A 46-year-old female asthmatic developed vegetating iododerma with pronounced eosinophilia secondary to the ingestion of potassium iodide. Serological studies, including precipitin in gel, indirect passive hemagglutination, and passive cutaneous anaphylaxis failed to demonstrate the presence of circulating antibody. Intradermal tests with potassium iodide, normal saline, human serum albumin, iodinated I 131 serum albumin, and human serum albumin incubated with potassium iodide were negative for both immediate and delayed reactivity. The patient's lymphocytes in culture underwent blastogenic transformation, measured morphologically, when exposed to iodinated I 131 serum albumin. Thyroxine, potassium iodide alone, human serum albumin, and human serum albumin incubated with potassium iodide failed to induce transformation. The findings are in accord with the concept that iodides may act as haptenes by combining with serum protein and suggest that allergic hypersensitivity plays a fundamental role in vegetating iododerma.
Rosenberg FR, Einbinder J, Walzer RA, Nelson CT. Vegetating IododermaAn Immunologic Mechanism. Arch Dermatol. 1972;105(6):900-905. doi:10.1001/archderm.1972.01620090070016