Pediatric Kidney Transplant Research Articles

Valacyclovir or valganciclovir for cytomegalovirus prophylaxis: A randomized controlled trial in adult and pediatric kidney transplant recipients

BackgroundValganciclovir (valG), a cytomegalovirus (CMV) prophylactic agent, has dose-limiting side effects. The tolerability and effectiveness of valacyclovir (valA) as CMV prophylaxis is unknown. MethodsWe conducted a randomized, open-label, single-center trial of valA versus valG for all posttransplant CMV prophylaxis in adult and pediatric kidney recipients. Participants were randomly assigned to receive valA or valG. Primary endpoints were the incidence of CMV viremia and side-effect related drug reduction with secondary assessment of incidence of EBV viremia. ResultsOf the 137 sequential kidney transplant recipients enrolled, 26 % were positive and negative for CMV antibody in donor and recipient respectively. The incidence of CMV viremia (4 of 71 [6 %]; 8 of 67 [12 %] P = 0.23), time to viremia (P = 0.16) and area under CMV viral load time curve (P = 0.19) were not significantly different. ValG participants were significantly more likely to require side-effect related dose reduction (15/71 [21 %] versus 1/66 [2 %] P = 0.0003). Leukopenia was the most common reason for valG dose reduction and granulocyte-colony stimulating factor was utilized for leukopenia recovery more frequently (25 % in valG vs 5 % in valA: P = 0.0007). Incidence of EBV viremia was not significantly different. ConclusionsValA has significantly less dose-limiting side effects than valG. In our study population, a significant increase in CMV viremia was not observed, in adults and children after kidney transplant, compared to valG. Trial Registration NumberNCT01329185

Growth after pediatric kidney transplantation: a 25-year study in a pediatric kidney transplant center.

Growth failure is one of the major complications of pediatric chronic kidney disease. Even after a kidney transplant (KT), up to 50 % of patients fail to achieve the expected final height. This study aimed to assess longitudinal growth after KT and identify factors influencing it. A retrospective observational study was performed. We reviewed the clinical records of all patients who underwent KT for 25 years in a single center (n=149) and performed telephone interviews. Height-for-age and body mass index (BMI)-for-age were examined at KT, 3months, 6months, 1 year, and 5 years post-transplant and at the transition to adult care. We evaluated target height, disease duration before KT, need and type of dialysis, recombinant human growth hormone pretransplant use, nutritional support, glomerular filtration rate (GFR), and cumulative corticosteroid dose. At transplant, the average height z-score was-1.38, and height z-scores showed catch-up growth at 6months (z-score-1.26, p=0.006), 1 year (z-score-1.15, p<0.001), 5 years after KT (z-score-1.08, p<0.001), and on transition to adult care (z-score-1.22, p=0.012). Regarding BMI z-scores, a significant increase was also detected at all time points (p<0.001). After KT, GFR was significantly associated with height z-score (p=0.006) and BMI z-score (p=0.006). The height in transition to adult care was-1.28 SD compared to the target height. Despite the encouraging results regarding catch-up growth after KT in this cohort, results remain far from optimum, with a lower-than-expected height at the time of transition.

Long-term outcomes of two-dose alemtuzumab induction in pediatric kidney transplantation.

Alemtuzumab is a lymphocyte depleting agent used for induction in kidney transplant, but long-term information on its use in pediatric recipients remains sparse. We performed a single-center retrospective cohort study of 57 pediatric kidney transplant recipients receiving alemtuzumab 20 mg/m2/dose ×2 doses for induction immunosuppression. All patients underwent surveillance biopsies, and 91.3% underwent steroid withdrawal by day 4 post-transplant. Outcomes of interest included graft survival, development of donor specific antibodies (DSA), incidence of viremia and PTLD, and duration of lymphopenia. Median follow-up time was 7.9 years (IQR 5-13.6 years). Median graft survival was 16.5 years (95% CI 11.6-unknown). DSA developed in 36.5% at a median of 944 days (IQR 252-2113 days). Incidences of BK polyomavirus DNAemia (BKPyV-DNAemia), CMV DNAemia, and EBV DNAemia were 38.6%, 22.8%, and 14%, respectively; one patient developed PTLD at 13.3 years post-transplant. Median duration of lymphopenia was 365 days (IQR 168-713 days); 19.3% of patients remained lymphopenic at 3 years post-transplant. There was no association between duration of lymphopenia and graft survival, rejection, DSA detection, or viremia. A two-dose alemtuzumab induction protocol can have excellent outcomes with a steroid-free maintenance immunosuppression regimen. More comprehensive, multicenter, comparative studies of pediatric kidney transplant are needed to improve long-term outcomes.

