Renal Dysfunction Following Adult Intestinal Transplant Under Tacrolimus-Based Immunosuppression

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.

Present state of intestinal transplantation in Japan

INTRODUCTION

Intestinal transplantation (ITx) is the ultimate treatment for intestinal failure (IF). In Japan, most cases of IF are a result of pediatric disease, including secondary or congenital intestinal disease or allied disorders of Hirschsprung's disease. Here, we report the results of the Japanese ITx registry.

METHODS

A web-based survey form was completed. We investigated the number, age, sex, indication, surgical procedure, immunosuppressants, postoperative course, and the effects of transplantation in patients who underwent cadaveric or living-donor ITx.

RESULTS

By the end of 2022, 42 cases of ITx have been performed in 38 patients in Japan. The donor sources included cadavers (29 cases) and living donors (13 cases). The surgical method was isolated ITx (N = 40) and combined liver and ITx (n = 2). Survival rates were 92%, 73%, and 59% at 1 year, 5 years, and 10 years, respectively. Ninety percent of patients completely discontinued parenteral nutrition. Approximately 80% of the patients had a performance status of 1 or less, indicating that the QOL of patients after ITx was extremely good.

CONCLUSION

The results of ITx are acceptable to treat IF patients and the QOL after transplantation is also good.

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.

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.

Nephrocalcinosis and Renal Dysfunction in Pediatric Intestinal Failure

BACKGROUND

Outcomes of pediatric intestinal failure (PIF) have improved recently, with other comorbidities, such as increased echogenicity/nephrocalcinosis on ultrasound (US) in long-term survivors now evident. We evaluated the significance of nephrocalcinosis over time in PIF and its impact on renal function.

METHODS

Retrospective analysis on a cohort of PIF patients was performed. Presence of nephrocalcinosis and/or increased renal echogenicity (identified on US), estimated glomerular filtration rate (eGFR; ml · min · 1.73 m2), renal tubular function, PN volume (ml · kg · day) and PN exposure time (hours/day) were reviewed annually over a follow-up period of 2 years. Outcomes in the nephrocalcinosis versus normal US groups were compared.

RESULTS

Forty patients (28 boys, median age 2.7 years) were followed for 2 years. Fifteen (38%) had either increased echogenicity or nephrocalcinosis (group 1) at initial US. US were normal in the remaining 25 (62%) on initial assessment (group 2). eGFR did not differ between group 1 and group 2 at baseline (118 vs 133, P = 0.51) and year 2 (130 vs 131, P = 1.00). The percentage of patients with abnormal markers of tubular function was similar in both groups at year 2 (high urine calcium: creatinine 33 versus 30, P = 0.83; high urine calcium: citrate 39 versus 42, P = 0.87; low urine citrate: creatinine 15 versus 17, P = 1.00; high urine oxalate: creatinine 39 versus 25, P = 0.77).

CONCLUSIONS

A large proportion of PIF patients with a history of parenteral nutrition (PN) exposure have nephrocalcinosis and/or increased echogenicity on US. Over a 2-year follow-up period, however, these abnormalities had no impact on eGFR or renal tubular function.

Outcomes of Adult Intestinal Transplant Recipients Requiring Dialysis and Renal Transplantation

Supplemental digital content is available in the text.

Background

Data on dialysis and renal transplantation (RT) after intestinal transplantation (IT) are sparse. Whether changes in immunosuppression and surgical techniques have modified these outcomes is unknown.

Methods

Two hundred eighty-eight adult intestinal transplants performed between 1990 and 2014 at the University of Pittsburgh were analyzed for incidence, risk factors and outcomes after dialysis and RT. Cohort was divided into 3 eras based on immunosuppression and surgical technique (1990-1994, 1995-2001, and 2001-2014). Receiving RT, or dialysis for 90 days or longer was considered as end-stage renal disease (ESRD).

Results

During a median follow-up of 5.7 years, 71 (24.7%) patients required dialysis, 38 (13.2%) required long-term dialysis and 17 (6%) received RT after IT. One-, 3-, and 5-year ESRD risk was 2%, 7%, and 14%, respectively. No significant era-based differences were noted. Higher baseline creatinine (hazard ratio [HR], 3.40 per unit increase, P < 0.01) and use of liver containing grafts (HR, 2.01; P = 0.04) had an increased ESRD risk. Median patient survival after dialysis initiation was 6 months, with a 3-year survival of 21%. Any dialysis (HR, 12.74; 95% CI 8.46-19.20; P < 0.01) and ESRD (HR, 9.53; 95% CI, 5.87-15.49; P < 0.01) had higher mortality after adjusting for covariates. For renal after IT, 1- and 3-year kidney and patient survivals were 70% and 49%, respectively. All graft losses were from death with a functioning graft, primarily related to infectious complications (55%).

Conclusions

In intestinal transplant recipients, renal failure requiring dialysis or RT is high and is associated with increased mortality. Additionally, the outcomes for kidney after IT are suboptimal due to death with a functioning graft.

