Everolimus, Cyclosporine, and Thrombotic Microangiopathy: Clinical Role and Preventive Tools in Renal Transplantation

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

Kidney Transplantation in HIV-Infected Recipients: Therapeutic Strategy and Outcomes in Monocentric Experience

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

Interstitial Lung Disease after Kidney Transplantation and the Role of Everolimus

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

The Overweight Paradox: Impact of Body Mass Index on Patients Undergoing VATS Lobectomy or Segmentectomy

The aim of this study was to assess the impact of BMI on perioperative outcomes in patients undergoing VATS lobectomy or segmentectomy. Data from 5088 patients undergoing VATS lobectomy or segmentectomy, included in the VATS Group Italian Registry, were collected. BMI (kg/m2) was categorized according to the WHO classes: underweight, normal, overweight, obese. The effects of BMI on outcomes (complications, 30-days mortality, DFS and OS) were evaluated with a linear regression model, and with a logistic regression model for binary endpoints. In overweight and obese patients, operative time increased with BMI value. Operating room time increased by 5.54 minutes (S.E. = 1.57) in overweight patients, and 33.12 minutes (S.E. = 10.26) in obese patients (P < 0.001). Compared to the other BMI classes, overweight patients were at the lowest risk of pulmonary, acute cardiac, surgical, major, and overall postoperative complications. In the overweight range, a BMI increase from 25 to 29.9 did not significantly affect the length of stay, nor the risk of any complications, except for renal complications (OR: 1.55; 95% CI: 1.07-2.24; P = 0.03), and it reduced the risk of prolonged air leak (OR: 0.8; 95% CI: 0.71-0.90; P < 0.001). 30-days mortality is higher in the underweight group compared to the others. We did not find any significant difference in DFS and OS. According to our results, obesity increases operating room time for VATS major lung resection. Overweight patients are at the lowest risk of pulmonary, acute cardiac, surgical, major, and overall postoperative complications following VATS resections. The risk of most postoperative complications progressively increases as the BMI deviates from the point at the lowest risk, towards both extremes of BMI values. Thirty days mortality is higher in the underweight group, with no differences in DFS and OS