Kidney transplants for children under 1 year of age - a single-center experience

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.

Long-term outcomes of adult-size and size-matched kidney transplants in small pediatric recipients

INTRODUCTION

Adult-size kidneys are usually used for kidney transplantation in small pediatric recipients, but the influence of graft size in transplant outcome remains controversial. Our aim is to compare long-term transplant outcomes of using adult-size and size-matched kidneys in small pediatric recipients.

MATERIALS AND METHODS

Since 1999, 61 of 226 kidney transplants were achieved in recipients weighing <20 kg with 5 years of follow-up. Patients were analyzed according to the graft size received: (group-A) adult-size (n = 32), (group-B) size-matched (n = 29). Kidney size (KS), glomerular filtration rate (GFR) proteinuria and rejection were compared between groups at transplant time (T₀), at one (T₁), two (T₂), five years (T₅), and at the end of the follow-up (T_F) (median follow-up 8.47(0-17) years). Graft and patient survival were determined and compared between groups.

RESULTS

Mean KS was significantly different between groups at T₀ (A:11.3 ± 1.1 cm, B:8.8 ± 0.9 cm), (pT₀<0.01), group-B evidenced graft growth, reaching similar sizes to group-A at T₅ (A:11.7±1 cm, B:11.2±1 cm; pT₅ = 0.13) and T_F (A:12.2 ± 1.1 cm, B:12.4 ± 1.2 cm; pT_F = 0.63), and group-A had a slight graft growth at T_F (pT₀-T_F<0.01). Mean Schwartz-GFR at T₀ was greater in group-A (138 ± 33 ml/min/1.73 m²) than group-B (109 ± 34 mL/min/1.73 m²) (pT₀ = 0.01); during follow-up, it evidenced a reduction in group-A (T₅:90 ± 27, T_F:71 ± 24 mL/min/1.73 m²; pT₀-T₅<0.01; pT₀-T_F<0.01), meanwhile in group-B was stable until T₅ (104 ± 33 mL/min/1.73 m²; pT₀-T₅ = 0.54), declining at T_F (76 ± 31 mL/min/1.73 m²; pT₀-T_F<0.01); with no significant differences at T₁, T₂, T₅, and TF between groups. Similar results were observed in mean Filler-GFR of both groups (Figure). Proteinuria and episodes of rejection were no significantly different between groups during the follow-up (p > 0.01; p = 0.23). Graft and patient survival at 5 and 10 years did not show significant differences (p = 0.45; p = 0.10).

DISCUSSION

Despite the initial kidney size difference between groups, we have demonstrated that they tended to the same size during the follow-up. Adult-size kidneys presented a slight size increase in the long-term, suggesting that they have some growth potential in small recipients, in contrast to previous literature. Mean GFR between groups showed no significant differences in the long-term, suggesting that optimal graft perfusion and function can be achieved despite the size of the graft. We have demonstrated that there were no significant differences in long-term graft and patient survival; this results were similar to the most recent literature about this topic and different from the 90-2000s decades literature.

CONCLUSIONS

Adult-size kidneys may be transplanted to small recipients (<20 kg) with comparable outcomes to size-matched kidneys, with no significant differences in long-term KS, GFR, proteinuria, rejection, graft or patient survival.

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.

Outcome of kidney transplantation from young pediatric donors (aged less than 6 years) to young size-matched recipients

INTRODUCTION

Pediatric donation is underutilized because of presumed increased risk of vascular thrombosis (VT) and graft loss. Using young pediatric donors (YPDs) for young pediatric recipients (YPRs) is suggested to be even at greater risk and therefore precluded in many centers. The aim of this study was to analyze the outcome of kidney transplantation (KT) from YPD to age-matched YPR.

PATIENT AND METHODS

A retrospective study of 118 pediatric KT performed between January 2007-July 2017. The authors identified KT with YPD (considered as those aged <6 years) and age-matched YPR. Organ allocation was performed based on the best paired size (YPR for YPR). Data were collected regarding donor and recipient characteristics, surgical and urological complications, graft loss, and outcomes.

