The Burden of Chronic Kidney Disease in Long-Term Liver Transplant Recipients

Newly developed sarcopenia after liver transplantation, determined by a fully automated 3D muscle volume estimation on abdominal CT, can predict post-transplant diabetes mellitus and poor survival outcomes

BACKGROUND

Loss of muscle mass is the most common complication of end-stage liver disease and negatively affects outcomes for liver transplantation (LT) recipients. We aimed to determine the prognostic value of a fully automated three-dimensional (3D) muscle volume estimation using deep learning algorithms on abdominal CT in patients who underwent liver transplantation (LT).

METHODS

This retrospective study included 107 patients who underwent LT from 2014 to 2015. Serial CT scans, including pre-LT and 1- and 2-year follow-ups were performed. From the CT scans, deep learning-based automated body composition segmentation software was used to calculate muscle volumes in 3D. Sarcopenia was calculated by dividing average skeletal muscle area by height squared. Newly developed-(ND) sarcopenia was defined as the onset of sarcopenia 1 or 2 years after LT in patients without a history of sarcopenia before LT. Patients' clinical characteristics, including post-transplant diabetes mellitus (PTDM) and Model for end-stage liver disease score, were compared according to the presence or absence of sarcopenia after LT. A subgroup analysis was performed in the post-LT sarcopenic group. The Kaplan-Meier method was used for overall survival (OS).

RESULTS

Patients with ND-sarcopenia had poorer OS than those who did not (P = 0.04, hazard ratio [HR], 3.34; 95% confidence interval [CI] 1.05 - 10.7). In the subgroup analysis for post-LT sarcopenia (n = 94), 34 patients (36.2%) had ND-sarcopenia. Patients with ND-sarcopenia had significantly worse OS (P = 0.002, HR 7.12; 95% CI 2.00 - 25.32) and higher PTDM occurrence rates (P = 0.02, HR 4.93; 95% CI 1.18 - 20.54) than those with sarcopenia prior to LT.

CONCLUSION

ND-sarcopenia determined by muscle volume on abdominal CT can predict poor survival outcomes and the occurrence of PTDM for LT recipients.

Impact of Abdominal Aortic Calcification on Chronic Kidney Disease After Liver Transplantation: A Retrospective Study

BACKGROUND

With improved graft and patient survival after liver transplantation (LT), the onset of late complications, such as renal dysfunction, has become a problem. In this study, we aimed to investigate abdominal aortic calcification (AAC), a potential indicator of systemic atherosclerosis, and evaluate the relationship between preoperative AAC and postoperative chronic kidney disease (CKD), as the latter might be a long-term complication after LT.

METHODS

Among the 184 LTs performed at our center between 2008 and 2021, 110 LTs with normal renal function (estimated glomerular filtration rate [eGFR] 60 mL/min per 1.73 m²) before surgery were included. These were divided into high- (≥100 mm³) and low-AAC groups (<100 mm³) consisting of 51 and 59 patients, respectively. The AAC volume was automatically calculated for calcifications located in the abdominal aorta using the Agatston method.

RESULTS

The high-AAC group was older, consisted of more men, and had lower preoperative creatinine and eGFR levels. No significant difference in the onset of postoperative CKD was found between the 2 groups. However, the cumulative incidence of postoperative CKD was significantly higher in the high-AAC group compared with the low-AAC group. Multivariate analysis of postoperative CKD using the Cox proportional hazards model showed significant differences in preoperative AAC ≥100 mm³, recipient age ≥50 years, and preoperative eGFR <75 mL/min per 1.73 m².

CONCLUSIONS

The development of postoperative CKD should be monitored in liver transplant recipients despite normal preoperative renal function. Our study suggests that preoperative AAC may influence postoperative renal dysfunction.

