Pseudo-Kaposi sarcoma

A 39-year-old woman was admitted to the clinic in September 2017 due to exanthema found on lower legs. The patient could not specify when the first skin lesions appeared. Concurrent diseases include schizophrenia.
Physical examination confirmed bilateral extensive lesions on lower legs with blue and scarlet papulae merging into bigger plaques; they were initially covered with papillary buildup (fig. 1). Shallow ulceration on the extensor surface of a lower leg. Laboratory test results did not show any deviations from reference values.
Serum test for HIV antibodies and p24 antigen was negative. Doppler ultrasound of lower limb veins revealed venous insufficiency and signs of postphlebitic syndrome. A sample of nodular exanthema was taken for histopathological examination. The biopsy showed a regular pattern of blood vessel proliferation, fibroblasts, extravasated erythrocytes, and hemosiderin deposits in dermis. Neither atypical cells nor endothelial vascular cracks were identified. Immunohistochemical analysis using monoclonal antibodies against CD34 antigen confirmed a positive reaction within endothelial cells of blood vessels, and a negative one within pericytes, what in turn confirmed the diagnosis of pseudo-Kaposi sarcoma (acroangiodermatitis). Implemented treatment involved compression therapy and topical corticosteroids, and 0.25% of silver nitrate solution for ulcers. After a week, a remission of erosive lesions was achieved; skin lesions were still present, although less intense (figs. 2 A, B).
Acroangiodermatitis (AAD), also referred to as pseudo-Kaposi sarcoma, is a vascular-proliferative disease characterized by reactive proliferation of small blood vessels in response to congenital or acquired vascular lesions. The changes initially appear as limited, slow-growing, red, purplish or dark macules, papules or plaques, which over time become papillary, and can also form ulcers. There are four clinical variants of AAD, the most common type: 1) Mali is associated with venous hypertension; 2) the Stewart-Bluefarb type is associated with congenital arteriovenous malformation (AVM); 3) there is also a less frequent one in patients with chronic renal failure with acquired arteriovenous fistula; and 4) a form occurring in pregnant women.
Mali et al. for the first time introduced the term acroangiodermatitis in 1965. Eighteen patients with purple and red speckles and papulae mostly on dorsal surface of feet with chronic vascular...


View full text...