RESULTS

Forty cases of YPD to age-matched YPR were identified (33.89% of the cohort). Mean recipient and donor age were 2.9 years (SD 1.68) and 2.24 years (SD 1.5), respectively. Mean recipient and donor weight were 12.7 kg (SD 4.1) and 13.7 kg (SD 4.15), respectively. Thirty of those young recipients (75%) weighed <15 kg. The most frequent primary renal disease was the congenital nephrotic syndrome. Nine out of 40 patients (22.5%) had received a previous KT before. Three received a combined liver-KT. Eight (20%) were classified as high immunological risk and 19 (47.5%) as high thrombotic risk. All allografts were implanted extraperitoneally and anastomosed to the iliac vessels. Major complications requiring reintervention occurred in seven patients (17.5%): three VT, three bleeding episodes, and one ureteral necrosis. Remarkably, only one surgical complication (VT) resulted in graft loss. Regarding long-term urological complications, four patients (10%) all with obstructive uropathy-developed vesicoureteral reflux to the graft. Actuarial graft survival at 1,5, and 10 years in the YPD to age-matched YPR cohort was 83% -78% -78%, respectively. Mean follow-up was 3.6 years (SD 3.2) (r = 7-10). Over time, eight patients lost their graft, not related to surgical factors in seven out of eight cases.

CONCLUSION

The authors suggest that KT using YPD for age-match YPR yields good results in expert centers, even in high-risk patients and is associated with good graft survival. In this series, surgical complications were rarely related to graft loss.

Renal transplantation in children under 3 years of age: Experience from a single-center study

RTx remains challenging in children under 3 years of age. This single-center study reviewed the medical records of children <3 years transplanted since 1987 (N = 32, Group 1). They were matched for donor type and RTx period with children aged 3-13 years (N = 32, Group 2) and 13-18 years (N = 32, Group 3). There were no between-group significant differences regarding distributions of gender, primary renal disease, proportion of dialysis before RTx, and growth (SDS). Compared to Groups 2 and 3, Group 1 had more peritoneal dialyses (P < .001), more EBV mismatches (P = .04), and longer warm ischemia times (P < .001). The risk of graft loss was not significantly different among age groups (hazard ratio, 2.4 in Group 2 and 2.0 in Group 3 vs Group 1; P = .2). Death occurred in four patients (3 in Group 1 and 1 in Group 2) and graft loss occurred in 28 patients, mainly due to chronic allograft nephropathy. In recipients <3 years of age, the outcomes of RTx are close to those obtained in older pediatric age groups. Thus, young patients may be transplanted in experienced multidisciplinary teams without additional risks provided that particular attention is paid to donor selection and prevention/early diagnosis of comorbidities and complications.

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.

Renal transplantation in infants and small children

There are still concerns about renal transplantation in small children. The aim of this study was to identify prenatal data, underlying diseases, patient and graft survival, graft function and growth in young renal transplant recipients at our center. A retrospective analysis was performed on 50 kidney transplants performed during the period 1981-2008 in children weighing <13 kg. Their median age at transplantation was 1.4 (range 0.4-3.7) years and the median weight was 9.5 (3.4-12.1) kg. The underlying diseases were congenital in 88% of the patients and acquired in 12%. Ten-year patient survival was 88% (82% before 1998 and 95% since 1998). Ten-year graft survival was 82% (75 and 95%, respectively). Graft function (glomerular filtration rate) deteriorated from a mean of 75-48 ml/min/1.73 m(2) within 10 years. There was rapid catch-up growth within the first years post-transplant, from a median height of -2.44 standard deviation score (SDS) at transplantation to -0.74 SDS after 3 years. In small children, patient and graft survival were as good as those in older children. Renal function deteriorated during the first years post-transplant but stabilized within a few years. In most children, there was a substantial improvement in growth within the first years after transplantation.