[Kidney failure after liver transplantation]

One third of cirrhotic patients present impaired kidney function. It has multifactorial causes and has a harmful effect on patients' morbi-mortality before and after liver transplant. Kidney function does not improve in all patients after liver transplantation and liver-transplant recipients are at high risk of developing chronic kidney disease. Causes for renal dysfunction can be divided in three groups: preoperative, peroperative and postoperative factors. To date, there is no consensus for the modality of evaluation the risk for chronic kidney disease after liver transplantation, and for its prevention. In the present review, we describe the outcome of kidney function after liver transplantation, and the prognostic factors of chronic kidney disease to determine a risk stratification for each patient. Furthermore, we discuss therapeutic options to prevent kidney dysfunction in this setting, and highlight the indications of combined liver-kidney transplantation.

Chronic Kidney Disease Following Liver Transplant: Associated Outcomes and Predictors

OBJECTIVES

Liver transplant as a life-saving procedure in patients with end-stage liver disease may have some complications such as renal dysfunction. Improved postoperative management and immuno- suppressive therapy have increased long-term survival and thus increased late complications like chronic kidney disease. Our study aimed to investigate outcomes of chronic kidney disease in liver transplant recipients and the incidence, progression rates, and adjustable risk factors of chronic kidney disease after liver transplant.

MATERIALS AND METHODS

Related studies published in English were elicited from various international sources like the ISI Web of Science, PubMed/Medline, Google Scholar, and Scopus.

RESULTS AND CONCLUSIONS

Chronic kidney disease as a long-term complication is common in liver transplant recipients whose survival is affected by renal function. Risk assessment of renal function before liver transplant and some nonrenal causes of chronic kidney disease after transplant could help reduce the risks associated with future renal outcomes.

Acute kidney injury and chronic kidney disease after liver transplant: A retrospective observational study

BACKGROUND AND RATIONALE

Chronic kidney disease remains an important risk factor for morbidity and mortality among LT recipients, but its exact incidence and risk factors are still unclear.

MATERIAL AND METHODS

We carried out a retrospective cohort study of consecutive adults who underwent liver transplant (January 2009-December 2018) and were followed (at least 6 months) at our institution. CKD was defined following the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 Clinical Practice Guidelines. Long-term kidney function was classified into 4 groups: no CKD (eGFR, ≥60mL/min/1.73m²), mild CKD (eGFR, 30-59mL/min/1.73m²), severe CKD (eGFR, 15-29mL/min/1.73m²), and end-stage renal disease (ESRD).

RESULTS

We enrolled 410 patients followed for 53.2±32.6 months. 39 had CKD at baseline, and 95 developed de novo CKD over the observation period. There were 184 (44.9%) anti-HCV positive, 47 (11.5%) HBsAg positive, and 33 (8.1%) HBV/HDV positive recipients. Recipient risk factors for baseline CKD were advanced age (P=0.044), raised levels of serum uric acid (P<0.0001), and insulin dependent DM (P=0.0034). Early post-transplant AKI was common (n=95); logistic regression analysis found that baseline serum creatinine was an independent predictor of early post-LT AKI (P=0.0154). According to our Cox proportional hazards model, recipient risk factors for de novo CKD included aging (P<0.0001), early post-transplant AKI (P=0.007), and baseline serum creatinine (P=0.0002). At the end of follow-up, there were 116 LT recipients with CKD - 109 (93.9%) and 7 (6.1%) had stage 3 and advanced CKD, respectively. Only two of them are undergoing long-term dialysis.

CONCLUSION

The incidence of CKD was high in our cohort of LT recipients, but only a slight decline in kidney function over time was recorded. Prevention of post-transplant AKI will improve kidney function in the long run. We need more studies to analyze the function of kidneys among LT recipients over extended follow-ups and their impact on mortality.

A meta-analysis of the cumulative incidence, risk factors, and clinical outcomes associated with chronic kidney disease after liver transplantation

