Renal transplantation in infants

Late nephrectomy in infants with congenital nephrotic syndrome of the Finnish type

AIM

Bilateral nephrectomy is commonly performed in patients with congenital nephrotic syndrome of the Finnish type. The optimal timing of nephrectomy is unclear.

METHODS

Growth, thromboembolic events, infections, transplant-related complications and ability to eat were compared between infants with early (Group 1, n = 13) and late (Group 2, n = 10) nephrectomy. 'Early' was defined as nephrectomy at 7-kg body weight followed by peritoneal dialysis and 'late' as nephrectomy at ≥10 kg followed by 3-4 weeks of haemodialysis and kidney transplantation. Patients were followed until the end of the first post-transplant year.

RESULTS

Dialysis time was significantly longer in group 1 than in group 2. Late nephrectomy did not increase the risk for thromboembolic events or septicaemia but decreased tube feeding dependency (group 1 69% vs. group 2 20%, p = 0.019). Motor development at transplantation was considered normal in 80% of the infants with late nephrectomy compared to 31% in the early nephrectomy group (p = 0.019); however, the difference between the groups disappeared by the end of the follow-up.

CONCLUSION

Infants with late nephrectomy have comparative outcome but less feeding tube dependency and better motor development during the first post-transplant months compared to infants with early nephrectomy.

Changes in graft outcomes in recipients <10 kg over 25 years of pediatric kidney transplantation in the United States

BACKGROUND

Kidney transplant (KT) was initially associated with poor outcomes, especially in smaller recipients. However, pediatric transplantation has evolved considerably over time. We investigated the impact of weight at the time of transplant and whether outcomes changed over 25 years for <10 kg recipients.

METHODS

Using the UNOS database, pediatric recipient outcomes were analyzed between 1/1/99 and 12/31/14. KT weight was stratified: <8.6 kg (mean weight of recipients <10 kg), 8.6-9.9 kg, 10-14.9 kg, 15-29.9 kg, and ≥30 kg. Outcomes in recipients <10 kg were then compared between 1990-1999 and 2000-2014.

RESULTS

17 314 pediatric KT recipients were included; 518 (3%) had a transplant weight <10 kg. The highest rates of allograft loss and death were in recipients <8.6 kg and ≥30 kg. Recipients <8.6 kg also had higher rates of delayed graft function, rejection, and longer hospital length of stay. In the multivariable Cox regression model, transplant weight was not a predictor of allograft loss. When compared with recipients <8.6 kg, patient survival hazard ratios associated with recipient weight of 10-14.9 kg, 15-29.9 kg, and ≥30 kg were 0.61 (95%CI: 0.4, 1), 0.42 (95%CI: 0.3, 0.7) and 0.32 (95%CI: 0.2, 0.6), respectively. In the later era of transplant, recipients <10 kg had improved outcomes on univariate analysis; however, the era of transplantation was not an independent predictor of allograft loss or patient survival in Cox regression models.

CONCLUSIONS

Outcomes in children weighing 8.6-9.9 kg at the time of KT were similar to higher weight groups and improved over time; however, special precautions should be taken for recipients <8.6 kg at the time of transplant.

Predicting wait time for pediatric kidney transplant: a novel index

BACKGROUND

Over one thousand pediatric kidney transplant candidates are added to the waitlist annually, yet the prospective time spent waiting is unknown for many. Our study fills this gap by identifying variables that impact waitlist time and by creating an index to predict the likelihood of a pediatric candidate receiving a transplant within 1 year of listing. This index could be used to guide patient management by giving clinicians a potential timeline for each candidate's listing based on a unique combination of risk factors.

METHODS

A retrospective analysis of 3757 pediatric kidney transplant candidates from the 2014 to 2020 OPTN/UNOS database was performed. The data was randomly divided into a training set, comprising two-thirds of the data, and a testing set, comprising one-third of the data. From the training set, univariable and multivariable logistic regressions were used to identify significant predictive factors affecting wait times. A predictive index was created using variables significant in the multivariable analysis. The index's ability to predict likelihood of transplantation within 1 year of listing was validated using ROC analysis on the training set. Validation of the index using ROC analysis was repeated on the testing set.

RESULTS

A total of 10 variables were found to be significant. The five most significant variables include the following: blood group, B (OR 0.65); dialysis status (OR 3.67); kidney disease etiology, SLE (OR 0.38); and OPTN region, 5 (OR 0.54) and 6 (OR 0.46). ROC analysis of the index on the training set yielded a c-statistic of 0.71. ROC analysis of the index on the testing set yielded a c-statistic of 0.68.

CONCLUSIONS

This index is a modest prognostic model to assess time to pediatric kidney transplantation. It is intended as a supplementary tool to guide patient management by providing clinicians with an individualized prospective timeline for each candidate. Early identification of candidates with potential for prolonged waiting times may help encourage more living donation including paired donation chains.

Analysis of Factors Related to the Success of Pediatric Kidney Transplantation: A 35 Years Experience

BACKGROUND

Despite the significant improvement results over the past 20 years, pediatric kidney transplantation remains a challenge. Chronic rejection, thrombosis, and recurrence of the primary disease are frequent causes of graft loss that have been little studied. Therefore, our objective is to analyze factors related to a better prognosis, which can be used to improve future strategies to allow higher pediatric transplant success rates.

