Pretransplant donor biopsy (PTDB)‐based marginal donor allocation systems to single or dual renal transplantation could increase the use of organs with Kidney Donor Profile Index (KDPI) in the ...highest range (e.g. >80 or >90), whose discard rate approximates 50% in the United States. To test this hypothesis, we retrospectively calculated the KDPI and analyzed the outcomes of 442 marginal kidney transplants (340 single transplants: 278 with a PTDB Remuzzi score <4 median KDPI: 87; interquartile range (IQR): 78–94 and 62 with a score = 4 median KDPI: 87; IQR: 76–93; 102 dual transplants median KDPI: 93; IQR: 86–96) and 248 single standard transplant controls (median KDPI: 36; IQR: 18–51). PTDB‐based allocation of marginal grafts led to a limited discard rate of 15% for kidneys with KDPI of 80–90 and of 37% for kidneys with a KDPI of 91–100. Although 1‐year estimated GFRs were significantly lower in recipients of marginal kidneys (−9.3, −17.9 and −18.8 mL/min, for dual transplants, single kidneys with PTDB score <4 and =4, respectively; p < 0.001), graft survival (median follow‐up 3.3 years) was similar between marginal and standard kidney transplants (hazard ratio: 1.20 95% confidence interval: 0.80–1.79; p = 0.38). In conclusion, PTDB‐based allocation allows the safe transplantation of kidneys with KDPI in the highest range that may otherwise be discarded.
This study shows that the standardized assessment of formalin‐fixed pretransplant biopsies helps recover donors with KDPI in the highest range that would be otherwise discarded, and by providing the expected graft outcomes based on KDPI and pretransplant biopsy, it guides the clinician facing the difficult decision whether to accept or reject these organs. See editorial by Gupta et al on page 2444.
Abstract Background Kidney transplant recipients are at higher risk of developing pulmonary complications related to immunosuppression, and inhibitor of the mammalian target of rapamycin (mTORi) has ...been reported as a potential cause. Methods Five hundred kidney-transplanted patients were retrospectively analyzed for pulmonary complications on the basis of clinical and instrumental data (chest radiography, high-resolution computed tomography, broncho-alveolar lavage, oximetry). Results We found 26 interstitial lung diseases (ILD) (16%): 12 cases (46.2%) were from infections (42.8% by Pneumocystis jirovecii ) and 14 cases of ILD (53.8%) resulted as drug-induced ILD (DI–ILD). According to anti-rejection protocols, DI–ILD occurred in 8 patients (57%) while on triple regimen including steroids, everolimus (EVL), and cyclosporine (CyA) and in 6 patients on double regimen with steroids and mTORi: EVL or sirolimus (43%). In ILD+ patients, everolimus trough-concentration (EVLTLC ) and cyclosporine (2nd-hour concentration: CyAC2 ) levels were higher than in patients in the same regimen but with ILD− (EVLTLC ng/mL 9.84 versus 6.85; CyAC2 ng/mL 303.97 versus 298.56). The formula that used the combined blood levels of both drugs (EVLTLC + CyAC2 /100) resulted in a significant difference between groups of patients (12.88 ± 1.61 versus 9.83 ± 1.91). Applying receiver operator characteristic curve (ROC) analysis to detect risk of developing ILD when on combined protocol with EVL and CyA, we obtained an area under the curve of 0.8622 ( P = .0081) and 0.9082 ( P = .0028), respectively, when using EVLTLC or the combination formula with both drugs. Conclusions In renal transplant patients, we obtained a relationship of ILD to specific drug concentration. On the basis of ROC analysis, patients on EVL and CyA combined protocol are at risk of ILD when EVLTLC is >9.03 ng/mL or >11.41 when a formula with summation of EVLTLC and CyAC2 is used.
