sometimes 6 weeks. The process will evolve well beyond what would be expected for the initial wound that was created by surgery, with no self-limitation. The skin ulcerations become larger, despite any local treatment or antibiotics. Thirdly, PSPG can affect any anatomical location with the exception of the nipple-areolar complex. Fourthly, a dramatic response to immunomodulatory drugs will be observed. The pain is an inconstant symptom. Present in the first week after surgery, it can be severe and disproportionate regarding clinical presentation.