METHODS

A retrospective cohort study with patients under 15 years old submitted for kidney transplantation at the Hospital das Clínicas da UNICAMP between January 1, 1987, and January 1, 2022. Age, patient weight, time and type of dialysis, use of anticoagulation, complications, ischemia time, and donor weight were analyzed and related to graft loss. The significance level adopted for the statistical tests was 5%.

RESULTS

One hundred ninety-two medical records were anaThe mean follow-up time was 11 years, and the mean graft duration was ration 8.5 years. The main causes of graft loss were chronic dysfunction, thrombosis, and acute cellular rejection. Thrombosis presented significantly with the donor's body mass index and second transplantation. There was no correlation between the analyzed variables and chronic dysfunction or acute cellular rejection.

DISCUSSION

Thrombosis remains the main cause of early graft loss, followed by acute cellular rejection. Measures such as thrombophilia screening and thromboprophylaxis have been proposed to improve results. However, they are still not standardized.

CONCLUSION

The main causes of graft loss were chronic dysfunction, thrombosis, and acute cellular rejection. Only the thrombosis was related to the donor's body mass index and a second transplantation.

Pediatric kidney transplantation: outcomes with under and over 6-year-old donors

OBJECTIVE

Kidney shortage for pediatric kidney transplantation (PKT) entails the need to use low-weight and age donors, despite the apprehension. The aim of this study was to analyze the pediatric deceased donor kidney transplantations (pDDKT) outcomes in the first year after the procedure, stratified by donor age.

METHOD

Retrospective cohort of pDDKTs carried out between January 2013, and January 2018, at a PKT reference hospital in Southern Brazil. Donors were divided into group 1 (≤ 6 years), and group 2 (> 6 years); the analysis of the outcomes was carried out in the same period.

RESULTS

There were 143 pDDKTs; 51 (35.66%) in group 1; and 92 (64.34%) in group 2. In both groups there were 17 graft losses (11.8%), with vascular thrombosis as the main cause (group 1: 5; group 2: 4). Among the complications, renal artery stenosis (RAS) with indication for angioplasty and stenting was more frequent in group 1 (7.8%; group 2: 2.2%). The 1-year Renal Transplant Recipients' and graft survival did not show significant differences between the groups, (p =  = 0.95). However, the Glomerular Filtration Rate analysis was higher in group 2, reaching, in the 12th month, 79.3 mL/min/1,73m2, compared to 69.7 mL/min/1,73m2 in group 1(p =  = 0.033).

CONCLUSIONS

Small donors can be considered for pDDKTs, as long as there is an expert team to perform the transplantation.

Associations of longitudinal height and weight with clinical outcomes in pediatric kidney replacement therapy: results from the ESPN/ERA Registry

BACKGROUND

Associations between anthropometric measures and patient outcomes in children are inconsistent and mainly based on data at kidney replacement therapy (KRT) initiation. We studied associations of height and body mass index (BMI) with access to kidney transplantation, graft failure, and death during childhood KRT.

METHODS

We included patients < 20 years starting KRT in 33 European countries from 1995-2019 with height and weight data recorded to the ESPN/ERA Registry. We defined short stature as height standard deviation scores (SDS) < -1.88 and tall stature as height SDS > 1.88. Underweight, overweight and obesity were calculated using age and sex-specific BMI for height-age criteria. Associations with outcomes were assessed using multivariable Cox models with time-dependent covariates.

RESULTS

We included 11,873 patients. Likelihood of transplantation was lower for short (aHR: 0.82, 95% CI: 0.78-0.86), tall (aHR: 0.65, 95% CI: 0.56-0.75), and underweight patients (aHR: 0.79, 95%CI: 0.71-0.87). Compared with normal height, patients with short and tall statures showed higher graft failure risk. All-cause mortality risk was higher in short (aHR: 2.30, 95% CI: 1.92-2.74), but not in tall stature. Underweight (aHR: 1.76, 95% CI: 1.38-2.23) and obese (aHR: 1.49, 95% CI: 1.11-1.99) patients showed higher all-cause mortality risk than normal weight subjects.

CONCLUSIONS

Short and tall stature and being underweight were associated with a lower likelihood of receiving a kidney allograft. Mortality risk was higher among pediatric KRT patients with a short stature or those being underweight or obese. Our results highlight the need for careful nutritional management and multidisciplinary approach for these patients. A higher resolution version of the Graphical abstract is available as Supplementary information.

Long-term mortality in pediatric solid organ recipients-A nationwide study

BACKGROUND

The present study aimed at investigating long-term mortality of patients who underwent solid organ transplantation during childhood and at identifying their causes of death.

METHODS

A cohort of 233 pediatric solid organ transplant recipients who had a kidney, liver, or heart transplantation between 1982 and 2015 in Finland were studied. Year of birth-, sex-, and hometown-matched controls (n = 1157) were identified using the Population Register Center registry. The Causes of Death Registry was utilized to identify the causes of death.

