Immune deposits in oral mucosa, skin and kidney in patients with systemic lupus erythematosus.

Biopsies were obtained simultaneously from normal oral mucosa, sun-protected and sun-exposed skin in patients with suspected or diagnosed systemic lupus erythematosus, in order to compare the deposition of immunoproteins. In patients with renal involvement a kidney biopsy was also studied. Immunofluorescence findings at the connective tissue-epithelial junction (lupus band test) showed a good correlation between keratinized oral mucosa and sun-protected skin in 18 sets of biopsies while sun-exposed skin frequently showed more immune reactants. No close connection could be found between the deposition of immune reactants in skin/mucosa and kidney. It is concluded that diagnostic use of the lupus band test performed on normal mucosa has the same value as that on sun-protected skin.