Vasculopathies, cutaneous necrosis and emergency in dermatology.

Most emergencies in dermatology comprise a variety of entities with a usually benign course. However, vasculopathies and vasculitis are not common, but they could represent respectively 1.9% and 4.4% of these entities according to some studies of Emergency Dermatology Department. They become an important disease which has to be identified early to establish appropriate management and treatment. Some of them are well known, such as the leukocitoclastic vasculitis, Schölein-Henoch, panarteritis nodosa, antineutrophil cytoplasmic antibody associated vasculitis, giant cell arteritis, cryoglobulinemic vasculitis and antiphospholipid syndrome. More frequent vasculopathies are livedoid vasculopathy, pigmented purpuric dermatosis and calciphylaxis. Less common ones are caused by interferon and cholesterol crystal embolization. Others are very infrequent as Degos disease and Sneddon Syndrome. Among the more recently described ones there are deficiency of adenosine deaminase type 2 and crystalglobulinemia. The other group is composed of vasculopathies associated to microorganism as infective endocarditis, septic vasculopathy, aspergillosis, fusariosis, strongiloidosis, ecthyma gangrenosum, lucio phenomenon of leprosy and necrotic arachnidism. Finally, among these entities we can also find diseases associated with proinflammatory stages as disseminated intravascular coagulation, myeloproliferative disorders, intravascular lymphoma, metastasis intravascular. When we face cutaneous lesions characterized by reticulated violaceous lesions, palpable purpura or cutaneous necrosis, a careful clinico-pathological correlation as well as some laboratory or radiological tests are mandatory to further delineate a diagnosis and a proper first line empirical treatment.

Metformin-Induced Generalized Fixed Drug Eruption With Cutaneous Hemophagocytosis.

Fixed drug eruption (FDE) consists of recurrent dusky-red to brownish macules or patches at the same sites after the readministration of the causative drug. It usually presents as a solitary lesion, but generalized eruptions have been described. The most frequently implied drugs are antibiotics, anticonvulsants, and analgesics. Only 2 cases due to metformin have been reported. Histopathologic features of FDE include vacuolar degeneration of the basal layer, necrotic keratinocytes, and superficial and deep perivascular lymphocytic infiltrate. Cutaneous hemophagocytosis in the context of a FDE has not been previously reported. We describe the case of an 86-year-old man who developed a pruritic generalized macular eruption of reddish to violaceous patches. Skin biopsy was performed and the dermal infiltrate was immunohistochemically studied. Histopathology showed interface dermatitis with vacuolar degeneration of the basal layer, necrotic keratinocytes, and superficial and deep perivascular lymphohistiocytic infiltrate. In deep dermis, histiocytes with engulfed cells inside their cytoplasm were seen. Lymphoid enhancer binding factor 1 immunostain demonstrated that most of these cells were lymphocytes. We present the first case with cutaneous hemophagocytosis in the context of a metformin-induced generalized FDE. In this particular case, hemophagocytosis was just a histopathologic finding with no systemic consequences for the patient.