De Novo Posttransplant Thrombotic Microangiopathy Localized Only to the Graft in APKD with Thrombophilia

Background: Thrombotic microangiopathy (TMA) is a serious complication of renal transplantation (Tx) and is mostly related to the prothrombotic effect of calcineurin inhibitors (CNIs). A subset of TMA (29-38%) is localized only to the graft. Case 1: A young woman suffering from adult polycistyc kidney disease (APKD) underwent kidney transplant. After 2 months, she showed slow renal deterioration (Scr from 1.9 to 3.1 mg/dl), without hematological signs (anaemia, low platelets, low serum haptoglobins, schistocytosis >1%) of haemolytic-uremic syndrome (HUS); only lactate dehydrogenase enzyme (LDH) transient increase was detected. Renal biopsy showed TMA: temporary withdraw of tacrolimus and plasmapheresis was performed. The renal function recovered and stabilized (Scr 1.9 mg/dL). From Screening for thrombophilia, we found a mutation of the Leiden Factor V gene. Case 2: An old man affected by APKD underwent Tx, with delayed graft function (DGF); first biopsy showed acute tubular necrosis, but a second biopsy on day 45 revealed TMA; no altered hematological parameters of HUS was detected. Again, we observed only a light increase of LDH levels. The tacrolimus was halved and plasmapheresis was performed: LDH levels normalized within 10 days and renal function improved (Scr from 9 to 2.9 mg/dl). In this patient, we found a mutation of the Prothrombin gene. Only a renal biopsy clarifies the diagnosis of TMA localized into the graft, but it is necessary to pay attention to light increasing level of LDH. Conclusions: Prothrombotic effect of CNIs and M-Thor inhibitor, mutation of genes encoding factor H or I, anticardiolipin antibodies, vascular rejection, cytomegalovirus or parvovirus B19 infection are proposed to trigger TMA; we detected mutations of Factor II and Leiden Factor V, as facilitating conditions for TMA in patients affected by APKD. Citation: Rolla D, Fontana I,Ravetti JL, Marsano L, Bellino D, et al. (2015) De Novo Posttransplant Thrombotic Microangiopathy Localized Only to the Graft in APKD with Thrombophilia. J Kidney 1: 101. doi:10.4172/2472-1220.1000101