Let's get physical: Aerobic capacity, muscle strength, and muscle endurance after pediatric heart transplantation.

Pediatric heart (HTx) and kidney transplant (KTx) recipients may have lower physical fitness than healthy children. This study sought to quantify fitness levels in transplant recipients, investigate associations to clinical factors and quality of life, and identify whether a quick, simple wall-sit test is feasible as a surrogate for overall fitness for longitudinal assessment. Aerobic capacity (6-min walk test, 6MWT), normalized muscle strength, muscle endurance, physical activity questionnaire (PAQ), and quality of life (PedsQL™) were prospectively assessed in transplanted children and matched healthy controls. Twenty-two HTx were compared to 20 controls and 6 KTx. 6MWT %predicted was shorter in HTx (87.2 [69.9-118.6] %) than controls (99.9 [80.4-120] %), but similar to KTx (90.3 [78.6-115] %). Muscle strength was lower in HTx deltoids (6.15 [4.35-11.3] kg/m2) and KTx quadriceps (9.27 [8.65-19.1] kg/m2) versus controls. Similarly, muscle endurance was lower in HTx push-ups (28.6 [0-250] %predicted), KTx push-ups (8.35 [0-150] %predicted), HTx curl-ups (115 [0-450] %predicted), and KTx wall-sit time (18.5 [10.0-54.0] s) than controls. In contrast to HTx with only 9%, all KTx were receiving steroid therapy. The wall-sit test significantly correlated with other fitness parameters (normalized quadriceps strength R = .31, #push-ups R = .39, and #curl-ups R = .43) and PedsQL™ (R = .36). Compared to controls, pediatric HTx and KTx have similarly lower aerobic capacity, but different deficits in muscle strength, likely related to steroid therapy in KTx. The convenient wall-sit test correlates with fitness and reported quality of life, and thus could be a useful easy routine for longitudinal assessment.

Metabolic Acidosis Is Associated With an Accelerated Decline of Allograft Function in Pediatric Kidney Transplantation

AimsWe investigated the relationship between metabolic acidosis over time and allograft outcome in pediatric kidney transplantation. MethodsThis registry study collected data up to 10 years posttransplant. Survival analysis for a composite endpoint of graft loss or estimated glomerular filtration rate (eGFR) ≤30 mL/min per 1.73 m2 or ≥50% decline from eGFR at month 3 posttransplant was performed. The association of HCO3-<22 mmol/L (metabolic acidosis) and HCO3-<18 mmol/L (severe metabolic acidosis) with allograft outcome was investigated using stratified Cox models and marginal structural models. Secondary analyses included the identification of risk factors for metabolic acidosis and the relationship between alkali supplementation and allograft outcome. ResultsWe report on 1911 patients, of whom 347 reached the composite endpoint. The prevalence of metabolic acidosis over time ranged from 20.4% to 38.9%. In the adjusted Cox models, metabolic acidosis (hazard ratio [HR],2.00; 95% confidence interval [CI], 1.54 to 2.60) and severe metabolic acidosis (HR,2.49; 95%CI, 1.56 to 3.99) were associated with allograft dysfunction. Marginal structural models showed similar results (HR,1.75; 95%CI, 1.32 to 2.31 and HR,2.09; 95%CI, 1.23 to 3.55, respectively). Older age was associated with a lower risk of metabolic acidosis (odds ratio (OR) 0.93 per year older; 95% CI, 0.91 to 0.96) and severe metabolic acidosis (OR, 0.89; 95% CI, 0.84 to 0.95). Patients with uncontrolled metabolic acidosis had the worst outcome compared to those without metabolic acidosis and without alkali (HR, 3.70; 95% CI, 2.54 to 5.40) ConclusionThe degree of metabolic acidosis is associated with allograft dysfunction.

