Splenic platelet kinetics in systemic lupus erythematosus (SLE).

The splenic blood flow, intrasplenic platelet kinetics and spleen size were determined in 8 females with systemic lupus erythematosus (SLE), all without signs of active disease, by using gamma-camera scintigraphy with 111In-labelled platelets and 99mTc-stannous colloid. The results for splenic blood flow, intrasplenic platelet transit time and splenic platelet pool size, obtained by compartmental analysis of the initial distribution of radiolabelled platelets between blood and spleen, did not differ from those of a control group. In all SLE patients the spleen size was within normal limits. There was a significant relationship between the spleen volume and the splenic platelet pool size (r = 0.75; p less than 0.05), and between the spleen volume and splenic blood flow (r = 0.76; p less than 0.05). A borderline, inverse correlation was present between an estimate of splenic perfusion and intrasplenic platelet transit time (r = 0.62; p = 0.1). It is concluded that the splenic function, measured as splenic blood flow and intrasplenic platelet kinetics, is not disturbed in SLE patients without active disease.