[Clinical, histological and immunohistochemical aspects of "severe hypodermatitis"]

In the recent decade, two novel nosological entities among the group of panniculitis have clinically been elaborated, i.e., panniculitis associated with alpha 1-antitrypsine deficiency and histiocytic cytophagocytic panniculitis (Winkelmann). Both entities are rare and hardly aware to clinicians and pathologists till now, since they have probably been reckoned with the frame of Pfeifer-Weber-Christian's disease before. There are established reasons to qualify both syndromes as "severe" types of panniculitis, due to their prognostic uncertainty bearing the peril for fatal outcome. In this study, twelve cases of severe panniculitis cared for by the Dermatological University Department of Erlangen since the eighties, have been analyzed including two cases presenting with panniculitis of facticious or myelodysplastic origin, respectively. Based on the literature as well as clinical, histological and immunohistochemical reexamination of our cases, the significance of alpha 1-antitrypsine deficient panniculitis was considered, yet the enzymatic influences on the pathogenesis of this type of panniculitis are a matter of dispute so far. It is also questionable whether the clinical pattern of histiocytic cytophagic panniculitis that is linked with the syndrome of generalized haemophagocytosis represents, at least for distinct cases, a peculiar type of paraneoplastic inflammatory reactivity in fatty tissues, with MAC387+ phagocytic cells and UCHL1+ infiltrative cells. Since haemophagocytosis can be observed in various stages and subtypes of severe panniculitis, this phagocytic phenomenon obviously does not represent a specific marker of malignancy, but indicates a generalized disorder of the histo-phagocytic system running an often pernicious course.