Abstract Introduction Thrombotic microangiopathy (TMA) is characterized by endothelial cell injury and formation of fibrin thrombi within capillary and arterioles. In renal allograft recipients, TMA ...mainly presents as hemolytic uremic syndrome. Its occurrence is rare, and diagnosis requires a high degree of suspicion. Drug toxicity, in particular from calcineurin inhibitors (CNIs) and mTOR inhibitors (mTORi), is the most common cause posttransplant and has recently been emphasized in the setting of lung transplantation. Objective The goal of this study was to investigate the role of mTORi as an added risk factor in the development of TMA to propose strategies for modulation of immunosuppressive (IS) therapy. Patients and Methods From a database of 496 renal graft recipients, we analyzed 350 renal graft biopsy specimens gathered at our center from 1998 to 2012. In patients undergoing combined therapy with mTORi and CNI, we compared drugs levels in TMA-affected and TMA-free groups, using mTORi and CNI TLC and the summation of everolimus TLC + (cyclosporine C2/100) (Σ) as a surrogate marker of combined exposition to 2 drugs. Receiver-operating characteristic analysis of association of EVL TLC + (C2/100) was performed for patients exposed to mTORi. Results Histologic features of TMA were found in 36 patients (prevalence of 7.3%). The caseload was divided into 2 groups: not drug-related TMA (n = 19) and drug-related TMA (n = 17). Despite the prevalence of TMA in patients exposed to mTORi being greater (8 of 153; prevalence, 5.3%) compared with therapies without mTORi (9 of 324; prevalence, 2.8%), statistical difference was not reached. Patients treated with mTORi who developed de novo drug-related TMA had higher blood levels of IS drugs compared with those who did not develop TMA. Receiver-operating characteristic analysis found a significant threshold of 12.5 ng/mL (area under the curve, 0.803; P = .006). Conclusions Results confirm the pivotal role of IS drugs in the onset of de novo TMA. On the basis of literature, we could speculate a sequence of endothelial damage by CNI, on which everolimus fits hindering the repair of endothelial injury. Therefore, high blood levels of CNI and mTORi seem to predispose patients to posttransplant TMA. Combined monitoring of these 2 drugs might be used to prevent the complication. Σ everolimus TLC + (cyclosporine C2/100) >12.5 ng/mL should be avoided as a surrogate risk factor for adverse effects.
Abstract Background In Human immunodeficiency virus (HIV)-positive patients undergoing kidney transplantation, outcomes and immunosuppression (IS) protocol are not yet established due to infectious ...and neoplastic risks as well as to pharmacokinetic interactions with antiretroviral therapy (TARV). Methods We report a retrospective, 1-center study on 18 HIV+ patients undergoing, between October 2007 and September 2015, kidney transplantation (13 cases) or combined kidney-liver transplant (5 cases). Inclusion criteria for transplant were based on the Italian National Transplant Center protocol. IS regimen was based on quick tapering of steroids and the use of mTOR inhibitors (mTORi) with low dose of calcineurin inhibitors (CNI). In the early post-transplant period, TARV was based on enfuvirtide, raltegravir, plus 1 or more nucleoside analogues. Results In a mean follow-up of 3.1 years, patient survival rate at 1 and 3 years was, respectively, 86.6% and 84.6%, whereas graft survival was 81.2% and 78.6%. Cumulative rejection rate was 20.0% and 26.6% (1- and 3-year results). Median eGFR (MDRD) was 58.8 mL/min and 51.9 mL/min at 1 and 3 years. We had 9 cases of clinically relevant infections (2 Pneumocystis jirovecii pneumonia, 1 pulmonary aspergillosis, 2 severe sepsis, and 4 HCV reactivation) as well as 1 case (5.5%) of HIV reactivation. Conclusions IS therapy based on mTORi and low CNI dose ensures good graft survival, low rate of acute rejection, limited drug toxicity, and control of HIV disease. TARV has no significant interaction with IS therapy.