Chronic kidney disease (CKD) remains a relatively common complication after liver transplantation (LT), and significantly impacts overall survival. We sought to assess the cumulative incidence, risk factors and mortality associated with post-LT CKD. CKD was defined as eGFR <60 ml/min/1.73 m² as estimated by the Modified Diet in Renal Disease (MDRD) formula. Single-arm meta-analysis was done to evaluate the cumulative incidence of CKD at 1-, 3-, and 5-year timepoints post-LT. Risk factors for CKD were evaluated using hazard ratios (HR). Twenty-one studies involving 44 383 patients were included. Cumulative incidence of stage 3-5 CKD was 31.44% (CI 0.182-0.447), 36.71% (CI 0.188-0.546), and 43.52% (CI 0.296-0.574) at 1, 3, and 5 years after LT, respectively. Stage 5 CKD cumulative incidence increased from 0.274% (CI 0.001-0.005) at 1 year to 2.06% (CI 0.009-0.045) at 5 years post-LT. Age, female sex, diabetes, and peri-operative acute kidney injury (AKI) were significant risk factors for CKD. Stage 4-5 CKD was associated with a decrease in overall survival (HR 3.23, 95% CI 1.74-5.98, P < 0.01). CKD after LT is relatively common, and is associated with significantly reduced overall survival. Identification of patients at high risk of developing CKD allows physicians to prophylactically use renal-sparing immunosuppression which may be crucial in achieving desirable clinical outcomes.

Kidney Failure after Liver Transplantation

One-third of patients with cirrhosis present kidney failure (AKI and CKD). It has multifactorial causes and a harmful effect on morbidity and mortality before and after liver transplantation. Kidney function does not improve in all patients after liver transplantation, and liver transplant recipients are at a high risk of developing chronic kidney disease. The causes of renal dysfunction can be divided into three groups: pre-operative, perioperative and post-operative factors. To date, there is no consensus on the modality to evaluate the risk of chronic kidney disease after liver transplantation, or for its prevention. In this narrative review, we describe the outcome of kidney function after liver transplantation, and the prognostic factors of chronic kidney disease in order to establish a risk categorization for each patient. Furthermore, we discuss therapeutic options to prevent kidney dysfunction in this context, and highlight the indications of combined liver–kidney transplantation.

Acute kidney injury and chronic kidney disease after liver transplant: A retrospective observational study

BACKGROUND AND RATIONALE

Chronic kidney disease remains an important risk factor for morbidity and mortality among LT recipients, but its exact incidence and risk factors are still unclear.

MATERIAL AND METHODS

We carried out a retrospective cohort study of consecutive adults who underwent liver transplant (January 2009-December 2018) and were followed (at least 6 months) at our institution. CKD was defined following the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 Clinical Practice Guidelines. Long-term kidney function was classified into 4 groups: no CKD (eGFR, ≥60mL/min/1.73m2), mild CKD (eGFR, 30-59mL/min/1.73m2), severe CKD (eGFR, 15-29mL/min/1.73m2), and end-stage renal disease (ESRD).

RESULTS

We enrolled 410 patients followed for 53.2±32.6 months. 39 had CKD at baseline, and 95 developed de novo CKD over the observation period. There were 184 (44.9%) anti-HCV positive, 47 (11.5%) HBsAg positive, and 33 (8.1%) HBV/HDV positive recipients. Recipient risk factors for baseline CKD were advanced age (P=0.044), raised levels of serum uric acid (P<0.0001), and insulin dependent DM (P=0.0034). Early post-transplant AKI was common (n=95); logistic regression analysis found that baseline serum creatinine was an independent predictor of early post-LT AKI (P=0.0154). According to our Cox proportional hazards model, recipient risk factors for de novo CKD included aging (P<0.0001), early post-transplant AKI (P=0.007), and baseline serum creatinine (P=0.0002). At the end of follow-up, there were 116 LT recipients with CKD - 109 (93.9%) and 7 (6.1%) had stage 3 and advanced CKD, respectively. Only two of them are undergoing long-term dialysis.

CONCLUSION

The incidence of CKD was high in our cohort of LT recipients, but only a slight decline in kidney function over time was recorded. Prevention of post-transplant AKI will improve kidney function in the long run. We need more studies to analyze the function of kidneys among LT recipients over extended follow-ups and their impact on mortality.