Kidney transplant in pediatric gut transplant recipients - Technical challenges and outcomes.

There is limited data in the literature about pediatric kidney transplant (KT) following gut transplant (GT). The purpose of this study is to highlight the technical challenges and outcomes of KT in pediatric gut recipients who developed kidney failure (KF). A retrospective single-center study of pediatric GT recipients from January 2000 to December 2019 was performed. In total, 14 (7%) out of 206 pediatric GT recipients developed KF and were listed for KT. Ten patients underwent kidney after gut transplant (KAGT), three patients underwent simultaneous kidney and re-do gut transplant (SKAGT), and one patient died on the KT waitlist. 1-, 5-, and 10-year kidney graft survival was 100%, 91%, and 78%, respectively. 1-, 5-, and 10-year GT graft survival was 100%, 77%, and 77%, respectively. 1-, 5-, and 10-year patient survival was 100%, 91%, and 91%, respectively. Despite the technical complexity, KAGT and SKAGT for pediatric GT recipients that develop KF can be performed with favorable outcomes.

Effect of pre-emptive rituximab on EBV DNA levels and prevention of post-transplant lymphoproliferative disorder in pediatric kidney transplant recipients: A case series from the pediatric nephrology research consortium.

There are scant data on the effect of rituximab on EBV DNA levels and prevention of post-transplant lymphoproliferative disorder (PTLD) in pediatric kidney transplant recipients with EBV DNAemia. Kidney transplant recipients with EBV DNAemia treated with rituximab to prevent PTLD between 7/1999 and 7/2019 at five pediatric centers were included. Those with confirmed PTLD at the onset of rituximab were excluded. Primary outcomes included percentage change in EBV DNAemia and occurrence of PTLD post rituximab. Twenty-six pediatric kidney transplant recipients were included. Median age at transplant was 4 years (IQR 2.1-10.3). EBV DNA load monitoring by qPCR was performed at 1-3 month intervals. EBV DNAemia onset occurred at a median of 73 days post-transplant (IQR 52-307), followed by DNAemia peak at a median of 268 days (IQR 112-536). Rituximab was administered at a median of 9 days post peak (IQR 0-118). Rituximab regimens varied; median dose 375 mg/m2 (IQR 375-439) weekly for 1-4 doses per course. Following rituximab, EBV DNA load decreased to <10% of baseline at 120 days in 20/26 patients; however, only 30% achieved complete resolution at last follow-up (median 2094 days post-transplant [IQR 1538-3463]). Two (7%) developed PTLD at 915 and 1713 days post rituximab. All recipients had functioning grafts. One death occurred in a child with PTLD following remission due to unrelated reasons. In the largest pediatric kidney transplant recipient case series with EBV DNAemia given rituximab to prevent PTLD, rituximab achieved a short-term reduction in DNA load; however, recurrent DNAemia is common.

WCN24-1875 Central Blood Pressure Monitoring in Pediatric Kidney Transplant Recipients: A Comprehensive Evaluation

WCN24-1875 Central Blood Pressure Monitoring in Pediatric Kidney Transplant Recipients: A Comprehensive Evaluation

