A single‐staggered dose of calcineurin inhibitor may be associated with neurotoxicity and nephrotoxicity immediately after liver transplantation

Abstract: The aim of the present work was to assess the incidence of neuro‐nephrotoxicity after a single‐staggered dose of calcineurin inhibitors (CI) with different immunosuppressive approaches. From January to December 2006, all liver transplantation (LT) recipients at risk of renal or neurological complications treated with extracorporeal photopheresis (ECP) + mycophenolate mofetil + steroids and staggered introduction of CI (ECP group) were compared with a historical control group on standard CI‐based immunosuppression. The ECP group included 24 patients with a mean model for end‐stage liver disease (MELD) score of 19.9 ± 11.1. The control group consisted of 18 patients with a mean MELD score of 12.5 ± 5.2 (p = 0.012). In the ECP group CI were introduced at a mean of 9.2 ± 6.2 d (4–31 d) after LT. Five patients in the ECP group presented acute neuro‐nephrotoxicity after the first CI administration on post‐transplant d 4, 5, 6, 6, and 14. Overall patient survival at one, six, and 12 months was 100%, 95.8%, and 95.8% in the ECP group vs. 94.4%, 77.7%, and 72.2% in the control group (p < 0.001). In conclusion, we showed that CI toxicity may occur after a single‐staggered dose administration, ECP seems to be a valuable tool for managing CI‐related morbidity regardless of the concomitant immunosuppressive regimen, being associated with a lower mortality rate in the early post‐transplant course.     

Everolimus with early withdrawal or reduced‐dose calcineurin inhibitors improves renal function in liver transplant recipients: A systematic review and meta‐analysis

Calcineurin inhibitors (CNI) are the mainstay of immunosuppression after liver transplantation (LT), but CNIs are associated with significant nephrotoxicity. Recently, mTOR inhibitors such as sirolimus and everolimus (EVR) have been used with or without CNIs in LT recipients for their renal‐sparing effect. We conducted a systematic review and meta‐analysis of randomized controlled trials (RCT) that examined the effect of EVR with CNI minimization or withdrawal on renal function in LT recipients. RCT of primary adult LT recipients with baseline GFR >30 mL/min who received EVR with CNI minimization or withdrawal were included. Four RCTs (EVR n=465, control n=428) were included. In three RCTs, EVR was initiated 4 weeks following LT; these studies were used to assess the primary outcome. All four studies were used to assess the secondary outcomes. Based on this study, EVR use with CNI minimization in LT recipients is associated with improved renal function at 12 months by GFR of 10.2 mL/min (95% CI: 2.75‐17.8). EVR use was not associated with an increased risk of biopsy‐proven acute rejection (RR 0.68, 95% CI: 0.31‐1.46), graft loss (RR 1.60, 95% CI: 0.51‐5.00), or mortality (RR 1.34, 95% CI 0.62‐2.90). However, it was associated with an increased risk of overall infections (RR 1.45, 95% CI: 1.10‐1.91).     

Postural hand tremor before and following liver transplantation and immunosuppression with cyclosporine or tacrolimus in patients without clinical signs of hepatic encephalopathy

