Plasma exchange for kidney disease: what is the best evidence?

Therapeutic plasma exchange (TPE) has been used as adjunctive therapy for various kidney diseases dating back to the 1970s. In many cases, support for TPE was on mechanistic grounds given the potential to remove unwanted large molecular-weight substances such as autoantibodies, immune complexes, myeloma light chains, and cryoglobulins. More recently, growing evidence from randomized controlled trials, meta-analyses, and prospective studies has provided insights into more rational use of this therapy. This report describes the role of TPE for the 6 most common kidney indications in the 2013 Canadian Apheresis Group (CAG) registry and the evidence that underpins current recommendations and practice. These kidney indications include thrombotic microangiopathy, antiglomerular basement membrane disease, anti-neutrophil cytoplasmic antibody-associated vasculitis, cryoglobulinemia, recurrence of focal and segmental glomerulosclerosis in the kidney allograft, and kidney transplantation.