MARY S.STONEMDSOONBAHRAMIMDCARRIE ANN R.CUSACKMDSENAIT W.DYSONMDMOLLY A.HINSHAWMDVINCENTLIUMD
The skin biopsy specimen revealed a superficial and deep perivascular lymphoplasmacytic infiltrate. There were ectatic lymphatics throughout the dermis, some with intraluminal aggregates of CD68-positive histiocytes. Because of the prominent plasma cells, Lyme antibody titers were obtained and were negative. Patch testing with a 29-allergen panel (including joint components obtained from the manufacturer) showed only thimerosal reactivity, which was thought to be clinically insignificant. Empirical treatments with fluocinonide cream, cephalexin, doxycycline, low-dose prednisone, and intra-articular steroid injection were ineffective.
Erythematous Patch Overlying a Swollen Knee—Diagnosis. Arch Dermatol. 2010;146(9):1037-1042. doi:10.1001/archdermatol.2010.218-b