OBJECTIVE: To assess tremor characteristics and severity in patients with severe liver disease without hepatic encephalopathy and following orthotopic liver transplantation (LTX) and immunosuppression (IS) with cyclosporin A (CsA) or tacrolimus (FK 506). METHODS: A total of 35 consecutive patients were included into the prospective study and serum levels of CsA (n = 29) or FK 506 (n = 6) were monitored following LTX. Tremor characteristics and severity were assessed by two-blinded raters before and following LTX. In addition, accelerometric recordings were taken before and after LTX, and compared with 16 normal controls without tremor and without clinical signs of hepatic encephalopathy or liver disease. Accelerometry was performed while sitting in a comfortable chair with the forearms supported and included rest and postural condition with and without weight load (500 g) on each hand. Kolmogorov-Smirnov test, paired t-test and t-test for independent samples were used for statistical analysis. RESULTS: The clinical rating revealed no rest but a mild postural hand tremor before LTX with a significant increase following LTX (p < 0.001). After LTX the mean score of postural tremor was significantly (p < 0.05) higher in patients with plasma levels of >850 ng CsA/ml compared with patients with lower levels. Patients and normal controls showed comparable mean peak frequencies of rest and postural hand tremor. The mean amplitude of postural hand tremor was significantly higher in patients before and after LTX compared with controls. In the majority of patients (89%) and controls (88%), the dominant tremor frequency decreased significantly (>1.5 Hz) when applying a weight load on each hand. CONCLUSION: The present study is the first to describe hand tremor characteristics in patients with severe liver disease without clinical signs of hepatic encephalopathy and in patients following LTX and IS. Compared with normal controls the patients showed a significant postural hand tremor prior and post-LTX and an increase of mean tremor amplitude following LTX and CsA/FK 506 treatment. The decrease of the dominant tremor frequency with weight load and an increase of tremor amplitude with higher plasma levels of CsA are both indicative of an enhanced physiological or toxic tremor.     

Incidence,etiology, and significance of acute kidney injury in the early post‐kidney transplant period

Little is known about the incidence, causes, and significance of acute kidney injury (AKI) in the early transplant period. This study used a definition as >26 μmol/L increase in creatinine within 48 h or >50% increase over a period >48 h. In 326 adult consecutive recipients of a solitary kidney transplant from 2006 to 2014 followed at this center, 21% developed AKI within the first six months. Most etiologies were CNI toxicity (33%) or unknown (26%), whereas acute rejection accounted for 17% and urinary tract obstruction for 10%. Those with AKI had a significantly lower glomerular filtration rate (GFR) at one‐yr post‐transplant (adjusted beta coefficient ?5.5 mL/min/1.73 m², 95% CI: ?10.4, ?0.7, p = 0.025) in a multivariable linear regression model. However, the AKI definition missed 6 of 19 episodes of acute rejection and 4 of 10 episodes of urinary tract obstruction. When acute rejection (including those that did not satisfy AKI criteria) was included in the model, other causes of AKI were not significantly associated with GFR at year 1. Although AKI, using current criteria, is likely to be a significant predictor of later outcomes, important causes are missed and the criteria are not sensitive for clinical decision‐making.     

Influence of CYP3A5 and ABCB1 gene polymorphisms on calcineurin inhibitor‐related neurotoxicity after hematopoietic stem cell transplantation

Yanagimachi M, Naruto T, Tanoshima R, Kato H, Yokosuka T, Kajiwara R, Fujii H, Tanaka F, Goto H, Yagihashi T, Kosaki K, Yokota S. Influence of CYP3A5 and ABCB1 gene polymorphisms on calcineurin inhibitor‐related neurotoxicity after hematopoietic stem cell transplantation.
Clin Transplant 2010: 24: 855–861. © 2009 John Wiley & Sons A/S. Abstract: Background: One severe side effect of calcineurin inhibitors (CNIs: such as cyclosporine [CsA] and tacrolimus [FK506]) is neurotoxicity. CNIs are substrates for CYP3A5 and P‐glycoprotein (P‐gp), encoded by ABCB1 gene. In the present study, we hypothesized that genetic variability in CYP3A5 and ABCB1 genes may be associated with CNI‐related neurotoxicity. Methods: The effects of the polymorphisms, such as CYP3A5 A6986G, ABCB1 C1236T, G2677T/A, and C3435T, associated with CNI‐related neurotoxicity were evaluated in 63 patients with hematopoietic stem cell transplantation. Results: Of the 63 cases, 15 cases developed CNI‐related neurotoxicity. In the CsA patient group (n = 30), age (p = 0.008), hypertension (p = 0.017), renal dysfunction (p < 0.001), ABCB1 C1236T (p < 0.001), and G2677T/A (p = 0.014) were associated with neurotoxicities. The CC genotype at ABCB1 C1236T was associated with it, but not significantly so (p = 0.07), adjusted for age, hypertension, and renal dysfunction. In the FK506 patient group (n = 33), CYP3A5 A6986G (p < 0.001), and ABCB1 C1236T (p = 0.002) were associated with neurotoxicity. At least one A allele at CYP3A5 A6986G (expressor genotype) was strongly associated with it according to logistic regression analysis (p = 0.01; OR, 8.5; 95% CI, 1.4–51.4). Conclusion: The polymorphisms in CYP3A5 and ABCB1 genes were associated with CNI‐related neurotoxicity. This outcome is probably because of CYP3A5 or P‐gp functions or metabolites of CNIs.     