Kidney transplantation complications related to psychiatric or neurological disorders

Defining absolute psychiatric or neurological contraindications among kidney transplantation candidates is controversial, especially taking into account that graft outcomes are similar to other groups of patients. The social support network should be exhaustively evaluated to ensure adherence to immunosuppressive therapy and minimization of complications resulting from the neuropsychiatric disorder. We reviewed transplants (n = 668) in our center between January 2001 and August 2008 searching for patients with a diagnosis of neurological or psychiatric disease before renal transplantation. We also reviewed demographic data, social support networks, patient and graft survivals as well as transplant complications. Twelve patients were transplanted with neurological or psychiatric disorders: seven with cognitive impairment and five with psychiatric diseases. Nine patients had good social support networks. The mean follow-up time was 2.65 +/- 2.42 years. The graft loss rate was 34% (n = 4), including only one attributed to a mental disorder, namely, nonadherence to immunosuppressive therapy. Regarding complications, four were related to the neuropsychiatric disorder: hypoglycemia due to insulin overdose, aspiration pneumonia because of altered pharynx-larynx motility, hyponatremia related to diuretic abuse, and malnutrition plus dehydration. Patient survival in this period was 91.7%. The one patient died due to multiple organ failure secondary to respiratory sepsis with a functioning graft. In summary, neuropsychiatric disorders should not be considered to be contraindications for kidney transplantation although a social support network is essential and must be carefully evaluated.

Long-term outcome of infants with severe chronic kidney disease

BACKGROUND AND OBJECTIVES

In 2000, we reported the outcome of 101 children with a GFR <20 ml/min per 1.73 m2 at 0.3 yr of age (range 0.0 to 1.5 yr). Long-term data on such young children are scarce.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Mortality, treatment modalities, and growth were reanalyzed 9.9 yr later.

RESULTS

Of the 101 patients, 28 died and three were lost to follow-up during 13.90 yr (range 0.03 to 22.90 yr). One-, 2-, 5-, 10-, 15-, 20-, and 22-yr survivals were 87, 81, 77, 75, 73, 72, and 64%, respectively. Fifty-one children had comorbidities. Sixty-six percent were tube fed for 1.7 yr (range 0.1 to 6.9 yr), 37% had a gastrostomy, and 13% had a Nissen fundoplication. Mean height SD score (SD) was -0.42 (2.33) at birth (n = 40), -2.07 (1.34) at 0.5 (n = 62), -1.93 (1.38) at 1 (n = 72), -1.14 (1.14) at 5 (n = 67), -1.04 (1.15) at 10 (n = 62), -1.84 (1.32) at 15 (n = 40), and -1.68 (1.52) at age > or =18 yr (n = 32). Comorbidities adversely influenced growth (P < 0.01) and final height (P = 0.02): Mean height SD score (SD) was -1.16 (1.38) in otherwise normal adults.

CONCLUSIONS

Growth and final height in infants with severe chronic kidney disease are influenced by comorbidity. Intensive feeding and early transplantation resulted in a mean adult height within the normal range in patients without comorbidities. Overall mortality is comparable to that of older children.

Outcomes of infants <28 days old treated with peritoneal dialysis for end-stage renal disease

This study evaluates the long-term outcomes of infants with end stage renal disease (ESRD) who required initiation of chronic peritoneal dialysis (PD) prior to 28 days of age. Infants with ESRD present both ethical and technical challenges for pediatric nephrologists and neonatologists. Recent advances in the medical management of ESRD in infants combined with improved infant transplantation outcomes make it more likely that such infants can survive to successful kidney transplantation. We reviewed all infants initiating PD for ESRD before 28 days of age at the University of Minnesota Amplatz Children's Hospital from 1995 to 2004 (n = 23). Overall 1 - and 5-year patient survival was 52 and 48%, respectively. Twelve children received kidney transplants at a median age and weight of 1.12 years and 9.5 kg, respectively, with a 5-year graft survival rate of 83%. In summary, a majority of infants requiring renal replacement therapy with PD in the first month of life achieve long-term survival with a successful kidney transplant.