481 Social Deprivation Does Not Affect Pediatric Kidney Transplant Wait Listing

481 Social Deprivation Does Not Affect Pediatric Kidney Transplant Wait Listing

Pediatric Transplant Experience from a Single Center in South India

Background and Objective: Pediatric renal transplantation is a life-saving procedure for children with end-stage renal disease. This study aims to analyze the outcomes of pediatric renal transplants at our center, focusing on patient demographics, donor sources, surgical techniques, posttransplant complications, graft survival, and rejection rates. Methodology: A retrospective analysis was conducted on 43 pediatric kidney transplant recipients. Data on recipient age, gender, donor type, pretransplant dialysis, donor characteristics, surgical techniques, native kidney disease, induction therapy, maintenance immunosuppression, posttransplant infections, graft survival, and rejection episodes were collected and analyzed. Results: We performed 43 pediatric kidney transplants in total. The average age was 13.7 years (±3.81), with 8 (18.6%) being under the age of ten, 11 (25.6%) being between the ages of eleven and fourteen, and 24 (55.8%) being between the ages of fifteen and eighteen. There were 43 recipients: 27 males and 16 females. There were four (9.3%) deceased donor renal transplants and 39 (90.7%) live-related kidney transplants. Right internal iliac artery and right external iliac vein anastomosis were found in 32 (74.4%) cases, right external iliac artery and right external iliac vein in 9 (20.9%), right common iliac artery and right common iliac vein in 1 (2.3%), and right common iliac and right internal iliac in 1 (2.3%). Induction was used in 27 recipients (62.8%). Graft survival was seen at 1 year in 42 (97.7%) patients and at 5 years in 34 (81%). Biopsy-proven rejection occurred in 22 (51.2%) of the recipients, with antibody-mediated rejection occurring in 8 (18.6%) and cellular rejection occurring in 22 (51.2%). Graft loss was caused by acute cellular rejection in three (23.1%) cases, graft pyelonephritis in 2 (15.4%), and an unknown cause in 2 (15.4%). There were no significant connections with antibody-mediated rejection. Conclusion: Our study provides valuable insights into the outcomes of pediatric renal transplantation at our center. Despite the challenges of graft rejection and posttransplant infections, favorable graft survival rates were achieved. Cellular rejection emerged as a significant risk factor for graft survival, highlighting the importance of effective immunosuppressive management. Our findings emphasize the need for close follow-up, infection control measures, and individualized immunosuppressive strategies to optimize long-term outcomes in pediatric renal transplant recipients. Further research is warranted to refine protocols and address the specific needs of this vulnerable patient population.

WCN24-2600 Tuberculosis in pediatric kidney transplant recipients: 35 years of experience

WCN24-2600 Tuberculosis in pediatric kidney transplant recipients: 35 years of experience

Optimizing the approach to monitoring allograft inflammation using serial urinary CXCL10/creatinine testing in pediatric kidney transplant recipients.

Urinary CXCL10/creatinine (uCXCL10/Cr) is proposed as an effective biomarker of subclinical rejection in pediatric kidney transplant recipients. This study objective was to model implementation in the clinical setting. Banked urine samples at a single center were tested for uCXCL10/Cr to validate published thresholds for rejection diagnosis (>80% specificity). The positive predictive value (PPV) for rejection diagnosis for uCXCL10/Cr-indicated biopsy was modeled with first-positive versus two-test-positive approaches, with accounting for changes associated with urinary tract infection (UTI), BK and CMV viremia, and subsequent recovery. Seventy patients aged 10.5 ± 5.6 years at transplant (60% male) had n = 726 urine samples with n = 236 associated biopsies (no rejection = 167, borderline = 51, and Banff 1A = 18). A threshold of 12 ng/mmol was validated for Banff 1A versus no-rejection diagnosis (AUC = 0.74, 95% CI = 0.57-0.92). The first-positive test approach (n = 69) did not resolve a clinical diagnosis in 38 cases (55%), whereas the two-test approach resolved a clinical diagnosis in the majority as BK (n = 17/60, 28%), CMV (n = 4/60, 7%), UTI (n = 8/60, 13%), clinical rejection (n = 5/60, 8%), and transient elevation (n = 18, 30%). In those without a resolved clinical diagnosis, PPV from biopsy for subclinical rejection is 24% and 71% (p = .017), for first-test versus two-test models, respectively. After rejection treatment, uCXCL10/Cr level changes were all concordant with change in it-score. Sustained uCXCL10/Cr after CMV and BK viremia resolution was associated with later acute rejection. Urinary CXCL10/Cr reliably identifies kidney allograft inflammation. These data support a two-test approach to reliably exclude other clinically identifiable sources of inflammation, for kidney biopsy indication to rule out subclinical rejection.