Abstract Complement factor H (CFH)-associated hemolytic uremic syndrome (HUS) is a genetic form of atypical HUS characterized by deficient CFH levels or activity, which cause a disorder of the ...regulation of the alternative pathway, leading to uncontrolled complement activation. This genetic disorder, which frequently leads to end-stage renal failure, often recurs in kidney transplants, resulting in the poorest graft outcomes among all atypical HUS forms, due to a mutation in genes encoding complement components and regulatory proteins. Herein we have report our experience with a 40-year-old woman, suffering from a clearly defined sporadic form of genetic atypical HUS, consisting of a heterozygous missense mutation in factor H gene. She underwent cadaveric kidney transplantation. At the moment of surgery she displayed positive hemolysis indices and C3 consumption. A calcineurin inhibitor (CNI)-free immunosuppressive regimen was based on sirolimus, mycophenolic acid and steroids after basiliximab induction. An early and intense prophylactic course of plasma exchange (PE), and fresh frozen plasma (40 mL/kg) was prescribed, starting before surgery and continuing daily for the first week. The frequency of PE slowly reduced over the following 2 weeks. After that, just plasma infusion at the same dose was performed once a week until 12 weeks after transplantation. There was prompt graft function and in third week there were no signs of hemolysis or of C3 consumption. More than 3 years after transplantation, the graft is still functioning well and there was no recurrence. In our opinion, this case indicates that, although evidence is lacking, avoidance of CNI and intensive prophylactic plasma therapy are essential to achieve good results in this peculiar type of kidney transplantation. Nevertheless, controlled, prospective studies are necessary to establish the actual role of these two therapeutic procedures in renal transplantation of patients with CFH-associated HUS.
Membranoproliferative GN (MPGN) was recently reclassified as alternative pathway complement-mediated C3 glomerulopathy (C3G) and immune complex-mediated membranoproliferative GN (IC-MPGN). However, ...genetic and acquired alternative pathway abnormalities are also observed in IC-MPGN. Here, we explored the presence of distinct disease entities characterized by specific pathophysiologic mechanisms. We performed unsupervised hierarchical clustering, a data-driven statistical approach, on histologic, genetic, and clinical data and data regarding serum/plasma complement parameters from 173 patients with C3G/IC-MPGN. This approach divided patients into four clusters, indicating the existence of four different pathogenetic patterns. Specifically, this analysis separated patients with fluid-phase complement activation (clusters 1-3) who had low serum C3 levels and a high prevalence of genetic and acquired alternative pathway abnormalities from patients with solid-phase complement activation (cluster 4) who had normal or mildly altered serum C3, late disease onset, and poor renal survival. In patients with fluid-phase complement activation, those in clusters 1 and 2 had massive activation of the alternative pathway, including activation of the terminal pathway, and the highest prevalence of subendothelial deposits, but those in cluster 2 had additional activation of the classic pathway and the highest prevalence of nephrotic syndrome at disease onset. Patients in cluster 3 had prevalent activation of C3 convertase and highly electron-dense intramembranous deposits. In addition, we provide a simple algorithm to assign patients with C3G/IC-MPGN to specific clusters. These distinct clusters may facilitate clarification of disease etiology, improve risk assessment for ESRD, and pave the way for personalized treatment.
Abstract Marginal donors (advanced age, comorbidities, and so on) provide an increasing contribution to the kidneys used to alleviate the relative organ shortage. We describe the evaluation process ...and clinical outcome of two kidneys with hemosiderosis used as a double graft. The donor was a 59-year-old hypertensive man, known to have a mechanical mitral valve, who died from a cerebral hemorrhage, with a normal serum creatinine (SCr) and kidneys with normal appearances at sonography. A protocol donor biopsy showed a Karpinsky score of 5 for both kidneys. A double graft was therefore scheduled. The recipient was a 59-year-old man, on dialysis because of chronic glomerulonephritis. HLA match was incompatibility 4/6; immunosuppression was based on steroids, cyclosporine, and mycophenolate mofetil with basiliximab as induction therapy. The grafts showed delayed function with dialysis treatments performed from postoperative day (POD) 1. On POD 2, a magnetic resonance imaging (MRI) study showed the typical appearance of siderosis. Pearl's staining performed on a protocol biopsy confirmed the presence of widespread iron deposits. On POD 5, a recipient renal biopsy showed a superimposed severe acute tubular necrosis. Renal function recovered slowly; SCr at discharge on POD 22 was still 4.2 mg/dL. Two months later, the SCr was 2.2 mg/dL. A second MRI performed at 3 years and 6 months after transplantation confirmed a progressive removal of iron overload while the patient had stable renal function (glomerular filtration rate) of 33 mL/min and SCr: 2.3 mg/dL. We concluded that donors with hemosiderosis should be treated as marginal donors and may be grafted based on a pretransplant biopsy.