The current therapeutic options for Crohn's disease: from medical therapy to intestinal transplantation

Crohn's disease (CD) has an annual incidence per 100.000 person-year of 20.2 in North America and 12.7 in Europe, and the purpose of this review is to evaluate its medical management, from diagnosis to transplant. Pharmacologic manipulation with nutritional care aims to achieve and maintain remission, but more than half of patients will undergo an intestinal resection, very often repeated over time. They could experience short bowel syndrome (SBS) requiring total parenteral nutrition (TPN). Intestinal transplantation (ITx) represents an alternative in case of irreversible intestinal failure (IF) with life-threatening TPN complications. Patient survival after ITx is 79%, 53% and 43% at 1, 3 and 5 years respectively, with no differences among ITx for other disorders. Areas covered: The research discussed medical therapy with nutritional support, evaluating the role of endoscopy, surgery and transplant in CD. A systematic literature review was conducted using the PubMed search engine up to May 31^th, 2017 without restriction of the language. The decision on paper's eligibility was reached by consensus between the 3 screening authors. Expert commentary: CD treatment is mainly medical, leaving endoscopy and surgery for a complex course. ITx represents a therapeutic option if TPN complications with IF arise.

Neurodevelopmental Abnormalities and Congenital Heart Disease: Insights Into Altered Brain Maturation

In the past 2 decades, it has become evident that individuals born with congenital heart disease (CHD) are at risk of developing life-long neurological deficits. Multifactorial risk factors contributing to neurodevelopmental abnormalities associated with CHD have been identified; however, the underlying causes remain largely unknown, and efforts to address this issue have only recently begun. There has been a dramatic shift in focus from newly acquired brain injuries associated with corrective and palliative heart surgery to antenatal and preoperative factors governing altered brain maturation in CHD. In this review, we describe key time windows of development during which the immature brain is vulnerable to injury. Special emphasis is placed on the dynamic nature of cellular events and how CHD may adversely impact the cellular units and networks necessary for proper cognitive and motor function. In addition, we describe current gaps in knowledge and offer perspectives about what can be done to improve our understanding of neurological deficits in CHD. Ultimately, a multidisciplinary approach will be essential to prevent or improve adverse neurodevelopmental outcomes in individuals surviving CHD.

Prevalence of renal abnormality in pediatric intestinal failure

BACKGROUND

Outcomes of children with intestinal failure have improved over the last decade. However, with improved survival, other co-morbidities have become evident. The goal of our study was to evaluate the presence of renal nephrocalcinosis or increased echogenicity in a cohort of patients with pediatric intestinal failure (PIF).

METHODS

A cross-sectional prevalence design was performed in PIF patients followed by our intestinal rehabilitation program between 2013 and 2014. Renal function was evaluated using serum creatinine and urea, urine oxalate, creatinine, calcium, and calcium/creatinine ratios. Renal ultrasounds were performed to assess for echogenicity. Data was collected on intestinal failure related factors and nutritional intake. Data was analyzed using medians and Mann-Whitney U or proportions and chi square.

RESULTS

Fifty-four patients (median age 48months; 33 males (61%) were studied. Twenty-two patients (41%) had increased echogenicity or nephrocalcinosis on ultrasound. There were no differences in serum Creatinine or urea, but patients with nephrocalcinosis had statistically different calcium:creatinine ratio (1.69 vs 0.74; p=0.043), urine oxalate (108 vs 219; p=0.06), and serum phosphate (1.55 vs 1.75; p=0.044). Patients with echogenicity had a shorter colonic remnant (25cm vs 31cm; p=0.01), a history of longer PN exposure (928 vs 483days; p=0.05), percent PN calories (37 vs 0; p=0.05), PN h/day (13 vs 0; p=0.05), but no difference in PN Ca/phosphate/magnesium content (mmol/kg).

CONCLUSION

A large proportion of PIF patients have increased echogenicity/nephrocalcinosis on ultrasound that is associated with prolonged PN exposure. This has implications for long-term management. Regular surveillance is required, and further study is warranted to determine specific risk factors.

Nonsurgical care of intestinal and multivisceral transplant recipients: a review for the intensivist

Intestinal and multivisceral transplantation has evolved from an experimental procedure to the treatment of choice for patients with irreversible intestinal failure and serious complications related to long-term parenteral nutrition. Increased numbers of transplant recipients and improved survival rates have led to an increased prevalence of this patient population in intensive care units. Management of intestinal and multivisceral transplant recipients is uniquely challenging because of complications arising from the high incidence of transplant rejection and its treatment. Long-term comorbidities, such as diabetes, hypertension, chronic kidney failure, and neurological sequelae, also develop in this patient population as survival improves. This article is intended for intensivists who provide care to critically ill recipients of intestinal and multivisceral transplants. As perioperative care of intestinal/multivisceral transplant recipients has been described elsewhere, this review focuses on common nonsurgical complications with which one should be familiar in order to provide optimal care. The article is both a review of the current literature on multivisceral and isolated intestinal transplantation as well as a reflection of our own experience at the University of Miami.