RESULTS

Among the transplant recipients, there were 60 (25.8%) deaths (median follow-up 18.0 years, interquartile range of 11.0-23.0 years). Transplant recipients' risk of death was nearly 130-fold higher than that of the controls (95% CI 51.9-1784.6). The 20-year survival rates for kidney, liver, and heart recipients were 86.1% (95% CI 79.9%-92.3%), 58.5% (95% CI 46.2%-74.1%), and 61.4% (95% CI 48.1%-78.4%), respectively. The most common causes of death were cardiovascular diseases (23%), infections (22%), and malignancies (17%). There were no significant differences in survival based on sex or transplantation era.

CONCLUSION

The late mortality is still significantly higher among pediatric solid organ recipients in comparison with controls. Cardiovascular complications, infections, and cancers are the main causes of late mortality for all studied transplant groups. These findings emphasize the cruciality of careful monitoring of pediatric transplant recipients in order to reduce long-term mortality.

Oral findings in kidney transplant children and adolescents

BACKGROUND

Children and adolescents undergoing kidney transplantation may present oral conditions after the procedure, but a few studies have recently described them.

AIM

To describe the oral conditions of post-renal transplant children and adolescents.

DESIGN

Two calibrated dentists examined all the participants by assessing caries experience, enamel defects, periodontal condition and soft tissue lesions.

RESULTS

A total of 120 participants were included in the study, in which 63 (52.5%) were male and 57 (47.5%) were female, with a mean age of 12.78 ± 3.9 years. Among the participants, 104 (86.7%) showed at least one oral change directly related to kidney disease. The most frequent oral findings were enamel defect (49/120; 40.8%) and drug-induced gingival overgrowth (DIGO) (20/120; 16.7%). Gingival bleeding was observed on probing in 115 (95.8%) participants, whereas 69 (57.5%) presented dental calculus and 51 (42.5%) had caries experience.

CONCLUSION

Gingival bleeding, enamel defects and DIGO were the most frequent oral findings in kidney transplant children and adolescents. The use of amlodipine and anticonvulsants was associated with DIGO, and there was a positive correlation between oral ulcers and use of everolimus.

Overview of pediatric kidney transplantation

Kidney transplantation is the treatment of choice for pediatric patients with end-stage kidney disease. Unlike adult recipients undergoing transplantation, special considerations must be taken when transplanting children based on the underlying etiology of kidney disease, previous surgical procedures, anatomical limitations and necessary technical adjustments. Additionally, the choice of donor must be measured to ensure optimal graft survival given a longer post-transplant life expectancy. Those topics as well as frequently encountered postoperative complications are also discussed in this publication.

Anesthetic considerations for pediatric abdominal solid organ transplantation

While many pediatric patients undergo abdominal solid organ transplants every year worldwide, each is unique due to varying age, size, and comorbidities; thus, they require a careful anesthesia plan to undergo surgery safely. This article reviews the anesthetic considerations and management of patients undergoing liver and kidney transplantation. Preoperative, intraoperative, and post-operative management are discussed, including induction, access, monitoring, and maintenance. Blood transfusion is also addressed.

Kidney Transplantation in Small Children: Association Between Body Weight and Outcome-A Report From the ESPN/ERA-EDTA Registry

BACKGROUND

Many centers accept a minimum body weight of 10 kg as threshold for kidney transplantation (Tx) in children. As solid evidence for clinical outcomes in multinational studies is lacking, we evaluated practices and outcomes in European children weighing below 10 kg at Tx.

METHODS

Data were obtained from the European Society of Paediatric Nephrology/European Renal Association and European Dialysis and Transplant Association Registry on all children who started kidney replacement therapy at <2.5 y of age and received a Tx between 2000 and 2016. Weight at Tx was categorized (<10 versus ≥10 kg) and Cox regression analysis was used to evaluate its association with graft survival.

RESULTS

One hundred of the 601 children received a Tx below a weight of 10 kg during the study period. Primary renal disease groups were equal, but Tx <10 kg patients had lower pre-Tx weight gain per year (0.2 versus 2.1 kg; P < 0.001) and had a higher preemptive Tx rate (23% versus 7%; P < 0.001). No differences were found for posttransplant estimated glomerular filtration rates trajectories (P = 0.23). The graft failure risk was higher in Tx <10 kg patients at 1 y (graft survival: 90% versus 95%; hazard ratio, 3.84; 95% confidence interval, 1.24-11.84), but not at 5 y (hazard ratio, 1.71; 95% confidence interval, 0.68-4.30).

CONCLUSIONS

Despite a lower 1-y graft survival rate, graft function, and survival at 5 y were identical in Tx <10 kg patients when compared with Tx ≥10 kg patients. Our results suggest that early transplantation should be offered to a carefully selected group of patients weighing <10 kg.

Surgical considerations in paediatric kidney transplantation: an update

Background

Kidney transplantation has established itself as the most appropriate mode of renal replacement therapy for the majority with end-stage kidney disease. Although at present this is applicable for children as well as adults, a few decades back kidney transplantation was not considered a first-line option in children. This was due to inferior outcomes following transplantation in this age group compared to that of adults. These poor results were attributed to challenges in paediatric transplantation such as the shortage of suitable donors, technical difficulties in performing a sound vascular anastomosis and the adverse effects of immunosuppressive medication on growth and development. However, current patient and graft-centred outcomes after paediatric transplantation equal or surpass that of adults. The advances in evaluation and management of specific surgical concerns in children who undergo transplantation, such as pre-transplant native nephrectomy, correction of congenital anomalies of the urinary tract, placement of an adult-sized kidney in a small child and minimizing the risk of allograft thrombosis, have contributed immensely for these remarkable outcomes.