Amlodipine and calcineurin inhibitor‐induced nephrotoxicity following allogeneic hematopoietic stem cell transplant

Studies in the renal transplant population have suggested calcium‐channel blockers (CCBs) may protect against calcineurin inhibitor (CNI)‐induced nephrotoxicity. However, this has not been evaluated in the hematopoietic stem cell transplant (HSCT) population. This retrospective study reviews data from 350 consecutive patients who underwent allogeneic HSCT to determine whether amlodipine improved renal outcomes. Subject data included up to one year from CNI initiation. Patients in the amlodipine group (n = 130) received an average of 143 days treatment with amlodipine and experienced a smaller decrease in creatinine clearance (CrCl) through day 180. At day 30, change in CrCl was ?17.4 mL/min in the amlodipine cohort and ?33.8 mL/min in the control (P < 0.001). At day 180, change in CrCl was ?40.9 and ?50.6 mL/min, respectively (P = 0.005). Incidence of hospitalization with acute kidney injury (AKI) was significantly lower in patients receiving amlodipine, 7.7% (10/132) vs 16.4% (36/220) (hazard ratio [HR] 0.44; 95% confidence interval [CI] 0.22‐0.89). Median blood pressure in the amlodipine group remained <132/78 through day 360. Our data support the use of amlodipine for hypertension in the allogeneic HSCT population and provide evidence suggesting that CCBs protect against CNI‐induced nephrotoxicity.     

Two yr mycophenolate mofetil plus low-dose calcineurin inhibitor for renal dysfunction after liver transplant

Abstract:  We assessed the efficacy and outcome of low through level of calcineurin inhibitors (CNI) and introducing mycophenolate mofetil (MMF) in liver transplant (LT) patients with CNI-related renal dysfunction. Thirty LT patients were converted to combined therapy and compared with 30 patients used as a contemporary control group receiving CNI only. The two groups were matched for sex, age, months after LT, immunosuppressive treatment, creatinine level, presence of diabetes and calculated glomerular filtration rate (GFR) via Cockroft-Gault method. After two years, in the MMF serum creatinine decreased from 1.65 mg/dL (range 1.33–3.5) to 1.4 mg/dL (range 0.9–4.7) (p = 0.002) and GFR increased from 51 mL/min (range 18.9–72.2) to 57.6 mL/min (range 16–92.2) (p < 0.001), whereas the controls not showed any improvement. The logistic regression models employing improvement of creatinine and GFR of at least 10% with respect to baseline as dependent variables showed the use of MMF (p = 0.004 and p = 0.019, respectively) as the only statistically significant parameter. Multiple linear regression analysis identified only MMF as independent predictor of Δcreatinine and ΔGFR (p = 0.002 and p < 0.001, respectively). No rejection episode was observed (three in controls). This study demonstrates the medium-term efficacy and safety of MMF plus low dose CNI in reducing nephrotoxicity in LT recipients.     

