Chrysiasis: transmission electron microscopy, laser microprobe mass spectrometry and epipolarized light as adjuncts to diagnosis.

Two patients receiving gold therapy for rheumatoid arthritis developed skin pigmentation, chrysiasis, which in one appeared 4 months after cessation of the therapy. The diagnosis was confirmed by transmission electron microscopy and mass spectrometry laser microprobe analysis of paraffin sections and its extent demonstrated by epipolarized light. The condition is poorly reported and clinically may be confused with silver and mercury impregnation. Tissue diagnosis requires ancillary methods and of these, transmission electron microscopy and laser microprobe mass spectrometry are excellent examples. The transmission electron microscopy findings differ from previous reports and raise doubts on the hypothesis on the role of the skin in gold excretion. Because of the renewed interest in crysotherapy and the latent period that can separate this from chrysiasis, an increase in chrysiasis and the need for its diagnosis can be anticipated.