Conclusions

In this review, we aim to discuss surgical factors that can be considered unique for children undergoing kidney transplantation. We believe that an updated knowledge on these issues will be invaluable for transplant clinicians, who are dealing with paediatric kidney transplantation.

Long-term outcomes of living-donor kidney transplant children weighing less than 15 kg: Comparison of the surgical approach

INTRODUCTION

Kidney transplantation (KTx) is the most effective treatment for end-stage renal disease in children.

OBJECTIVES

We aimed to compare the long-term outcomes and surgical complications of the intraperitoneal approach (IPA) and extraperitoneal approach (EPA) for KTx in children weighing <15 kg.

STUDY DESIGN

We performed a retrospective cohort study on pediatric kidney transplant recipients, weighing <15 kg, who received their first living-related kidney transplant between January 1987 and December 2015. Patients were divided into two groups based on the surgical approach (IPA or EPA) during transplant, and clinical data were extracted from the medical records.

RESULTS

The median follow-up duration was 14.1 years (interquartile range, 9.0-19.2). Comparing the two groups (IPA group, n = 62; EPA group, n = 38), the median age and body weight were significantly lower in the IPA group (4.2 vs. 4.8 years, P = 0.03; 11.7 vs. 13.0 kg, P < 0.01). There were 26 surgical complications (26%) in 19 patients during the follow-up period. The surgical complication rate was higher in the IPA group (39% vs. 6%).

DISCUSSION

We assessed the long-term outcomes of the surgical approaches used for pediatric patients weighing <15 kg who underwent KTx and received a size-mismatched adult donor kidney. There was no significant difference in renal transplantation prognosis using the surgical approach, but IPA-related complications were more frequent in the long term. Therefore, our data suggest that in cases of donor-recipient size mismatch in pediatric KTx, the EPA, associated with fewer surgical complications, is preferable to the IPA if the patient's body size has sufficient space for allograft placement.

CONCLUSION

The transplant approach did not influence the long-term outcomes in children weighing <15 kg, but EPA had fewer surgical complications and was technically safe.

Expression of fibrosis-related genes in liver allografts: Association with histology and long-term outcome after pediatric liver transplantation

BACKGROUND

Unexplained graft fibrosis and inflammation are common after pediatric liver transplantation (LT).

OBJECTIVE

We investigated the graft expression of fibrogenic genes and correlated the findings with transplant histopathology and outcome.

METHODS

Liver biopsies from 29 recipients were obtained at a median of 13.1 (IQR: 5.0-18.4) years after pediatric LT. Control samples were from six liver-healthy subjects. Hepatic expression of 40 fibrosis-related genes was correlated to histological findings: normal histology, fibrosis with no inflammation, and fibrosis with inflammation. Liver function was evaluated after a subsequent follow-up of 9.0 years (IQR: 8.0-9.4).

RESULTS

Patients with fibrosis and no inflammation had significantly increased gene expression of profibrotic TGF-β3 (1.17 vs. 1.02 p = .005), CTGF (1.64 vs. 0.66 p = .014), PDGF-α (1.79 vs. 0.98 p = .049), PDGF -β (0.99 vs. 0.76 p = .006), integrin-subunit-β1 (1.19 vs. 1.02 p = .045), α-SMA (1.12 vs. 0.58 p = .013), type I collagen (0.82 vs. 0.53 p = .005) and antifibrotic decorin (1.15 vs. 0.99 p = .045) compared to patients with normal histology. mRNA expression of VEGF A (0.84 vs. 1.06 p = .049) was lower. Only a few of the studied genes were upregulated in patients with both fibrosis and inflammation. The gene expression levels showed no association with later graft outcome.

CONCLUSIONS

Altered hepatic expression of fibrosis-related genes is associated with graft fibrosis without concurrent inflammation.

Surgical complications in pediatric kidney transplantation-Incidence, risk factors, and effects on graft survival: A retrospective single-center study

The field of pediatric kidney transplantation remains challenging due to an ongoing lack of size-matched grafts and anatomical peculiarities. In the current study, we investigated the incidence of surgical complications in pediatric recipients, with a focus on risk factors and effects on graft outcome. We retrospectively reviewed all 2386 kidney transplantations at our institution from January 2005 until December 2018. Of these, 221 transplants were performed in pediatric recipients, defined as under the age of 18 years. Donor-recipient body surface area ratios were calculated to evaluate the effects of size mismatching. Regression analyses were performed to identify independent risk factors for surgical complications and graft survival, respectively. Perioperative surgical complications requiring revision were observed in 34 (15.4%) cases. Leading cause for revision were vascular complications such as thrombosis or stenosis (n = 15 [6.8%]), which were significantly more frequent in case of young donors, (ie, donor age <6 years; OR: 4.281; CI-95%:1.385-13.226; P = .012), previous nephrectomy (OR: 3.407; CI-95%:1.019-11.387; P = .046), and en-bloc grafts (OR: 4.923; CI-95%:1.355-17.884; P = .015), followed by postoperative hemorrhage (n = 10 [4.5%]), ureteral complications (n = 8 [3.6%]), and lymphoceles (n = 7 [3.2%]). Median follow-up was 84.13 (0.92-175.72) months. One-, 5-, and 10-year graft survival rates were 97.1%, 88.9%, and 65.1%, respectively. Except for vascular complications (HR: 4.727; CI-95%:1.363-16.394; P = .014), none of the analyzed surgical morbidities significantly influenced graft survival. In conclusion, pediatric kidney transplantation achieves excellent long-term results. However, meticulous surgical technique and continuous postoperative monitoring are imperative for early detection and treatment of imminent vascular complications, especially in case of young donors and en-bloc grafts.