Paediatric kidney transplantation in Belgium

In Belgium, kidney transplantation is currently the treatment of choice for a child with end-stage renal disease (ESRD). Dialysis remains the life-saving bridge to transplantation. Within the Eurotransplant (ET) community, Belgium represents 14% of the cadaveric transplantations and 22% of the living-related transplantation (LD) in children less than 16 years of age. Single-centre analysis (KUL) shows a patient survival of 94% at 3 year and 91% at 5 year. The overall graft survival is 82% at 3 year and 74% at 5 year. In the LD group, the graft survival rate is 10% better than the overall actuarial graft survival rate. Multivariate Cox regression analysis performed on all transplantations of one centre (KUL) demonstrate the following factors to be significant and independent predictors of poor graft outcome: absence of calcineurin inhibitors, two HLA- mismatches, duration of pre-transplant dialysis and creatinine clearance at one year after transplantation. The outcome improves by a short dialysis waiting time, the use of living-related donors, the prevention of delayed graft function (DGF), and of acute rejection. Within the ET community, the waiting child has priority compared to the adult, but if we want to avoid morbidity, waiting times must be shortened and the incidence of pre-emptive transplantation, which is currently 24% in Belgium, must increase. The good results with LD is certainly an attractive alternative to be actively encouraged for paediatric kidney recipients and the use of young deceased donors especially for children with ESRD must be supported since the results in terms of graft survival with these donors are very good, especially in children. In paediatric kidney transplantation the long-term graft survival is still the major challenge and has still to be documented by randomized trials. The success of the past, however, allows us to face the future with hope and confidence.

Avoiding steroids in pediatric renal transplantation: long-term experience from a single centre

We report our experience in pediatric renal transplantation avoiding steroids whenever possible. Immunosuppression consisted of an initial induction with antithymocyte globulin followed by maintenance therapy with a calcineurin inhibitor and MMF. Steroids were only given to selected patients because of the primary disease, recurrence, rejection, or PTLD. Thirty-four transplants grafted into 32 recipients between 1995 and 2005 were followed for a median of 3.5 yr (range 1-9.8). All patients survived. Graft rejection occurred in 10 cases during the first year post-transplantation and graft survival at one, five, and seven yr was 97, 88 and 88%, respectively. Steroids were given to half of the patients (n = 16); in nine cases due to rejection. Only four patients (13%) were continuously on steroids. Calculated GFR at one to five yr post-transplant were 73, 74, 68, 64, and 70 mL/min/1.73 m(2). Unfortunately PTLD occurred in three patients, but all survived with functioning grafts. Accordingly, our findings indicate that steroid avoidance in pediatric renal transplantation is possible with good results with respect to acute graft rejection as well as long-term graft survival.

Kidney transplantation in infants and small children

Transplantation is now the preferred treatment for children with end-stage kidney disease. But not all pediatric age groups have enjoyed the same success. The number of transplants in infants and young children has lagged behind the number in older children. One reason for this is the philosophy of some centers to maintain infants on dialysis until they reach some arbitrarily determined age, at which time they would undergo a transplant. If kidney transplantation is the therapy of choice for older children with renal failure, and equivalent results can be obtained in all age groups, why should it not be offered to these youngest patients? Our center's philosophy for many years has been not to restrict transplant based on size or age. We have performed over 50 kidney transplants in infant recipients, and have shown equivalent results to those obtained in older children. Important factors in obtaining a successful outcome include the use of adult kidneys from a living donor, careful attention to operative and perioperative care, and performing the transplant early or in a preemptive fashion. The latter allows for minimizing the negative impact of uremia on physical and neurologic development in infants.