Health Care Resource Use and Cost Burden of Chronic Kidney Disease in Patients With Chronic Liver Disease: A Real-World Claims Analysis

Chronic Liver Disease (CLD) is associated with an increased risk of chronic kidney disease (CKD). However, the health care burden of CKD in the CLD spectrum is unknown. We aimed to evaluate the health care use and cost burdens associated with CKD in patients with CLD in the United States by using real-world claims data. We analyzed data from the Truven Health MarketScan Commercial Claims database from 2010 to 2015. A total of 19,664 patients with CLD with or without comorbid CKD were identified using International Classification of Diseases, Ninth Revision, codes and matched 1:1 by sociodemographic characteristics and comorbidities using propensity scores. Total and service-specific unadjusted and adjusted health care parameters were analyzed for the 12 months following an index date selected at random to capture whole disease burdens. In CLD, comorbid CKD was associated with a higher annual number of claims per person (CKD vs. no CKD, 69 vs. 55) and higher total annual median health care costs (CKD vs. no CKD, $21,397 vs. $16,995). A subanalysis stratified by CKD category showed that health care use and cost burden in CLD increased with disease stage, with a peak 12-month median cost difference of $77,859 in patients on dialysis. The adjusted per person annual health care cost was higher for CKD cases compared to controls ($35,793 vs. $24,048, respectively; P < 0.0001). Stratified by the type of CLD, the highest between-group adjusted cost differences were for cirrhosis, viral hepatitis, hemochromatosis, and nonalcoholic fatty liver disease. Conclusion: CKD is a cost multiplier in CLD. The CKD health care burden in liver disease differs by the type of CLD. Improved CKD screening and proactive treatment interventions for at-risk patients can limit the excess burden associated with CKD in patients with CLD.

Chronic Kidney Disease after Liver Transplantation: Recent Evidence

Chronic kidney disease is a common complication after liver transplantation with an incidence ranging between 20% and 80%. Studies of renal function after liver transplantation have yielded conflicting results: the wide range in incidence rates of chronic kidney disease (CKD) following liver transplantation is related to the methods for measuring kidney function, and various criteria for defining renal dysfunction, among others. An important cause of CKD among liver transplant recipients is calcineurin inhibitor-based immunosuppression. Additional predictors of CKD post-liver transplantation include pre-transplant kidney function, peri-operative acute kidney failure, age, and hepatitis C. A recent meta-analysis of observational studies revealed that, in the subgroup of studies provided with glomerular filtration rate at baseline, the summary estimate of relative risk and 95% confidence intervals (CI) for developing chronic renal failure among liver transplant recipients with diminished renal function at transplant was 2.12 (95% CI, 1.01–4.46, p=0.047). Acute renal insufficiency is common immediately after liver transplantation, whereas the course of CKD after liver transplantation appears progressive over time. Only preliminary information exists on kidney pathological findings in recipients of liver transplants with CKD. Introduction of the Model for End-stage Liver Disease for the allocation of liver grafts has not increased the occurrence of renal dysfunction following liver transplantation. Chronic kidney disease following liver transplantation increases cardiovascular burden dramatically. The use of mycophenolic acid- or sirolimus-based immunosuppression in calcineurin-inhibitors sparing protocols is an area of intense research.

Spatial distribution of kidney disease in the contaminated site of Taranto (Italy)

BACKGROUND

Exposure to heavy metals has been associated with kidney disease. We investigated the spatial distribution of kidney disease in the industrially contaminated site of Taranto.

METHODS

Cases were subjects with a first hospital discharge diagnosis of kidney disease. Cases affected by specific comorbidities were excluded. Standardized Hospitalization Ratios (SHRs) were computed for low/high exposure area and for modeled spatial distribution of cadmium and fine particulate matter.

RESULT

Using the high/low exposure approach, in subjects aged 20-59 years residing in the high exposure area a significant excess of hospitalization was observed in males and a non-significant excess in females. No excesses were observed in subjects aged 60 years and over. The analysis by the modeling approach did not show a significant association with the greatest pollution impact area.

CONCLUSION

Due to the excesses of hospitalization observed in the high/low exposure approach, a continuing epidemiological surveillance of residents and occupational groups is warranted.