Donor considerations in pediatric kidney transplantation

This article reviews kidney transplant donor options for children with end-stage kidney disease (ESKD). Global access to kidney transplantation is variable. Well-established national policies, organizations for organ procurement and allocation, and donor management policies may account for higher deceased donor (DD transplants) in some countries. Living donor kidney transplantation (LD) predominates in countries where organ donation has limited national priority. In addition, social, cultural, religious and medical factors play a major role in both LD and DD kidney transplant donation. Most children with ESKD receive adult-sized kidneys. The transplanted kidney has a finite survival and the expectation is that children who require renal replacement therapy from early childhood will probably have 2 or 3 kidney transplants in their lifetime. LD transplant provides better long-term graft survival and is a better option for children. When a living related donor is incompatible with the intended recipient, paired kidney exchange with a compatible unrelated donor may be considered. When the choice is a DD kidney, the decision-making process in accepting a donor offer requires careful consideration of donor history, kidney donor profile index, HLA matching, cold ischemia time, and recipient's time on the waiting list. Accepting or declining a DD offer in a timely manner can be challenging when there are undesirable facts in the donor's history which need to be balanced against prolonging dialysis in a child. An ongoing global challenge is the significant gap between organ supply and demand, which has increased the need to improve organ preservation techniques and awareness for organ donation.

Intravesical monitoring of intra-abdominal pressure after renal transplantation in children: A safety and feasibility study

IAH after RTX can threaten graft viability. This study aimed to assess the feasibility and safety of longitudinal IAP measurements as an IAH screening method in children after RTX. A cohort of eight children with a mean ± SD [range] age 9.6 ± 6.2 [2-17] years who underwent RTX and 18 control patients were evaluated between May 2017 and February 2018. We compared longitudinal IAP measurements using a Foley manometer to other clinical monitoring data. In total, 29 IAP measurements were performed in RTX patients and 121 in controls. The mean post-operative IAP was 7.4 ± 4.3 [1-16] mm Hg following RTX and 8.1 ± 3.7 [1-19] mm Hg in controls. We noted IAH in 9 (31%) of 29 IAP measurements after RTX and in 41 (34%) of 121 IAP measurements in controls. No graft dysfunction occurred in RTX patients despite elevated IAP values. The mean ± SD [range] time expenditure for IAP measurement was 2.1 ± 0.4 [0.6-3.2] minutes. No severe complications occurred during the IAP measurements. Analysis of longitudinal IAP measurements demonstrated that IAP measurement is safe and feasible in children recovering from renal transplantation in the PICU.

Strategy to Enable and Accelerate Kidney Transplant in Small Children and Results of the First 130 Transplants in Children ≤15 kg in a Single Center

BACKGROUND

Proper care of young children in need of kidney transplant (KT) requires many skilled professionals and an expensive hospital structure. Small children have lesser access to KT.

METHODS

We describe a strategy performed in Brazil to enable and accelerate KT in children ≤15 kg based on the establishment of one specialized transplant center, focused on small children, and cooperating with distant centers throughout the country. Actions on 3 fronts were implemented: (a) providing excellent medical assistance, (b) coordinating educational activities to disseminate expertise and establish a professional network, and (c) fostering research to promote scientific knowledge. We presented the number and outcomes of small children KT as a result of this strategy.

RESULTS

Three hundred forty-six pediatric KTs were performed in the specialized center from 2009 to 2017, being 130 in children ≤15 kg (38%, being 41 children ≤10 kg) and 216 in >15 kg (62%). Patient survival after 1 and 5 years of the transplant was 97% and 95% in the "small children" group, whereas, in the "heavier children" group, it was 99% and 96% (P = 0.923). Regarding graft survival, we observed in the "small children" group, 91% and 87%, whereas in the "heavier children" group, 94% and 87% (P = 0.873). These results are comparable to the literature data. Groups were similar in the incidence of reoperation, vascular thrombosis, posttransplant lymphoproliferative disease, and estimated glomerular filtration rate.

CONCLUSIONS

The strategy allowed an improvement in the number of KT in small children with excellent results. We believe this experience may be useful in other locations.

Hemodialysis Catheters in Infants: A Retrospective Single-Center Cohort Study

PURPOSE

Evaluate technical aspects and outcomes of insertion/maintenance of hemodialysis (HD) central venous catheter (CVC) during infancy.