Intestinal transplantation in children: a review of immunotherapy regimens

This review summarizes the outcomes and known adverse effects of current immunosuppression strategies in use in pediatric intestinal transplantation. Intestinal transplantation has evolved from an experimental therapy to a highly successful treatment for children with intestinal failure who have complications with total parenteral nutrition. Because of continued success with intestinal transplantation over the past decade, the focus of clinicians and researchers is shifting from short-term patient survival to optimizing long-term outcomes. Current 5-year patient and graft survival rates after intestinal transplantation are 58% and 40%, respectively, in the US; single centers have reported nearly 80% patient and 60% graft survival rates at 5 years. The immunosuppression strategy in intestinal transplantation includes a tacrolimus-based regimen, usually in conjunction with an antibody induction therapy such as rabbit-antithymocyte globulin, interleukin-2 receptor antagonists, or alemtuzumab. The use of these immunosuppressive regimens, along with improved medical and surgical care, has contributed significantly toward improved outcomes. Optimization of post-transplant immunosuppression strategies to reduce adverse effects while minimizing acute and chronic graft rejection is a strong clinical and research focus.

Intestine transplantation in the United States, 1999-2008

Improving short-term results with intestine transplantation have allowed more patients to benefit with nearly 700 patients alive in the United States with a functioning allograft at the end of 2007. This success has led to an increase in demand. Time to transplant and waiting list mortality have significantly improved over the decade, but mortality remains high, especially for infants and adults with concomitant liver failure. The approximately 200 intestines recovered annually from deceased donors represent less than 3% of donors who have at least one organ recovered. Consent practice varies widely by OPTN region. Opportunities for improving intestine recovery and utilization include improving consent rates and standardizing donor selection criteria. One-year patient and intestine graft survival is 89% and 79% for intestine-only recipients and 72% and 69% for liver-intestine recipients, respectively. By 10 years, patient and intestine survival falls to 46% and 29% for intestine-only recipients, and 42% and 39% for liver-intestine, respectively. Immunosuppression practice employs peri-operative antibody induction therapy in 60% of cases; acute rejection is reported in 30%-40% of recipients at one year. Data on long-term nutritional outcomes and morbidities are limited, while the cause and therapy for late graft loss from chronic rejection are areas of ongoing investigation.

Renal function impacts outcomes after intestinal transplantation. Transplantation. 2008;86:117-122. [PMID: 18622288 DOI: 10.1097/TP.0b013e31817d55ae]

BACKGROUND

Although renal dysfunction (RD) has been commonly associated with poor outcome after other solid organ transplants, it has not been studied in detail after intestinal transplantation (ITx). Here we provide a detailed analysis of renal function after ITx, and identify predictors of post-ITx RD.

METHODS

A retrospective analysis of patients undergoing ITx from 1991 to 2006 was performed. For each patient, the estimated glomerular filtration rate (eGFR) was compared with the normal GFR for age and gender to obtain the percent of normal eGFR. Chi-square analysis and log-rank tests were used to identify categorical variables associated with RD (eGFR <75% of normal) and to determine if RD was predictive of post-ITx survival.

RESULTS

Sixty-eight transplantations were performed in 62 patients. Overall patient survival at 1 and 5 years was 78% and 56%, respectively. Renal dysfunction was observed in 16% of patients post-ITx. The most frequent predictors of post-ITx RD were preoperative eGFR less than 75% of normal, pre-ITx location in the intensive care unit, and high-dose tacrolimus immunotherapy. An eGFR less than 75% of normal at days 7, 28, and 365 was predictive of poor patient survival (P<0.05).

CONCLUSIONS

This study provides the first detailed analysis of renal function after ITx. We identified specific risk factors for the development of RD in the first year post-ITx and found a significant association of RD with decreased long-term survival. Given the strong correlation of RD with poor outcome, preserving renal function may be key to improving long-term outcomes in ITx recipients.

Small intestine transplantation today

INTRODUCTION

Intestinal transplantation has become a life-saving therapy in patients with irreversible loss of intestinal function and complications of total parenteral nutrition.

DISCUSSION

The patient and graft survival rates have improved over the last years, especially after the introduction of tacrolimus and rapamycin. However, intestinal transplantation is more challenging than other types of solid organ transplantation due to its large amount of immune competent cells and its colonization with microorganisms. Moreover, intestinal transplantation is still a low volume procedure with a small number of transplanted patients especially in Germany. A current matter of concern is the late referral of intestinal transplant candidates.

CONCLUSION

Thus, patients often present after onset of life-threatening complications or advanced cholestatic liver disease. Earlier timing of referral for candidacy might result in further improvement of this technique in the near future.