Isolated v‐lesion in kidney transplant recipients: Characteristics, association with DSA,and histological follow‐up

Isolated v‐lesion (IvL) represents a rare and challenging situation in renal allograft biopsies because it is unknown whether IvL truly represents rejection, antibody‐ or T cell–mediated, or not. This multicentric retrospective study describes the clinicopathological features of IvL with an emphasis on the donor‐specific antibody (DSA) status, histological follow‐up, and graft survival. Inclusion criteria were the presence of v‐lesion with minimal interstitial (i ≤ 1) and microvascular inflammation (g + ptc≤1). C4d‐positive biopsies were excluded. We retrospectively found 33 IvL biopsies in 33 patients, mainly performed in the early posttransplantation period (median time 27 days) and clinically indicated in 66.7%. A minority of recipients (5/33, 15.2%) had DSAat the time of biopsy. IvL was treated by anti‐rejection therapy in 21 cases (63.6%), whereas 12 (36.4%) were untreated. Seventy percent of untreated patients and 66% of treated patients showed favorable histological evolution on subsequent biopsy. Kidney graft survival in IvL was significantly higher than in a matched cohort of antibody‐mediated rejection with arteritis. In conclusion, IvL is not primarily antibody‐mediated and may show a favorable evolution. The heterogeneity of IvL pathophysiology on early biopsies should prompt DSAtesting as well as close clinical and histological follow‐up in all patients with IvL. The authors show that isolated v‐lesion in kidney allograft recipients is mainly found in the early posttransplant period in a majority of donor‐specific antibody–negative patients, and is associated with good graft survival.