Chronic Kidney Disease—A Common and Serious Complication After Intestinal Transplantation

Risk factors for renal dysfunction after isolated intestinal transplantation

INTRODUCTION

Kidney dysfunction is a known complication of intestinal transplantation; however, the rate of development and risk factors for chronic kidney disease (CKD) remain poorly defined.

METHODS

This was a single-center retrospective review of isolated adult intestinal allograft recipients from 2011 to 2019. Patients who died or experienced graft loss within 1-year or had a prior transplant were excluded. Estimated glomerular filtration rate (eGFR) was calculated using the CKD-EPI equation at 0-, 6- and 12-months post-transplant, and multivariable linear regression was performed to identify variables associated with adjusted eGFR at 1-year. Independent variables included age, ethnicity, BMI, history of diabetes/hypertension, vasopressor use, TPN and stoma days, urinary or bloodstream infections, intravenous contrast exposure, rejection, concomitant immunosuppression, and time above the therapeutic range of tacrolimus. Variables with a p < .1 in univariate analysis were considered for multivariable modeling.

RESULTS

Thirty-three patients were included with a mean age of 43.9 ± 13.0. A mean 42.3% decline in eGFR was observed at 1-year post-transplant, with 15.2% of patients developing new stage 4/5 CKD. Factors associated with a greater decline in adjusted eGFR in the univariate model included increasing age, decreased BMI, stoma days, and vasopressor use. In the adjusted multivariable model patient age (β = -.77, p < .01) and stoma days (β = -.06, p < .01) remained significant. Tacrolimus and sirolimus exposure were not associated with decline in eGFR at 1 year.

CONCLUSIONS

Renal dysfunction is common following intestinal transplantation. The need for stoma creation should be carefully considered, and reversal should be performed when feasible for renal protection.

Long-term Course of Kidney Function in Uterus Transplant Recipients Under Treatment With Tacrolimus and After Transplantectomy: Results of the First Clinical Cohort

Background

Chronic kidney disease is common after non-renal solid organ transplantation, mainly secondary to calcineurin inhibitors toxicity. Uterus transplantation (UTx) is an innovative treatment for women with absolute uterine factor infertility. UTx is exclusive because it is transient with the absence of lifelong immunosuppression and is performed in young healthy participants. Therefore, UTx provides a unique setting for evaluating the effect of time-limited calcineurin inhibitors treatment on recipients' kidney function.

Methods

In the first UTx cohort worldwide, we studied kidney function using estimated glomerular filtration rate (eGFR) in 7 women over a median follow-up of 121 (119-126) mo.

Results

Median eGFR (mL/min/1.73 m2) of the cohort was 113 at UTx, which declined to 74 during month 3, 71 at months 10-12, 76 at hysterectomy (HE), and 83 at last follow-up. Median duration of tacrolimus exposure was 52 (22-83) mo, and median trough levels (µg/L) were 10 during month 3 and 5.8 at HE. Between UTx and month 3, decline in kidney function was observed in all 7 participants with a median eGFR slope for the whole cohort of -24 mL/min/1.73 m2, which declined further by -4 mL/min/1.73 m2 until months 10-12. Thereafter, eGFR slope improved in 3 participants, remained stable in 3, and worsened in 1 until HE/tacrolimus discontinuation, after which it improved in 2. Eventually, between UTx and last follow-up, 4 of 7 participants had a decline in their eGFR, the median annual eGFR slope being negative at -1.9 mL/min/1.73 m2/y for the whole group.

Conclusions

Kidney function declined in all recipients early after UTx followed by a persistent long-term decrease in majority, despite transplantectomy and discontinuation of immunosuppression. Thus, UTx may incur an increased risk of chronic kidney disease even in this young and healthy population, highlighting the importance of close surveillance of kidney function and minimization of tacrolimus exposure.

Kidney disease in non-kidney solid organ transplantation

Kidney disease after non-kidney solid organ transplantation (NKSOT) is a common post-transplant complication associated with deleterious outcomes. Kidney disease, both acute kidney injury and chronic kidney disease (CKD) alike, emanates from multifactorial, summative pre-, peri- and post-transplant events. Several factors leading to kidney disease are shared amongst solid organ transplantation in addition to distinct mechanisms unique to individual transplant types. The aim of this review is to summarize the current literature describing kidney disease in NKSOT. We conducted a narrative review of pertinent studies on the subject, limiting our search to full text studies in the English language. Kidney disease after NKSOT is prevalent, particularly in intestinal and lung transplantation. Management strategies in the peri-operative and post-transplant periods including proteinuria management, calcineurin-inhibitor minimization/ sparing approaches, and nephrology referral can counteract CKD progression and/or aid in subsequent kidney after solid organ transplantation. Kidney disease after NKSOT is an important consideration in organ allocation practices, ethics of transplantation. Kidney disease after SOT is an incipient condition demanding further inquiry. While some truths have been revealed about this chronic disease, as we have aimed to describe in this review, continued multidisciplinary efforts are needed more than ever to combat this threat to patient and allograft survival.