Efficacy and safety of single-dose anti-thymocyte globulin versus basiliximab induction therapy in pediatric kidney transplant recipients: A retrospective comparative cohort study.

This study aimed to compare the efficacy and safety of basiliximab (BAS) versus a single dose of anti-thymocyte globulin (r-ATG) induction therapy in pediatric kidney transplant recipients (KTRs). This single-center retrospective comparative cohort study included all pediatric KTRs from May 2013 to April 2018 and followed up to 12 months. In the first period, all recipients received BAS, while from May 2016, a single 3 mg/kg dose of r-ATG was instituted. Maintenance therapy consisted of a calcineurin inhibitor plus prednisone plus azathioprine or mycophenolate. A total of 227 patients were included (BAS, n = 113; r-ATG, n = 114). The main combination of immunosuppressive drugs was tacrolimus, prednisone, and azathioprine in both groups (87% vs. 88%, p = .718). Patients receiving r-ATG showed superior survival-free of the composite endpoint (acute rejection, graft loss, or death; 76% vs. 61%, p = .003; HR 2.08, 1.29-3.34, p = .003) and lower incidence of biopsy-proven acute rejection (10% vs. 21%, p = .015). There was no difference in the overall incidence of CMV infection (33% vs. 37%, p = .457), PTLD (1% vs. 3%, p = .309), 30-day hospital readmissions (24% vs. 23%, p = .847), and kidney function at 12 months (86 ± 29 vs. 84 ± 30 mL/min/1.73m2, p = .614). These data suggest that induction therapy with a single 3 mg/kg dose of r-ATG is associated with higher efficacy for preventing acute rejection and similar safety profile compared to BAS.

The humoral immune response to the BNT 162B2 vaccine in pediatrics on renal replacement therapy.

Since the start of the COVID-19 pandemic, data published on the immunogenicity of the SARS-CoV-2 BNT 162B2 vaccine in pediatric patients receiving renal replacement therapy are scant. Our primary objective is to study this population's humoral immune response to the COVID-19 vaccine. Pediatric kidney transplant recipients (PKTRs) and hemodialysis recipients (HR) at our center who received two doses of the SARS-CoV-2 BNT 162B2 vaccine were included. Transplant and HR who had PCR-positive COVID-19 infections during the study, regardless of their vaccine status, were also included. SARS-CoV-2 anti-spike protein (S1/S2) IgG was measured after the second dose of the vaccine and after any PCR-positive COVID-19 infection as routine clinical practice. Data on demographics, induction, maintenance immunosuppressants, type of transplant, and posttransplant or dialysis duration were included. Of the 61 patients included, 19 were dialysis recipients who received two doses of vaccine without subsequent infection (HV), and 42 were kidney transplant recipients. All dialysis patients and 33 (78.6%) transplant recipients received two doses of the SARS-CoV-2 BNT 162b2 vaccine. A total of 33.3% (11/33) of the transplant recipients who received vaccination developed COVID-19 infection (KTH) at a median time of 13 days after the second dose of vaccine. Nine transplant patients had pure COVID-19 infection without vaccination (KTI). The seroconversion rate in the HV group was 94.7% (18/19) compared to 50% (11/22) in the kidney transplant vaccine recipients who did not develop subsequent COVID-19 infection (KTV) (p < .001). The median S1/S2 IgG titers for the HV group were 400 AU/mL versus 15 AU/mL in the KTV group (p < .0001). There was no significant difference in the duration of the test from the second dose of the vaccine between HV and KTV (55 vs. 33.5 days, p = .095). The KTH had higher titers than KTV group (370 vs. 15 p < .0001). The median duration of the test after vaccination in the vaccine group and those with hybrid immunity was similar (35 vs. 33.5 days, p = .2).There were no clear predictors for seroconversion in the PKTRs. Natural infection alone was as good as the vaccine in eliciting humoral immune response. The humoral immune response to two doses of the SARS-CoV-2 BNT 162B2 vaccine in PKTRs without subsequent COVID-19 infection is suboptimal compared to that in hemodialysis recipients and in PKTRs with hybrid immunity from both infection and vaccination.

