Guillaume Canaud

Introduction. Recurrence of nephrotic-range proteinuria in patients with idiopathic nephrotic syndrome (INS) and focal and segmental glomerulosclerosis (FSGS) on native kidneys is associated with poor graft survival. Identification of risk factors for recurrence is therefore an important issue. In 2004, Columbia University introduced a histological classification of FSGS that identifies five mutually exclusive variants. In non-transplant patients, the Columbia classification appears to predict the outcome and response to treatment better than clinical characteristics alone. However, the predictive value of this classification to assess the risk of recurrence after transplantation has not been addressed. We retrospectively studied 77 patients with INS and FSGS on native kidneys who underwent renal transplantation. Of these, 42 recipients experienced recurrence of nephrotic range proteinuria. At time of recurrence, minimal-change disease (MCD) was the main histological feature. On serial biopsies, the incidence of MCD decreased over time, while the incidence of FSGS variants increased. The variant type observed in the native kidneys was not predictive of either recurrence or type of FSGS seen on the allograft. Patients with complete and sustained remission did not developed FSGS. In conclusion, the Columbia classification is of no help in predicting recurrence after renal transplantation or histological lesions in the case of recurrence of proteinuria.

Fungal contamination of kidney allograft preservative fluid can lead to renal arteritis and arterial wall rupture. We have evaluated a conservative management strategy based onearly antifungal therapy, rigorous morphological monitoring of the graft artery and surgical second look (SSL). Since November 2004, preservative fluid was routinely cultured on specific media for all kidney transplant recipients. In 8/474 cases, results were positive for Candida (albicans 5, glabrata 2, tropicalis 1). Two patients also had candida infection of drainage fluid leading to the diagnosis of operative site infection. Radiological and surgical examinations of the renal graft artery were normal in all cases and nephrectomy was not required. At 12 months, all patients were alive with a functioning allograft. Early antifungal therapy with microbiological and morphological follow-up should be recommended as soon as contamination is detected, but SSL is advised only in patients with risk factors for arterial anomalies.