Delayed introduction of sirolimus in paediatric intestinal transplant recipients: indications and long-term benefits

To review our experience using sirolimus in a single centre paediatric intestinal transplantation cohort. Intestinal transplant patients with more than 3 months follow-up were divided into two groups according to their immunosuppression regimen: tacrolimus, (TAC group, n = 45 grafts) or sirolimus (SRL group, n = 38 grafts), which included those partially or completely converted from tacrolimus to sirolimus. The indications to switch were tacrolimus side effects and immunological complications. Survival and complications were retrospectively analysed comparing both groups. SRL was introduced 9 months (0 months-16.9 years) after transplant. The main cause for conversion was worsening renal function (45%), followed by haemolytic anaemia (21%) and graft-versus-host-disease (16%). Both groups showed a similar overall patient/graft survival (P = 0.76/0.08) and occurrence of rejection (24%/17%, P = 0.36). Immunological complications did not recur after conversion. Renal function significantly improved in most SRL patients. After a median follow-up of 65.17 months, 28/46 survivors were on SRL, 26 with monotherapy, with good graft function. Over one-third of our patients eventually required SRL conversion that allowed to improve their kidney function and immunological events, without entailing additional complications or survival impairment. Further trials are warranted to clarify the potential improvement of the standard tacrolimus maintenance by sirolimus conversion or addition.

Efficacy and safety of mammalian target of rapamycin inhibitors following intestinal and multivisceral transplantation

This is a descriptive study reviewing the outcomes of mammalian target of rapamycin inhibitors (mTORs) in intestinal (IT) and multivisceral transplantation (MVT). This study included 22 patients, 20 adults, and two children, and an overall mean age of 46 years old at the time of transplantation. Twelve patients (54.5%) received IT, and the remainder (45.5%) MVT. The mean time between transplantation and mTORs initiation was 24 months. The indication was worsening renal function in 13 patients (59%), with 9/13 (69.2%) noted to have an increase in glomerular filtration rate of at least 10 ml/min/1.73m² . The indication for four patients (18.2%) was a history of neuroendocrine tumor. After mTOR initiation, 50% of patients were reduced or weaned off tacrolimus and 13.7% off prednisone. mTORs were discontinued in 11/22 patients. Six patients (54.5%) stopped due to side effects, two (18.1%) for surgery, and one (9%) for acute cellular rejection. Side effects were edema (33.3%), headaches (33.3%), diarrhea (16.7%), and oral ulcers (16.7%). The average duration of mTORs prior to discontinuation due to side effects was 7 months. mTORs may function in their own niche of patients due to the potential renal safety profile, but use is most limited by tolerance to side effects.

Decline in renal function following intestinal transplant: is the die cast at 3 months?

INTRODUCTION

This study reports the incidence of chronic kidney disease (CKD) after intestinal transplant (IT) at a single, adult center in the United Kingdom.

METHODS

A retrospective review of IT was undertaken. Methods of renal function assessment pre-transplant were compared. Post-transplant renal function and renal sparing strategies were analyzed.

RESULTS

There was a 30% variation (p < .001) in estimated glomerular filtration rate (eGFR) and normalized GFR at assessment. In the first 3 months post-transplant, there was a 40% decline in eGFR which was irreversible. Liver inclusion was not protective with similar eGFR at 3 months (60 ml/min/1.73 m² ) compared with IT (55 ml/min/1.73 m² ). The rate of decline in the first 2 months was less in multivisceral transplant (MVT; 21%) than IT (52%) suggesting surgical magnitude did not contribute. Thirty percentage of recipients had acute cellular rejection post-transplant; 58% of these were in the first 3 months with a higher proportion in MVT (64%) than IT (27%). Tacrolimus exposure did not correlate with decline in renal function over the first 3 months post-transplant.