Background. To obtain information on the management of vascular access in Italy. Method. Questionnaire sent to all dialysis centres. The main questions were: (i) who is in charge of establishing ...vascular access? (ii) How is vascular access monitored? (iii) To what extent is a continuous quality programme implemented? (iv) What proportion of patients are treated using central venous catheters at the start of dialysis? (v) What proportion of patients are treated using central venous catheters as a permanent access? (vi) What is the role of interventional radiology? Results. The response rate was 45%. All Italian regions were represented. In almost 80% of the dialysis centres vascular access is established by the nephrologist. Fistula function is monitored by most nephrologists using a recirculation test, ultrasound and radiological imaging. An audit (continuous quality programme) is implemented in 20% of the dialysis centres. A high proportion of patients are submitted for dialysis without an internal AV fistula (in one quarter of the centres more than 40% of the patients). Less than 10% of the patients are dialysed using central venous catheters as a permanent access. Interventional radiology for vascular access is used only in few centres. Comments. Because of the difficulty of coordinating different professionals, most nephrologists manage vascular access by themselves. Fistula function is usually monitored on a routine basis, but a `Continuous Quality Programme' on established standards and audit of outcome and process indicators is not followed in most centres. Late referral is a main obstacle to effective planning of renal care, as indicated by the high frequency of temporary access at the beginning of dialysis. On the whole, vascular access is properly managed by Italian nephrologists, but monitoring performance by audit would be desirable.
Abstract In Italy, referral of diabetic patients for pancreas transplantation (PT) is an unstructured process, resulting in a low rate of activity and late referrals, often when the patient has ...already undergone dialysis. In addition, the continuous improvement in pancreas transplant alone, offering the opportunity to reduce cardiovascular risk due to proteinuria and reduced glomerular filtration rate (GFR), is rarely appreciated. We therefore analyzed (1) referral activity to PT during the time frame 2001–2005 in Emilia-Romagna, Italy (four million inhabitants), by collecting ICD 9 CM codes (55.69 + 52.80; 52.86 and 52.80 alone) by residence of the patient; (2) demand for PT among a sample population of 1670 diabetes patients, whose charts were reviewed for the type of diabetes and presence of overt diabetic nephropathy (DN: proteinuria > 300 mg/24 h and/or GFR < 60 mL/min); (3) potential pancreas availability as the ratio between pancreas and hearts utilized (UP/HR) in different areas of our country. As a results, (1) referral activity reached 8.4 PT per million people in 5 years in the whole region, ranging from 2.6 in the province where a PT program is active, to a maximum value of 20.7 in the province where a devoted outpatient clinic is operated by nephrologists. (2) Prevalence of overt DN was 6% in our cohort, corresponding to 510 D1 patients worthy of evaluation for PT inside Emilia-Romagna region. (3) During 2006, UP/HR was 0.58 in Associazione Inter-Regionale Trapianti agency, 1.16 in Tuscany, 0.30 in Piedmont, and 0.26 in our region. Taken together, our data showed that (1) the referral of D1 to PT has to be empowered, keeping in touch with all patients suffering from diabetic nephropathy; (2) the outpatient clinic devoted to evaluation and recruitment of D1 with nephropathy plays the key role in this program of timely and widespread referral; (3) the availability of pancreata can be increased by utilizing broader criteria for harvesting, increased consent rate to donation and increased the demand for PT (recipient pool). Pancreas grafts need to increase, since the current low demand produces underutilization of the pancreas resource, due to the frequent lack of a suitable recipient.
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