Comparing 10-yr renal outcomes in deceased donor and living donor liver transplants

Few studies have explored whether the type of LT, deceased donor LT (DDLT) or living donor LT (LDLT), impacts long-term renal outcomes. We performed a retrospective analysis of 220 LT recipients at our institution to study their renal outcomes at 10 yr. Exclusion criteria were age ≤ 18 yr, graft survival ≤ 6 months, and multiorgan transplants; 108 DDLTs and 62 LDLTs were eligible. At baseline, DDLTs had a lower eGFR than LDLTs and 10.2% of DDLTs were on dialysis as compared to 0% of LDLTs. At 10 yr, seven DDLT and three LDLT recipients required dialysis or renal transplant (p = 0.75). In recipients with graft survival >6 months, DDLTs had a slower decline in eGFR as compared to LDLTs (p < 0.01). Among LDLTs, the decline in eGFR continued over the entire 10-yr period, whereas among DDLTs, the decline in eGFR slowed significantly after six months (p = 0.01). This difference between the two groups was not seen among patients in the highest quartile of baseline eGFR. Patient survival and graft survival were similar. In conclusion, the incidence of end-stage renal disease was similar in both DDLT and LDLT patients, but LDLT recipients seem to have a more sustained decline in eGFR when compared with DDLT recipients.

The impact of gender and NASH on chronic kidney disease before and after liver transplantation

BACKGROUND & AIMS

Chronic kidney disease (CKD) after liver transplant (LT) is associated with increased long-term mortality. The impact of gender on CKD before and after LT is unknown. To further define risk factors and analyse gender differences in the incidence and progression of CKD after liver transplant.

METHODS

Four hundred and fifty-five consecutive adult primary solitary LT recipients were included. Iothalamate clearance tests performed over time were analysed.

RESULTS

Mean age was 51.4 ± 10.4 years with 63% males. A percentage of 29.1% of females and 21.1% of males had a GFR<60 ml/min/1.73 m(2) and 10.2% of females and 5.9% of males had GFR<30 ml/min/1.73 m(2) prior to transplant. At 1 year, 52.6% of recipients tested (69.6% females, 43.0% males) had GFR<60 ml/min/1.73 m(2) and 7.3% (11.6% females, 4.9% males) had GFR<30 ml/min/1.73 m(2) . Pre-LT GFR<60 ml/min/1.73 m(2) [OR 3.28, (1.76-6.10), P ≤ 0.001], female gender (OR 2.96, (1.72-5.10), P < 0.001) and age [OR 1.09, (1.05-1.12), P < 0.001] were independently predictive of stage ≥3 CKD at 1 year post-LT. Female gender [OR 2.52, (1.25-4.71), P = 0.004], age [OR 1.05, (1.02-1.08), P = 0.003] and NASH [OR 2.95, (1.06-8.21), P = 0.039] were independently predictive of ≥stage 3 CKD at 5 years post-LT. Pre-LT diabetes was associated with stage 4 CKD at 5 years [OR 2.91, (1.33-6.36), P = 0.008] post-LT.

CONCLUSIONS

In addition to age and pre-LT CKD, female gender and NASH are independent predictors of ≥stage 3 CKD post-LT. Gender-based approaches to optimize modifiable risk factors are needed to improved post-transplant renal function.

Clinical usefulness of kidney biopsy in liver transplant recipients with renal impairment

Background

Chronic kidney disease is a common complication after liver transplantation. In this study, we analyzed the results of kidney biopsy in liver transplantation recipients with renal impairment.

Methods

Between 1999 and 2012, 544 liver transplants were performed at our hospital. We retrospectively analyzed the clinical and histological data of 10 liver transplantation recipients referred for kidney biopsy.

Results

The biopsies were performed at a median of 24.5 months (range, 3–73 months) after liver transplantation. The serum creatinine level was 1.81±0.5 mg/dL at the time of kidney biopsy. There were no immediate complications. The most common diagnosis was glomerulonephritis (GN), such as immunoglobulin A nephropathy (n=4), mesangial proliferative GN (n=1), focal proliferative GN (n=1), and membranous GN (n=1). Typical calcineurin inhibitor (CNI)-induced nephrotoxicity was detected in three cases (30%). Chronic tissue changes such as glomerulosclerosis, interstitial fibrosis, and tubular atrophy were present in 90%, 80%, and 80% of cases, respectively, and mesangial proliferation was detected in 40% of cases. We began treatment for renal impairment based on the result of kidney biopsy; for example, angiotensin-receptor blockers or steroids were prescribed for GN, and the CNI dose was reduced for CNI nephrotoxicity. As a result, eight of 10 patients showed improvement in glomerular filtration rate, but two progressed to end-stage renal disease.