Paediatric kidney transplantation in small children-- a single centre experience

Kidney transplantation (KTx) remains a challenging procedure in small children. This study presents our centre results. From 1983 to 2004, 40 of 442 paediatric KTx were performed in children with a body weight <11 kg. Median body weight was 9.2 kg (range: 7.2-10.9), median age was 2.7 years (range: 0.9-5.9). Preoperative dialysis was performed in 87.5%. In 24 cases (60%) grafts came from cadaveric (CAD) and in 16 cases (40%) from living related donors (LRD). Median donor age of CAD was 8 years (range: 1-40). The overall 1-, 5-, 10-, 15-year patient survival was 93%, 90%, 90% and 87% respectively. The overall 1-, 5-, 10-, 15-year graft survival was 90%, 80%, 66% and 56% respectively. There was no significant difference in survival of CAD or LRD grafts. Median follow-up was 13.7 years. Initial graft function rate was 100% for LRD and 79% for CAD. The relative glomerular filtration rate (GFR) showed no statistical difference between CAD and LRD. Main reasons for graft loss were chronic transplant nephropathy. Paediatric KTx is the treatment of choice even in very small children. Living donor KTx is the preferable donor source in terms of primary graft function and timing to transplantation.

First Living Related Kidney Transplantation Results in Excellent Outcomes for Small Children

OBJECTIVE

The aim of this study was to evaluated the outcomes of living related kidney transplantation in small children.

MATERIALS AND METHODS

Ten pediatric patients with body weights less than 10 kg received parental kidney transplants (five mothers and five fathers). An intra-abdominal approach was used in nine children and a retroperitoneal approach in one child. Bilateral, left, or right nephrectomy was performed in seven, two, and one child, respectively. Immunosuppression consisted of either cyclosporine (n = 7) or tacrolimus (n = 3) with either mizoribine (n = 4) or mycophenolate mofetil (MMF) (n = 5) or azathioprine (n = 1), and methylprednisolone (n = 10). Antilymphocyte globulin was used in the first series of four children; basiliximab in the most recent five children.

RESULTS

All renal allografts functioned immediately after transplantation despite the mismatched size of the large renal allografts. Nine of 10 children were alive with a functional allograft at 6 to 196 months posttransplantation. One child died of intra-abdominal bleeding 5 days posttransplantation. One child has suffered chronic allograft nephropathy 11 years posttransplantation (serum creatinine 3.3 mg/dL). The remaining eight children display good renal function (serum creatinine = 0.2 to 1.43 mg/dL). Steroids were withdrawn in eight of nine children; one child continues on alternative-day therapy. One child (LD55) exceeded the mean standard height. The most recent height standard deviation (SD) scores were superior (-1.75 +/- 1.39 [-3.83 to 0.54]; P < .0082) to those at transplantation (-2.91 +/- 0.79 [-2.00 to -4.14]).

CONCLUSIONS

The outcomes of living related kidney transplantation in small children were excellent despite the operative risks and the difficulty of cardiovascular and fluid management. Transplantation for small children appears to result in much better quality of life and growth than dialysis.

Cadaveric Kidney Transplantation in Children ≤20 kg in Weight: Long-Term Single-Center Experience

BACKGROUND

We report long-term follow-up data on cadaveric kidney transplantation in children < or =20 kg in weight.

METHODS

Between January 1990 and October 2003, we performed 19 cadaveric renal transplants in 19 children < or =20 kg in weight. Mean age at transplantation was 4.7 years (range 18 months to 9 years). Mean weight at transplantation was 14.4 kg (range 9 to 20 kg). Nine patients had preemptive kidney transplantation, whereas 10 were maintained on renal replacement therapy before the transplant operation.

RESULTS

Actuarial 1-, 3-, 5-, and 10-year patient survival rates were 89.5%, 89.5%, 89.5%, and 82%, respectively. Actuarial 1-, 3-, 5-, and 10-year graft survival rates were 79%, 73%, 73%, 65%, respectively. Three patients died. Eight grafts failed. Cause of graft failure was death with a functioning graft in 3 patients, chronic rejection in 1, acute cellular rejection in 1, vascular rejection in 1, hemolytic-uremic syndrome in 1, and unknown in 1.

CONCLUSIONS

Our results indicate the success of cadaveric kidney transplantation in the very small child with results comparable to living related donor transplantation.