A reticulate vascular abnormality in patients with lymphoedema: observations in eight patients.

We describe eight patients with lymphoedema who had prominent compressible ridges of tissue in a reticulate pattern, situated predominantly on the upper part of the lower leg. In five patients the lymphoedema was primary, two patients had circumferential venous ulceration, and one had marked venous disease with a small ulcer. One patient had a squamous cell carcinoma of the medial thigh and dysplastic keratoses in the distribution of the reticulate ridges. In three of the four cases in whom histological examination of the ridges was performed, the skin at these areas was demonstrated to contain grossly dilated angular vessels in the mid-dermis, many with valves visible. The vessel walls had a single layer of endothelial cells (anti-factor VIII-related antigen positive) and a basement membrane containing type IV collagen. Abnormal elastic tissue in these biopsies was similar to that in erythema ab igne. Indirect lymphography in one case did not demonstrate dilated lymphatic vessels. The body site distribution and clinical pattern of the abnormality appeared to be similar to erythema ab igne but associated with an underlying abnormality of lymphatic rather than blood vasculature. We propose that our cases may represent 'lymphoedema ag igne'.