Once‐daily,prolonged‐release tacrolimus vs twice‐daily,immediate‐release tacrolimus in de novo living‐donor liver transplantation: A Phase 4, randomized,open‐label,comparative, single‐center study

Randomized, open‐label, comparative, single‐center, Phase 4, 24‐week study comparing pharmacokinetics (PK), safety, and efficacy of once‐daily, prolonged‐release tacrolimus (PR‐T) with twice‐daily, immediate‐release tacrolimus (IR‐T) in adult de novo living‐donor liver transplant (LDLT) recipients in Korea. All patients received intravenous tacrolimus from Day 0 (transplantation) for 4 days and were randomized (1:1) to receive oral PR‐T or IR‐T from Day 5. PK profiles were taken on Days 6 and 21. Primary endpoint: area under the concentration‐time curve over 24 hour (AUC_0‐24). Predefined similarity interval for confidence intervals of ratios: 80%‐125%. Secondary endpoints included: tacrolimus concentration at 24 hour (C₂₄), patient/graft survival, biopsy‐confirmed acute rejection (BCAR), treatment‐emergent adverse events (TEAEs). One‐hundred patients were included (PR‐T, n = 50; IR‐T, n = 50). Compared with IR‐T, 40% and 66% higher mean PR‐T daily doses resulted in similar AUC_0‐24 between formulations on Day 6 (PR‐T:IR‐T ratio of means 96.8%), and numerically higher AUC_0‐24 with PR‐T on Day 21 (128.8%), respectively. Linear relationship was similar between AUC_0‐24 and C₂₄, and formulations. No graft loss/deaths, incidence of BCAR and TEAEs similar between formulations. Higher PR‐T vs IR‐T doses were required to achieve comparable systemic exposure in Korean de novo LDLT recipients. PR‐T was efficacious; no new safety signals were detected.     

Selective treatment of early acute rejection after liver transplantation: Effects on liver,infection rate,and outcome

To evaluate the results of selective treatment of biopsy-proven mild acute rejection episodes, we retrospectively studied 1-week liver biopsies of 103 patients with a primary liver graft in relation to liver function tests. The overall incidence of rejection was 35 %. In four patients the biopsy showed histological features consistent with rejection; in 27 patients it showed mild acute rejection (grade 1), and in 5 patients it showed moderate acute rejection (grade 2). Study group 1 consisted of 19 untreated patients with grade 1 rejection and group 2 of 8 treated patients with grade 1 rejection. At 30 and 90 days, no differences in liver function tests were found. The infection rate, histology after 1 year, and survival in the two groups did not differ. It may, therefore, be concluded that withholding treatment in histologically proven mild acute rejection is possible in selected patients based on histological, biochemical, and clinical criteria. This may reflect the functional diversity of morphologically similar lymphocytic infiltrates observed in graft biopsies showing features of mild acute rejection.Liver Transplant Group     

Selective treatment of early acute rejection after liver transplantation: effects on liver, infection rate, and outcome

Abstract To evaluate the results of selective treatment of biopsy-proven mild acute rejection episodes, we retrospectively studied 1-week liver biopsies of 103 patients with a primary liver graft in relation to liver function tests. The overall incidence of rejection was 35 %. In four patients the biopsy showed histological features consistent with rejection; in 27 patients it showed mild acute rejection (grade 1), and in 5 patients it showed moderate acute rejection (grade 2). Study group 1 consisted of 19 untreated patients with grade 1 rejection and group 2 of 8 treated patients with grade 1 rejection. At 30 and 90 days, no differences in liver function tests were found. The infection rate, histology after 1 year, and survival in the two groups did not differ. It may, therefore, be concluded that withholding treatment in histologically proven mild acute rejection is possible in selected patients based on histological, biochemical, and clinical criteria. This may reflect the functional diversity of morphologically similar lymphocytic infiltrates observed in graft biopsies showing features of mild acute rejection.     