Conclusion

Kidney biopsy is a safe and effective method for determining the cause of renal impairment after liver transplantation. Management of patients based on the result of kidney biopsy may improve renal outcomes.

Low estimated glomerular filtration rate and chronic kidney failure following liver transplant: a retrospective cohort study

BACKGROUND

Patients undergoing orthotropic liver transplant (LTx) often present with chronic kidney disease (CKD). Identification of patients who will progress to end-stage renal disease (ESRD) might allow not only the implementation of kidney protective measures but also simultaneous kidney transplant.

STUDY DESIGN

Retrospective cohort study in adults who underwent LTx at a single center. ESRD, death, and composite of ESRD or death were studied outcomes.

RESULTS

331 patients, who underwent LTx, were followed up for 2.6 ± 1.4 years; 31 (10%) developed ESRD, 6 (2%) underwent kidney transplant after LTx and 25 (8%) remained on chronic hemodialysis. Patients with preoperative eGFR lesser than 60 ml/min per 1.73 m2 had a 4-fold increased risk of developing ESRD after adjustment for sex, diabetes mellitus, APACHE II score, use of nephrotoxic drugs, and severe liver graft failure (HR = 3.95, 95% CI 1.73, 9.01; p = 0.001). Other independent risk factors for ESRD were preoperative diabetes mellitus and post-operative severe liver graft dysfunction.

CONCLUSION

These findings emphasize low eGFR prior to LTx as a predictor for ESRD or death. The consideration for kidney after liver transplant as a treatment modality should be taken into account for those who develop chronic kidney failure after LTx.

Predicting end-stage renal disease after liver transplant

Few equations have been developed to predict end-stage renal disease (ESRD) after deceased donor liver transplant. This retrospective observational cohort study analyzed all adult deceased donor liver transplant recipients in the Scientific Registry of Transplant Recipients (SRTR) database, 1995-2010. The prediction equation for ESRD was developed using candidate predictor variables available in SRTR after implementation of the allocation policy based on the model for end-stage liver disease. ESRD was defined as initiation of maintenance dialysis therapy, kidney transplant or registration on the kidney transplant waiting list. We used Cox proportional hazard models to develop separate equations for assessing risk of ESRD by 6 months posttransplant and between 6 months and 5 years posttransplant. Variables in the 6-month equation included recipient age, history of diabetes, history of dialysis before liver transplant, history of malignancy, body mass index, serum creatinine and liver donor risk index. Variables in the 6-month to 5-year equation included recipient race, history of diabetes, hepatitis C status, serum albumin, serum bilirubin and serum creatinine. The prediction equations have good calibration and discrimination (C statistics 0.74-0.78). We have produced risk prediction equations that can be used to aid in understanding the risk of ESRD after liver transplant.

Long-term outcome after liver transplantation

Liver transplantation is a life-saving therapy for patients with end-stage liver disease, acute liver failure, and liver tumors. Over the past 4 decades, improvements in surgical techniques, peritransplant intensive care, and immunosuppressive regimens have resulted in significant improvements in short-term survival. Focus has now shifted to addressing long-term complications and improving quality of life in liver recipients. These include adverse effects of immunosuppression; recurrence of the primary liver disease; and management of diabetes, hypertension, dyslipidemia, obesity, metabolic syndrome, cardiovascular disease, renal dysfunction, osteoporosis, and de novo malignancy. Issues such as posttransplant depression, employment, sexual function, fertility, and pregnancy must not be overlooked, as they have a direct impact on the liver recipient's quality of life. This review summarizes the latest data in long-term outcome after liver transplantation.