CONCLUSION

We demonstrated a 40% decline in renal function within 3 months post-IT which was irreversible despite renal sparing strategies. Early intervention should be considered in patients with an acute decline in this post-transplant period.

Chronic Rejection After Intestinal Transplant: Where Are We in Order to Avert It?

Chronic rejection affects the long-term survival of all solid organ transplants and, among intestinal allografts, occurs in up to 10% of the recipients. The insidious clinical evolution of the chronic allograft enteropathy, the absence of noninvasive biomarkers, and the late endoscopic findings delay its diagnosis. No pharmacological approach has been proven effective, and allograft removal nowadays still represents the only available therapy. The inclusion of the liver in the visceral allograft appears to be the only intervention affecting the development of chronic rejection, as revealed by large-center studies and registry reports. A significant body of evidence emerged from the experimental setting and provided essential knowledge on the complex mechanisms behind the development of chronic allograft enteropathy. More recently, donor-specific antibodies have been suggested as an early, key element in the natural history of chronic allograft enteropathy and several novel approaches, tackling the antibody-mediated graft injury, have gained acceptance in clinical settings and are believed to impact on chronic rejection. The inclusion of a liver allograft is advocated when re-transplanting a sensitized recipient, due to its protective effect against humoral immunity. Multicenter trials are required to understand and tackle chronic rejection, and find the therapeutic answer to this clinical dilemma.

Intestinal transplantation

Intestinal transplantation has now emerged as a lifesaving therapeutic option and standard of care for patients with irreversible intestinal failure. Improvement in survival over the years has justified expansion of the indications for intestinal transplantation beyond the original indications approved by Center for Medicare and Medicaid services. Management of patients with intestinal failure is complex and requires a multidisciplinary approach to accurately select candidates who would benefit from rehabilitation versus transplantation. Significant strides have been made in patient and graft survival with several advancements in the perioperative management through timely referral, improved patient selection, refinement in the surgical techniques and better understanding of the immunopathology of intestinal transplantation. The therapeutic efficacy of the procedure is well evident from continuous improvements in functional status, quality of life and cost-effectiveness of the procedure. This current review summarizes various aspects including current practices and evidence based recommendations of intestinal transplantation.

Fifteen years' experience of intestinal and multivisceral transplantation in the Nordic countries

OBJECTIVE

Intestinal and multivisceral transplantation have gained acceptance as treatment modalities for patients with: intestinal failure and life-threatening complications of parenteral nutrition (PN), rare cases of vascular abdominal catastrophes and selected cases of low-grade neoplastic tumors such as neuroendocrine pancreatic tumors and desmoids involving the mesenteric root. The aim was to describe the survival and nutritional outcome in the transplanted Nordic patients and the complications attributed to this procedure.

METHOD

The authors included all Nordic patients transplanted between January 1998 and December 2013. Information on patients transplanted outside the Nordic region was collected through questionnaires.

RESULTS

A total of 34 patients received different types of intestinal allografts. Currently, there are two Nordic transplant centers (n = 29) performing these procedures (Gothenburg, Sweden n = 24, Helsinki, Finland n = 5). The remaining five patients were transplanted in the USA (n = 3) and the UK (n = 2). Most patients were transplanted for life-threatening failure of PN (70%) caused primarily by intestinal motility diseases (59%). Allograft rejection was the most common complication and occurred in 79% of the patients followed by post-transplantation lymphoproliferative disorders (21%) and graft-versus-host disease (18%). The 1- and 5-year survival was 79% and 65% respectively for the whole cohort and nutritional autonomy was achieved in 73% of the adults and 57% of the children at 1 year after transplantation.

CONCLUSION

This collective Nordic experience confirms that intestinal transplantation is a complex procedure with many complications, yet with the possibility to provide long-term survival in selected conditions previously considered untreatable.

Effect of age on native kidney function after adult intestinal transplants on long-term follow-up

BACKGROUND

Kidney function usually deteriorates after intestinal transplant, with prevalence of renal failure almost 20% after 5 years. We report our results on adults from single institution over >10 years.

METHODS

Forty-six patients were transplanted with 22 survivors; we divided them in 2 groups: Group 1, recipients with creatinine>1.2 mg/dL (normal, 0.50-1.2) and Group 2, normal creatinine. Group 1 included 12 patients (9 males) with a mean age of 42.8 years; all lived at home, with normal creatinine at transplant (apart from 1 patient with a creatinine of 1.6 mg/dL), and were mainly transplanted for short bowel syndrome. One underwent retransplantation. Immunosuppression was based on alemtuzumab (8 recipients) plus tacrolimus (FK). Group 2 included 10 patients (6 males) with a mean age of 34.7 years; all lived at home, had normal creatinine at transplantation, and were mainly transplanted for short bowel syndrome. Immunosuppression was mainly based on alemtuzumab (8 recipients) plus FK.

