Effects of plasma-protein A immunoadsorption on idiopathic nephrotic syndrome recurring after renal transplantation

Patients with end-stage renal failure secondary to idiopathic nephrotic syndrome are at risk of initial disease recurrence after kidney transplantation (30%). Selective proteinuria can appear immediately after transplantation and focal glomerular sclerosis with graft loss can occur in 10% of patients with recurrence. Current immunosuppressive protocols do not seem to influence the recurrence rate in adult patients and the efficacy of therapeutic plasma exchanges remains controversial. We have previously demonstrated that plasma exchanges, proposed early before glomerular sclerosis, were able to significantly reduce proteinuria without affecting albuminemia or glomerular filtration. We report here on three patients who suffered immediate recurrence after transplantation and were treated with plasma immunoadsorption onto protein A column (Excorim, Lund); these patients had prior histories of steroid-resistant focal glomerular sclerosis. This procedure is more specific than plasma exchange in that it cleared the serum of immunoglobulins, significantly decreased proteinuria in only two cases (from 14 to 5 g/d and 2.5 to 0.8 g/d) and eliminated it in the third case (from 3 to 0.1 g/d). The modifications of proteinuria levels appeared as early as the second immunoadsorption sequence and returned to pre-immunoadsorption values within 2 to 8 weeks. These observations argue for the protein A binding of plasmatic factor(s) involved in idiopathic, nephrotic syndrome and allow us to progress to the characterization of this(ese) factor(s).