Clinical significance of post kidney transplant de novo DSA in otherwise stable grafts

We have previously shown poor outcomes in a cohort of kidney recipients with de novo donor specific anti-HLA antibodies (DSA) detected via post-transplant screening, were due to prior acute rejection (AR) episodes. In this report, we sought to identify DSA characteristics associated with poor outcomes in the absence of AR. All living and cadaveric donor kidney/ kidney-pancreas recipients from 9/07 to 10/09 were screened for class I and II DSA at 1, 6, 12, and 24 months post-transplant, in addition to whenever clinically indicated, using single antigen beads and Luminex technology. Mean florescence intensity (MFI) > 500 was defined as positive. Compared to DSA(-) patients, those who developed both class I and II DSA experienced worse graft survival (p < .001). Graft survival in those with class I or II alone was unchanged. Patients with DSA MFI > 6000 experienced worse 1-year modification of diet in renal disease glomerular filtration rate (MDRD GFR) (p = 0.022) and 2-year graft survival (p = .026) compared to DSA(-) patients, whereas graft survival in groups with lower antibody strength was not statistically different. The effect of DSA class and strength was lost when removing patients with AR from the analysis. In sum, with a mean follow-up of 29 months, the presence of combined de novo class I and II DSA as well as DSA with MFI > 6000, is associated with worse graft outcomes only in association with AR episodes.

Glomerular and tubular function following orthotopic liver transplantation in children treated with tacrolimus

The aim of this study was to analyze the impact of TAC on medium term (three-yr follow-up) renal function in pediatric liver transplant (OLT) recipients. Glomerular and tubular indices were retrospectively analyzed in 24 consecutive OLT pediatric recipients on TAC. CrCl increased significantly each month post-OLT (p = 0.003), with a trend toward significance between pre-OLT and 36 months (p = 0.17). There was no correlation between CrCl and TAC troughs (p = 0.783). Sixteen percent of patients had CrCl <60 mL/min/1.73 m(2) pre-OLT vs. none at 36 months post-OLT. TRP values were normal throughout the study. UPr/Cr decreased insignificantly over time and correlated significantly with TAC trough levels (p = 0.031). UCa/Cr values normalized by the third-month post-OLT, decreasing significantly over the time (p = 0.000) but did not correlate with TAC troughs. At three months post-OLT, 65.2% of patients needed antihypertensive therapy, and no patients needed more than one antihypertensive treatment after one yr. Despite nephrotoxic side effects in the early postoperative phase, this study shows that 65.5% patients had a normal renal function by three yr post-OLT. Tubular indices correlated with TAC trough levels.

Pre-transplant kidney function predicts chronic kidney disease after liver transplant: meta-analysis of observational studies

BACKGROUND

Chronic kidney disease is a common problem in long-term survivors after liver transplantation. Several studies to clarify the risk factors for incidence of chronic kidney disease among liver transplant recipients, including preoperative kidney function, have yielded conflicting results.

AIM

The aim of this study was to conduct a systematic review of the published medical literature on the impact of pre-transplant kidney function on the occurrence of chronic kidney disease after liver transplantation.

METHODS

Study-specific relative risks were weighted by the inverse of their variance to obtain fixed- and random-effects pooled estimates for incidence of chronic kidney disease across the published studies. The relative risk of chronic kidney disease after liver transplantation according to pre-transplant glomerular filtration rate was regarded as the most reliable outcome end-point.

RESULTS

We identified seven studies (38,036 unique liver transplant recipients). A stratified analysis including only studies provided with glomerular filtration rate at transplant reported that the summary estimate of relative risk and 95% confidence intervals (CIs) for developing chronic renal failure among liver transplant recipients with diminished renal function at transplant was 2.12 (95% CI, 1.01; 4.46) (random-effects model). The p value for study heterogeneity was significant (p = 0.0001). Post-transplant chronic kidney disease shows impact on survival; the summary estimate for the adjusted relative risk of all-cause mortality with chronic kidney disease after liver transplant was 4.35 (95% confidence Intervals, 3.34; 5.66), p = 0.0001 (random-effects model).

CONCLUSIONS

An increased risk of chronic kidney disease frequently exists among liver transplant recipients with reduced renal function at transplant. The occurrence of chronic kidney disease after liver transplantation has a major impact on mortality. Additional studies are needed to understand better the natural history of chronic kidney disease among liver transplant recipients.