RESULTS

There were no relevant differences between the 2 groups regarding number of recipients, sex, baseline creatinine at transplant, reason for transplantation, retransplantation, immunosuppression, antifungal or antiviral therapy, hospitalization, total parenteral nutrition (or fluids), or stoma. The only relevant difference was age (P=.04); patients with deteriorated kidney function or altered creatinine were found to be older.

Renal function and histology in children after small bowel transplantation

CKD is a frequent long-term complication after SBTx. CNIs are a well-known factor, but probably not the only cause. We assessed the incidence, risk factors, and severity of CKD in 27 children with SBTx (15 combined liver/SBTx) and prednisone/TAC-based maintenance immunosuppression. Median follow-up was seven yr (3-21). A renal biopsy was performed in 14 patients, 1-18 yr post-SBTx. A reduced GFR was observed in 17 children (63%) during the follow-up with none requiring dialysis. CNI toxicity was observed in 11/14 biopsies, as early as two yr post-transplant, and could occur with a normal mGFR. The dose of TAC was reduced by 50% in 13 patients with CKD and/or significant kidney histological lesions, and six were also given MMF. This led to a significant improvement in renal function: mGFR normalized in eight patients and improved or stabilized in five. No rejection occurred. At last follow-up, 37% had CKD stage 2 and 15% had CKD stage 3. In conclusion, CKD is frequent in children after SBTx and probably multifactorial. Less nephrotoxic immunosuppressive protocols may improve mGFR and should be further considered. The kidney histology helps in designing personalized immunosuppression strategies for patients.

Risk factors for native kidney dysfunction in patients with abdominal multivisceral/small bowel transplantation

Kidney dysfunction is a recognized complication after non-renal solid organ transplantation, particularly after intestinal transplant. In our study, we reviewed data on 33 multivisceral transplant (MVT)- and 15 isolated small bowel (ISB)-transplant patients to determine risk factors for kidney dysfunction. Kidney function was estimated by modified diet in renal disease (MDRD) and Schwartz formula for adults and children, respectively. Acute kidney injury (AKI) was defined as an increase in the serum Cr (sCr) greater than twofold. Kidney function declined significantly at one yr after transplantation with 46% of subjects showing an estimated GFR (eGFR) <60 mL/min. Patients with an episode of AKI were more likely to have reduced eGFR than those without AKI (p < 0.025). In linear regression analyses, age, pre-transplant sCr, eGFR at postoperative day (POD) 30, 90, 180, 270, and tacrolimus level at POD 7 showed significant correlation with one yr post-transplant eGFR (p < 0.05). Pediatric patients and patients with MVT had lesser decline in kidney function compared with adults or patients with ISB. In conclusion, risk factors for post-transplant kidney dysfunction in intestinal transplantation included age, pre-transplant sCr, AKI episode, eGFR at POD 30, 90, 180, 270, and tacrolimus level at POD 7.

The use of sirolimus as a rescue therapy in pediatric intestinal transplant recipients

To review our experience with SRL as a second-line therapy in our series of 45 SBTx recipients (1997-2009). Retrospective review of five children converted to SRL: 3 M/2 F; median of three yr old (range 20 months-18 yr); rescue indications, adverse events with SRL, resolution of tacrolimus-related side effects, incidence of rejection, PTLD, or GVHD were summarized. Tacrolimus was discontinued (average 13 months after transplant) because of refractory hemolytic anemia in four patients with decreased renal function and because of advanced renal failure and unclear neutropenia in one. PTLD and GVHD had been previously diagnosed in two. Tacrolimus-related side effects disappeared in all five although other immunosuppressants and splenectomy were used simultaneously or later in most of them. Adverse events reported after the conversion were infections (tuberculosis and Pneumocystis carinii in two) and mild hypertriglyceridemia. No rejection, GVHD, or PTLD episode was observed. Four patients are alive with excellent quality of life (median follow-up 18 months). Sirolimus is a safe rescue therapy in SBTx children when tacrolimus is not well tolerated. Renal function and hematologic disorders seem to improve, although other simultaneous strategies could be also involved. Further studies could demonstrate its efficacy as a first-line treatment.