The association of Torque Teno viral load with CMV and BKV infection in pediatric and adolescent kidney transplant patients.

Background: Long-term allograft and patient survival after kidney transplantation (KTX) depends on the balance between over- and under-immunosuppression (IS). High levels of IS predispose to opportunistic infections. Plasma load of Torque Teno Virus (TTV), a non-pathogenic highly prevalent Annellovirus, is associated with its hosts immune status, especially after solid organ transplantation. Objectives: To investigate the association of plasma TTV load and opportunistic viral infections after pediatric KTX. Study design: This retrospective study includes all pediatric KTX patients followed at the Medical University of Vienna 2014–2020. PCR for Cytomegalovirus (CMV), Epstein-Barr virus (EBV), BK virus (BKV), and TTV was performed every 4–8 weeks at routine follow-up visits. Results: 71 pediatric KTX patients were followed with TTV measurements for a median of 2.7 years. TTV plasma load was associated with CMV DNAemia at the next visit with an OR of 2.37 (95 % CI 1.15–4.87; p = 0.03) after adjustment for time after KTX and recipient age. For a cut-off of 7.68 log10 c/mL TTV a sensitivity of 100 %, a specificity of 61 %, a NPV 100 %, and a PPV of 46 % to detect CMV DNAemia at the next visit was calculated. TTV plasma loads were also associated with BKV DNAuria and BKV DNAemia at the next visit, but not with EBV DNAemia. Conclusions: This is the first study to analyse associations between TTV plasma loads and opportunistic viral infections in pediatric KTX. We were able to present a TTV cut-off for the prediction of clinically relevant CMV DNAemia that might be useful in clinical care.

A novel approach to bladder cycling for defunctionalized bladders prior to pediatric kidney transplantation: A case series

Ensuring a safe reservoir for pediatric renal transplantation into a defunctionalized bladder is a challenge faced by urologists. We present three patients with defunctionalized bladders who initiated bladder cycling utilizing overnight continuous saline infusion via enteral feeding pump for bladder salvage and subsequent transplantation.

Pediatric kidney transplantation: is it safe to perform during night-time or day-off?

PurposeTo investigate the impact of after-hours surgery on the outcomes of pediatric kidney transplantation (KT).MethodsMedical records of pediatric KTs performed at a single institution between 2013 and 2021 were retrospectively reviewed. The population was split into three groups according to the incision time and calendar: ordinary day (8.00 AM – 6.30 PM), day-off, and night-time (6.30 PM – 8.00 AM). The following endpoints were compared: ischemia times, length of surgery, complications, delayed graft function (DGF), primary graft non-function (PGNF), and eGFR at three-month follow-up.ResultsNinety-six non-living donor KTs were performed, median age 11 (IQR 4.3–14) years and median body weight 26 (IQR 13–50) kg. Forty-one (43%) were performed during night-time and 28 (29%) during day-off. Ischemia times were similar (p = 0.769, p = 0.536). Day-off KTs presented an extended length of surgery (p = 0.011). Thirty-two complications were reported in 31 KTs. No difference in the overall rate of complications, DGF, PNGF, and three-month eGFR was found (p = 0.669, p = 0.383, p = 0.949, p = 0.093). Post-operative bleedings were more common in days-off (p = 0.003).ConclusionThe number of pediatric KTs performed during after-hours was considerable. Even though similar outcomes were reported, more caution should be focused on the KTs performed in days-off to avoid severe complications.

Oral findings in paediatric patients with severe heart, liver, and kidney failure prior to organ transplantation

