[Concentration of gold in macrophages of the bone marrow in rheumatic diseases subjected to chrysotherapy].

Ultrastructural investigation of bone marrow cells of histiocytic lineage to determine the presence of microcrystals containing gold was carried out in 12 patients. Eleven patients had classical or definite rheumatoid arthritis and one had palindromic rheumatism; the duration of these diseases ranged from 6 months to 10 years. Two patients had never received chrysotherapy and therefore served as controls. The remaining 10 patients had been treated with sodium aurothiopropanolsulfonate for periods ranging from 1 week to 4 years and 4 months without any clinical signs of laboratory findings--hematological changes in particular--of drug intolerance. No crystalline structures could be found in the 2 controls or in the patient who had just begun treatment. Conversely, in the 9 other patients, the lysozymes of bone marrow macrophages contained needle-like microcrystals containing one atom of gold for two atoms of sulfur, i.e. identical in proportion to the injected product. For equivalent total doses, deposits appeared to be equally numerous regardless of the time span between the last injection and the sampling (2-21 months). These crystals were present in the bone marrow several years after the beginning of chrysotherapy. The actual mechanism of their precipitation remains unknown at present.