MATERIALS AND METHODS

Single-center retrospective study of 29 infants who underwent 49 HD-CVC insertions between 2002 and 2016. Demographics, procedural, and post-procedural details, interventional radiology (IR) maintenance procedures, technical modifications, complications, and outcomes were evaluated. Technical adjustments during HD-CVC placement to adapt catheter length to patient size were labeled "modifications." CVCs requiring return visit to IR were called IR-maintenance procedures. Mean age and weight at HD-CVC insertion were 117 days and 4.9 kg.

RESULTS

Of the 29 patients, 13 (45%) required renal-replacement-therapy (RRT) as neonates, 10 (34%) commenced RRT with peritoneal dialysis (PD), and 19 (66%) with HD. Fifteen nontunneled and 34 tunneled HD-CVCs were inserted while patients were ≤1 year. Technical modifications were required placing 25/49 (51%) HD-CVCs: 5/15 (33%) nontunneled and 20/34 (59%) tunneled catheters (P = .08). Patients underwent ≤6 dialysis-cycles/patient during infancy (mean 2.3), and a mean of 4.1 and 49 HD-sessions/catheter for nontunneled and tunneled HD-CVCs, respectively. Mean primary and secondary device service, and total access site intervals for tunneled HD-CVCs were 75, 115, and 201 days, respectively. A total of 26 of 49 (53%) patients required IR-maintenance procedures. Nontunneled lines had greater catheter-related bloodstream infections per 1,000 catheter-days than tunneled HD-CVCs (9.25 vs. 0.85/1,000 catheter days; P = .02). Nineteen patients (65%) survived over 1 year. At final evaluation (December 2017): 8/19 survived transplantation, 5/19 remained on RRT, 2/19 completely recovered, 1/19 lost to follow-up, and 3 died at 1.3, 2, and 10 years.

CONCLUSIONS

Placement/maintenance of HD-CVCs in infants pose specific challenges, requiring insertion modifications, and IR-maintenance procedures to maintain function.

Congenital nephrotic syndrome: is early aggressive treatment needed? Yes

Congenital nephrotic syndrome (CNS) was primarily considered one disease entity. Hence, one treatment protocol was proposed in the beginning to all CNS patients. Today, with the help of gene diagnostics, we know that CNS is a heterogeneous group of disorders and therefore, different treatment protocols are needed. The most important gene defects causing CNS are NPHS1, NPHS2, WT1, LAMB2, and PLCE1. Before active treatment, all infants with CNS died. It was stated already in the mid-1980s that intensive medical therapy followed by kidney transplantation (KTx) should be the choice of treatment for infants with severe CNS. In Finland, early aggressive treatment protocol was adopted from the USA and further developed for treatment of children with the Finnish type of CNS. The aim of this review is to state reasons for "early aggressive treatment" including daily albumin infusions, intensified nutrition, and timely bilateral nephrectomy followed by KTx at the age of 1-2 years.

Perioperative renal transplantation management in small children using adult-sized living or deceased donor kidneys: A single-center experience

Kidney transplantation remains the treatment of choice for children with ESRD. Optimal perioperative management is critical in small recipients of ASK to assure adequate graft perfusion. We present a single-center experience outlining management for patients weighing <20 kg who underwent primary renal transplantation with ASKs between 2007 and 2016. Sixty-three patients met study criteria and underwent 34 living-related, six living-unrelated, and 23 deceased donor kidney transplants. Median age and weight at transplant were 25 months (IQR 18-37 months; range 11 months-6 years) and 11.0 kg (IQR 9.2-14.5 kg; range 7.1-19.5 kg). Eighty-nine percent of patients required vasoactive agents intra-operatively, with twenty patients requiring prolonged vasoactive agents post-operatively. Intra-operatively, patients received 51.9 mL/kg of crystalloid, 27.3 mL/kg of 5% albumin, and 13.6 mL/kg of packed red blood cells. Most (93.7%) patients were extubated on POD#0. Weights peaked on post-operative days three through five. Over a median follow-up of 49 months (IQR 31-86 months; range 0-130 months), four grafts were lost, two due to thrombosis and two secondary to chronic rejection. There was one patient death six months post-transplant due to causes unrelated to transplantation. Graft survival at 1, 5, and 10 years was 98.4%, 96.6%, and 84.2%, respectively. Of surviving allografts, the median 1, 5, and 10 years post-transplant eGFR was 122.9, 90.0, and 59.2 mL/min/1.73 m² as determined by the 2009 Schwartz formula. Renal transplantation in small children using ASKs requires meticulous perioperative management including adequate fluid resuscitation and judicious use of pressors to assure adequate graft perfusion. The use of ASKs from living or deceased donors results in satisfactory short and long-term outcomes.

