Abnormal reticuloendothelial function in patients with active vasculitis and idiopathic membranous glomerulopathy. A study with 99mTc-labeled heat-damaged autologous red blood cells.

Reticuloendothelial function was assessed in 11 patients with systemic lupus erythematosus, 8 patients with Wegener's granulomatosus, and 20 patients with idiopathic membranous glomerulopathy by using autologous 99mTc-labeled heat-damaged red blood cells. With this method organ uptake could be measured by quantitative scintigraphy. There was no relation between the T1/2 of the blood disappearance curve and the T1/2 of the splenic uptake curve. The T1/2 of the blood disappearance curve was normal in all three patient groups. However, there was a significant shift from spleen to liver uptake in patients with active systemic lupus erythematosus, active Wegener's granulomatosus, and membranous glomerulopathy in comparison with a control group. There was no relation with age, level of circulating immune complexes, complement level, kidney function, or immunosuppressive treatment. We conclude that an increase of the liver component of reticulo-endothelial function may compensate abnormalities in splenic function. This stresses the importance of quantitative scanning to detect such abnormalities. The study provides evidence for disease related hyposplenism in patients with active systemic lupus erythematosus, active Wegener's granulomatosus, and membranous glomerulopathy.