Causes of early acute graft failure after liver transplantation: analysis of a 17-year single-centre experience

Despite satisfactory overall results reported, early post-operative period after liver transplantation (LT) still represents a critical time with persistently high rate of graft loss. We retrospectively reviewed our experience of 17 yr in LT, analysing the impact on grafts and patient survivals of the acute complications affecting the graft in the early period following LT. To evaluate the changes that occurred over the years in case of early acute graft failure (EAGF), the study population was divided into three equal groups of 223 patients corresponding to three different periods. Ninety (13.5%) experienced an EAGF. Causes of EAGF were hepatic artery thrombosis (HAT) in 32 cases (4.8%), primary graft non-function in 29 cases (4.3%), caval stenosis in 19 (2.8%), early irreversible acute rejection in 6 (0.9%) and portal vein thrombosis in 4 (0.6%). The use of elderly donors and the introduction of the piggyback technique proved to be associated with a higher incidence of HAT and caval stenosis, respectively. Female recipients of male donors were independently associated with Primary graft non-function. Of 90 patients with EAGF, 20 (22.2%) died within the first month after LT, 34 (37.8%) underwent retransplantation (ReLT) and 36 (40%) received conservative treatment. Conservative treatments increased from 3.6% in the first group to 47.0 and 66.8% in the second and third one (p = 0.000). One-year graft and patient survival of patients with EAGF significantly improved over the three eras analysed. The incidence of EAGF remains consistent. Nevertheless, a better understanding of the clinical situations and changes in treatment strategies have led to significant improvements in terms of graft and patient survival rates, now close to the survival rate of EAGF-free patients.     

Relationship between renal resistance index and renal function in liver transplant recipients after cessation of calcineurin inhibitor

Abstract:  End stage renal disease is a major complication after orthotopic liver transplantation (OLT). Vasoconstriction of renal arterial vessels because of calcineurin inhibitor (CNI) treatment plays a pivotal role in the development of renal insufficiency following OLT. Renal resistance can be measured non-invasively by determining the resistance index (RI) of segmental arteries by color-coded duplex ultrasonography, a measure with predictive value for future renal failure. Sixteen OLT patients on long-term CNI therapy were recruited prospectively and randomly assigned either to receive the m-TOR inhibitor sirolimus (SRL) or to continue on CNI treatment, and were followed for one yr. Serum creatinine (crea) declined after conversion to SRL, whereas it tended to increase in patients remaining on CNI (meanΔ crea SRL: −27, −18, −18, −15 μmol/L; meanΔ crea CNI: 4, 5, 8, 11 μmol/L at 1, 3, 6, 12 months, p = 0.02). RI improved after switching to SRL and was lower on SRL than on CNI (meanΔRI SRL: −0.04, −0.04, −0.03, −0.03; meanΔRI CNI: −0.006, 0.004, −0.007, −0.01 after 1, 3, 6, 12 months, p = 0.016). Individual changes of RI correlated significantly with individual changes of crea ( r  = 0.54, p < 0.001). Conversion from CNI to SRL can ameliorate renal function accompanied by a reduction of intrarenal RI after OLT.     

An objective definition for clinical suspicion of T‐cell‐mediated rejection after liver transplantation

A uniform definition of clinical suspicion of T‐cell‐mediated rejection (TCMR) in liver transplantation (LT) is needed to homogenize clinical decisions, especially within randomized trials. This multicenter study included a total of 470 primary LT recipients. The derivation cohort consisted of 142 patients who had clinically driven liver biopsies at any time after LT. The external validation cohort included 328 patients who underwent protocol biopsies at day 7‐10 after LT. The rates of moderate‐severe histological TCMR were 33.8% in the derivation cohort and 43.6% in the validation cohort. Independent predictors (ie, risk factors) of moderate‐severe TCMR in the derivation cohort were as follows: serum bilirubin >4 mg/dL (OR=5.83; P<.001), rising bilirubin within the 4 days prior to liver biopsy (OR=4.57; P=.003), and blood eosinophils count >0.1×10⁹/L (OR=3.81; P=.004). In the validation cohort, the number of risk factors was an independent predictor of moderate‐severe TCMR (OR=1.74; P=.001), after controlling for hepatitis C status. The number of risk factors paralleled the rates of moderate‐severe TCMR in the derivation and validation cohorts (P<.001 in both comparisons). In conclusion, increased serum bilirubin, rising bilirubin and eosinophilia are validated risk factors for moderate‐severe histological TCMR and could be used as objective criteria to select candidates for liver biopsy.