Good long-term renal graft survival and low incidence of cardiac pathology in adults after short dialysis period and renal transplantation in early childhood - a cohort study

Over the past 30 years, there has been an improvement in both patient and graft survival after pediatric renal transplantation (RTX). Despite this success, these patients still carry an elevated risk for untimely death, partly through premature aging of the vasculature. The aim of this study was thus to investigate the long-term outcome of individuals with RTX in childhood, as well as to explore the cardiovascular health of these adults more than a decade later. We studied 131 individuals who had undergone a RTX between the years 1979 and 2005. Furthermore, left ventricular hypertrophy (LVH), coronary artery calcifications (CAC), and related metabolic factors were investigated in a cross-sectional study including 52 individuals as part of the initial cohort. The mortality rate (n = 131) was 12.2%. The median estimated graft survival was 17.5 years (95% CI 13.6-21.3), being significantly better in children transplanted below the age of 5 years (18.6 vs. 14.3 years, P < 0.01) compared with older ones. CAC were found in 9.8% and LVH in 13% of the patients. Those with cardiac calcifications had longer dialysis vintage and higher values of parathyroid hormone (PTH) during dialysis. Left ventricular mass correlated positively with systolic blood pressure, PTH, and phosphate measured at the time of the study.

Is Preoperative Preparation Time a Barrier to Small Children Being Ready for Kidney Transplantation?

BACKGROUND

Small children are less frequently transplanted when compared with older. The objective of the present study was to compare the preparation time for transplantation in children of different weights and to identify factors associated with a delay in the workup of small children.

METHODS

We report on a retrospective cohort comprising all children referred for renal transplantation (RTx) workup between 2009 and 2017. The main outcome was transplantation workup time, defined as the time elapsed between the first consultation and when the child became ready for the surgery.

RESULTS

A total of 389 children (63.5% males) were selected, with a median weight of 18 kg (interquartile range, 11-32). Patients were categorized into 2 groups: group A (study group): ≤15 kg (n = 165) and group B (control group): >15 kg (n = 224). The probability of being ready for RTx was comparable between groups A and B. The cumulative incidence rate difference between groups is -0.05 (95% confidence interval, -0.03 to 0.02). The median time for RTx workup was 5.4 (2.4-9.4) in group A and 4.3 (2.2-9.0) months in group B (P = 0.451). Moreover, the presence of urinary tract malformation was associated with the need for longer transplantation workup time (P < 0.001).

CONCLUSIONS

In children >7 kg, the workup time for transplantation is not related to body weight. In a specialized center, children weighing 7-15 kg became ready within the same timeframe as children weighing >15 kg, despite the smaller children had greater difficulty being nourished, dialyzed, and a greater need for surgical correction of the urinary tract pretransplant.

Development of a risk score for earlier diagnosis of chronic kidney disease in children

Objective

To develop a clinical score for the early identification of chronic kidney disease (CKD) in children and adolescents. The early diagnosis of CKD in childhood allows the adoption of measures to slow the progression of the disease, thereby reducing morbidity and mortality. Nevertheless, the diagnosis is often made too late for proper patient management.

Study design

We preformed a case-control study of a multicenter Brazilian sample of 752 pediatric patients; the study cases (n = 376) were CKD patients with a median estimated GFR of 37 (IQR = 22 to 57) ml/min/1.73 m². The control group (n = 376) comprised age-, gender- and center-matched children who were followed for nonrenal diseases. Potential risk factors were investigated through a standard questionnaire that included symptoms, medical history, and a clinical examination. Two multivariable models (A and B) were fitted to assess predictors of the diagnosis of CKD.

Results

In model A, 9 variables were associated with CKD diagnosis: antenatal ultrasound with urinary malformation, recurrent urinary tract infection, polyuria, abnormal urine stream, nocturia, growth curve flattening, history of hypertension, foamy urine and edema (c-statistic = 0.938). Model B had the same variables as model A, except for the addition of the history of admission during the neonatal period and the exclusion of antenatal ultrasound variables (c-statistic = 0.927).

Conclusions

The present scores may serve as a warning sign for CKD diagnosis in children among professionals working in the primary care setting where the symptoms associated with a risk of CKD may be overlooked.

Amnioinfusions to Treat Early Onset Anhydramnios Caused by Renal Anomalies: Background and Rationale for the Renal Anhydramnios Fetal Therapy Trial

Anhydramnios caused by early anuria is thought to be universally fatal due to pulmonary hypoplasia. Bilateral renal agenesis and early fetal renal failure leading to anhydramnios constitute early pregnancy renal anhydramnios (EPRA). There have been successful reports of amnioinfusions to promote lung growth in the setting of EPRA. Some of these successfully treated EPRA fetuses have survived the neonatal period, undergone successful dialysis, and subsequently received a kidney transplant. Conversely, there are no reports of untreated EPRA survivors. This early success of amnioinfusions to treat EPRA justifies a rigorous prospective trial. The objective of this study is to provide a review of what is known about fetal therapy for EPRA and describe the Renal Anhydramnios Fetal Therapy trial. We review the epidemiology, pathophysiology, and genetics of EPRA. Furthermore, we have performed systematic review of case reports of treated EPRA. We describe the ethical framework, logistical challenges, and rationale for the current single center (NCT03101891) and planned multicenter trial.

