Parameters for indication of plasmapheresis and the interpretation of results.

Plasmapheresis has been employed in the treatment of various immunological disorders, and its efficacy has mainly been attributed to the removal of humoral factors. Besides these effects, plasmapheresis may induce some modifications to the cellular immunological status, contributing to the restoration of altered immunological function. In immunological renal diseases various parameters may be followed to decide the use of plasmapheresis, and to judge the effect of treatment. They include clinical, functional, and morphological investigations. In patients with lupus nephritis the main indications for plasmapheresis are the presence of impaired renal function and histological signs of activity in renal biopsy. In these patients plasmapheresis is able to modify humoral and cellular immunological abnormalities. Renal function and clinical course may improve in most cases. In patients with arteritis and acute renal failure the response to plasmapheresis combined with immunosuppressive drugs is better than the response to drug therapy alone. In acute renal transplant rejection plasmapheresis may be of value in improving the graft prognosis, when humoral factors are demonstrable in the pathogenesis of graft damage and vascular lesions are present in the kidney.