Diffuse Dermal Angiomatosis: a Rare Cause of Painful Ulceration in Renal Insufficiency

Dear Editor, Diffuse dermal angiomatosis (DDA) is a benign, reactive cutaneous vascular proliferation. It represents a rare variant of cutaneous reactive angioendotheliomatosis, a benign condition characterized by hyperplasia of endothelial dermal cells and intravascular proliferation. In DDA, the endothelial proliferation affects mainly the reticular dermis. Clinically, DDA presents with erythematous to violaceous painful plaques that frequently evolve to necrosis and ulceration. Although the pathogenesis of DDA remains unknown, it has been classically associated with peripheral arterial disease. DDA has also been reported in the context of end-stage renal failure and it can be rarely associated with an arteriovenous fistula (AVF). Ormerod et al. previously reported the role of AVF in the pathogenesis of DDA and, to our knowledge, only two other similar cases have been reported. We report a fourth case of DDA associated with AVF. A 70-year-old man presented with a 1-month history of painful lesions on his left arm, which had been previously treated with empirical antibiotic therapy with clinical worsening. His medical history included end-stage renal disease under haemodialysis, a 1-year-old haemodialysis-related functioning AVF in the same lower arm, as well as diabetes mellitus, arterial hypertension, obesity and dyslipidaemia. On physical examination, erythematous plaques, with superimposed ulceration, were present on his left lower arm (Fig. 1a,b). The lesions were painful and the patient reported complete functional impairment, as he was not able to perform common everyday activities. No other subjective or objective clinical findings of arterial insufficiency were present. The patient had no fever and was otherwise well. Incisional cutaneous biopsies were taken for histopathological and microbiological analyses. Wound care was addressed, and progressively increasing analgesic therapy was required. Histopathological examination showed a diffuse, bandlike, vascular proliferation located in the superficial and mid dermis (Fig. 2a), consisting mainly of diffusely arranged endothelial cells forming small vascular lumina, some of which appeared dilated (Fig. 2b). Immunohistochemical stains for CD31 (Fig. 2c) and CD34 highlighted the vascular proliferation, while cytological atypia was absent. Periodic acid–Schiff and Ziehl–Neelsen stains were negative for the presence of microorganisms, and testing for human herpesvirus 8 was negative. These findings supported the diagnosis of DDA. A multidisciplinary approach resulted in closure of the AVF and a jugular vein catheter was placed for haemodialysis. After 7 weeks, almost complete clinical resolution was attained (Fig. 1c), and the patient only reported mild pain. The striking clinical resolution following prompt recognition of DDA with subsequent AVF reversal demonstrates the importance of correctly diagnosing DDA. If DDA is suspected, skin biopsy and vascular studies are of critical importance. Although mainly reported in association with atherosclerotic disease, DDA can occur in the setting of renal insufficiency and AVF, and the proposed pathogenesis is similar: local hypoxia increases vascular endothelial growth factor levels, causing endothelial cell proliferation. This cutaneous reactive pattern has also been reported in association with a variety of vaso-occlusive diseases. This pathogenesis supports the previous reports of complete clinical resolution after revascularization. The present case further demonstrates that accurate diagnosis is particularly rewarding, as correct therapeutic approach can be curative.