Clinical implication of renal allograft volume to recipient body surface area ratio in pediatric renal transplant

Our study aims to assess the clinical implication of RAV/rBSA ratio in PRT as a predictor for attained renal function at 1 year post-transplantation and its association with surgical complications. A retrospective cohort was performed for PRT cases from January 2000 to December 2015 in our institution. Extracted clinical information includes the recipient's demographics, donor type, renal allograft characteristics, arterial, venous and ureteral anastomoses, vascular anastomosis time while kidney off ice, overall operative time, and estimated blood loss. The RAV/rBSA was extrapolated and assessed for its association with renal graft function attained in 1 year post-transplantation and surgical complications within 30-day post-transplantation. A total of 324 PRTs cases were analyzed. The cohort consisted of 187 (52.4%) male and 137 (42.3%) female recipients, with 152 (46.9%) living donor and 172 (53.1%) deceased donor renal transplants, and an overall median age of 155.26 months (IQR 76.70-186.98) at time of renal transplantation. The receiver operating characteristic identified that a RAV/rBSA ratio of 135 was the optimal cutoff in determining the renal graft function outcome. Univariate and multivariate analyses revealed the relative OR for RAV/rBSA ≥ 135 ratio in predicting an eGFR ≥ 90 attained within 1 year post-transplant was highest among younger pediatric recipients (<142.5 months) of deceased kidney donors (OR = 11.143, 95% CI = 3.156-39.34). Conversely, Kaplan-Meier analysis revealed that RAV/rBSA ratio ≥ 135 is associated with lower odds of having eGFR <60 (OR = 0.417, 95% CI = 0.203-0.856). The RAV/rBSA ratio was not associated nor predictive of transplant-related surgical complications. Our study determined that the RAV/rBSA ratio is predictive of renal graft function at 1-year PRT, but not associated with any increased surgical complications.

Increased risk organ transplantation in the pediatric population

IRD organs are classified by the Public Health Service to be at above-average risk for harboring human immunodeficiency virus, hepatitis C, and hepatitis B. Traditionally underutilized, there exists even greater reluctance for their use in pediatric patients. We performed a retrospective analysis via the United Network for Organ Sharing database of all pediatric renal and hepatic transplants performed from 2004 to 2008 in the United States. Primary outcomes were patient and graft survival. Proportional hazards regression was performed to control for potentially confounding factors. Waitlist time, organ acceptance rates, and infectious transmissions were analyzed. There were 1830 SRD renal, 92 IRD renal, 1695 SRD hepatic, and 59 IRD hepatic transplants. There were no statistically significant differences in allograft or patient survival in either group. Acceptance rates of IRD organs were lower for kidney (1.5% IRD vs 4.82% SRD) and liver (1.99% IRD vs 4.51% SRD). One transmission of a bloodborne pathogen involving a pediatric recipient out of 7797 unique transplants was reported from 2008 to 2015. IRD organs appear to have equivalent outcomes. Increasing their utilization may improve access to transplant while decreasing wait times and circumventing waitlist morbidity and mortality.

Special Considerations in Pediatric Kidney Transplantation

Universally accepted as the treatment of choice for children needing renal replacement therapy, kidney transplantation affords children the opportunity for an improved quality of life over dialysis therapy. Immunologic and surgical advances over the last 15 years have improved the pediatric patient and kidney graft survival. Unique to pediatrics, congenital genitourinary anomalies are the most common primary diseases leading to kidney failure, many with urological issues. Early urological evaluation for post-transplant bladder dysfunction and emphasis on immunization adherence are the mainstays of pediatric pretransplant and post-transplant evaluations. A child's height can be challenging, sometimes requiring an intra-abdominally placed graft, particularly if the patient is <20 kg. Maintenance immunosuppression regimens are similar to adult kidney graft recipients, although distinctive pharmacokinetics may change dosing intervals in children from twice a day to thrice a day. Viral infections and secondary malignancies are problematic for children relative to adults. Current trends to reduce/remove corticosteroid therapy from post-transplant protocols have produced improved linear growth with less steroid toxicity; although these studies are still ongoing, graft function and survival are considered acceptable. Finally, all children with a kidney transplant need a smooth transition to adult clinics. Future research in pertinent psychosocial aspects and continued technological advances will only serve to optimize the transition process. Although some aspects of kidney transplantation are similar in children and adults, for instance immunosuppression and immunosuppressive regimens, and rejection mechanisms and their diagnosis using the Banff criteria, there are important differences this review will focus on and which continue to drive innovation.

Outcomes of pediatric living donor kidney transplantation: A single-center experience

Renal transplantation is the treatment of choice for children with ESRD offering advantages of improved survival, growth potential, cognitive development, and quality of life. The aim of our study was to compare the outcomes of LDKT vs DDKT performed in children at a single center. Retrospective chart review of pediatric patients who underwent kidney transplantation from 2005 to 2014 was performed. Ninety-one renal transplants were accomplished, and 31 cases (38.27%) were LDKT, and in 96.7% of the cases, the graft was obtained through laparoscopy. Thirty-four receptors weighted <25 kg. LDKT group had statistically significant lower cold ischemia times than DDKT one. Complication rate was 9.67% for LDKT and 18.33% for DDKT. eGFR was better in LDKT. Patient survival rate was 100% for LDKT and 98.3% for DDKT, and graft survival rate was 96.7% for LDKT and 88.33%-80% for DDKT at a year and 5 years. Our program of pediatric kidney transplantation has achieved optimal patient and graft survival rates with low rate of complications. Living donor pediatric kidney transplants have higher patient and better graft survival rates than deceased donor kidney transplants.