Cutaneous histiocytic lymphangitis: an unusual manifestation of rheumatoid arthritis.

Two cases are presented of unusual cutaneous lesions associated with rheumatoid arthritis in underlying joints. The lesions were evanescent, erythematous and violaceous partly macular and partly indurated plaques, with a livedo-like pattern of erythema at the edge in one case. Histological changes were identical in the two cases. The major features were dilated, dermal lymphatics containing aggregates of inflammatory cells, mainly histiocytes, with adjacent perivascular lymphoid aggregates. An appropriate name for this reaction would appear to be cutaneous histiocytic lymphangitis.