Evidence for macrophage activation in dialysis patients exposed to silicone filing.

Spleen cell suspensions of 2 dialysis patients with hepatosplenomegaly and pancytopenia were studied in vitro. Spleen cells of a cadaver kidney donor were studied as control. In spleen macrophages of the patients, silicone particles could be demonstrated with TEM and electron microprobe analysis. Under basal conditions and after stimulation with zymosan and concanavalin A, release of PGE2, TXB2 and 6-keto-PGF1 alpha from patient cells was higher than control cells. This anecdotal observation parallels previous animal studies and suggests that loading of human macrophages with foreign material particles activates arachidonic acid metabolism.