PurposeOrgan transplantation is an effective treatment for children with severe heart, liver, and kidney diseases. These patient groups may have more oral and dental diseases than healthy controls. It is important to eliminate oral infection foci before transplantation and to maintain good oral health to avoid potential post-transplant complications. The aim of this study was to describe and compare oral health in Finnish paediatric heart, liver, and kidney transplant recipients prior to organ transplantation.MethodsEighty-six children who received a heart (n = 21), liver (n = 19), or kidney (n = 46) transplant in Finland during the years 2014–2018 were included in this study. The inclusion criterion was a pre-transplantation oral examination. Oral hygiene, enamel anomalies, and the number of decayed, missing, and filled teeth (dmft/DMFT) were analyzed retrospectively from medical and dental records and compared between the three patient groups.ResultsChildren with liver (p = 0.043) or heart (p = 0.047) disease had higher combined primary and permanent dentition dmft/DMFT scores compared to children with kidney disease. A higher combined dmft/DMFT score was associated with poor oral hygiene (p = 0.005). No significant differences in oral hygiene between the patient groups were found. Furthermore, all patient groups had a high prevalence of developmental dental defects.ConclusionChildren with liver or heart disease seem to have a higher combined dmft/DMFT score, indicating a higher prevalence of caries compared to children with kidney disease. Prevention of dental caries, along with promoting a good oral hygiene routine and regular check-ups, is suggested in these patient groups.

Comparison of estimated GFR using cystatin C versus creatinine in pediatric kidney transplant recipients

BackgroundAn accurate, rapid estimate of glomerular filtration rate (GFR) in kidney transplant patients affords early detection of transplant deterioration and timely intervention. This study compared the performance of serum creatinine (Cr) and cystatin C (CysC)-based GFR equations to measured GFR (mGFR) using iohexol among pediatric kidney transplant recipients.MethodsCysC, Cr, and mGFR were obtained from 45 kidney transplant patients, 1–18 years old. Cr- and CysC-estimated GFR (eGFR) was compared against mGFR using the Cr-based (Bedside Schwartz, U25-Cr), CysC-based (Gentian CysC, CAPA, U25-CysC), and Cr-CysC combination (CKiD Cr-CysC, U25 Cr-CysC) equations in terms of bias, precision, and accuracy. Bland–Altman plots assessed the agreement between eGFR and mGFR. Secondary analyses evaluated the formulas in patients with biopsy-proven histological changes, and K/DOQI CKD staging.ResultsBias was small with Gentian CysC (0.1 ml/min/1.73 m2); 88.9% and 37.8% of U25-CysC estimations were within 30% and 10% of mGFR, respectively. In subjects with histological changes on biopsy, Gentian CysC had a small bias and U25-CysC were more accurate—both with 83.3% of and 41.7% of estimates within 30% and 10% mGFR, respectively. Precision was better with U25-CysC, CKiD Cr-CysC, and U25 Cr-CysC. Bland–Altman plots showed the Bedside Schwartz, Gentian CysC, CAPA, and U25-CysC tend to overestimate GFR when > 100 ml/min/1.72 m2. CAPA misclassified CKD stage the least (whole cohort 24.4%, histological changes on biopsy 33.3%).ConclusionsIn this small cohort, CysC-based equations with or without Cr may have better bias, precision, and accuracy in predicting GFR.Graphical abstractA higher resolution version of the Graphical abstract is available as Supplementary information

Determinants of hyperparathyroidism in children after kidney transplantation.

Hyperparathyroidism (HPT) can contribute to metabolic bone disease following kidney transplantation. We evaluated post-transplant trends in intact parathyroid hormone (iPTH) and determined predictors of HPT in pediatric kidney transplant (KTx) recipients. In this single-center study, retrospective data were collected on 88 children from 2013 to 2019. Data collected included dialysis vintage, biochemical parameters, post-transplant trends in iPTH, 25(OH)Vitamin D levels and estimated glomerular filtration rate (eGFR ml/min/1.73 m2 ). Pre-transplant treatment for HPT was quantified with a Treatment Burden score (TB, score range: 0-100). After log-transforming skewed variables (iPTH and eGFR), multivariable linear regression was performed to determine predictors of log {iPTH} at 6 and 36 months (mo) post-transplant. Median age was 12.8 (range: 1.9-20.5) years, and dialysis vintage was 11.2 (range:0.0-112.9) months. The majority were of Hispanic and African Ancestry (77.3%). Median post-transplant iPTH was 69.5 (range: 1.8-306.8) pg/ml at 6mo with a gradual downward trend to 59.0 (range: 28.0-445.0) pg/ml at 36mo. Significant multivariable predictors of higher log {iPTH} post-transplant included longer dialysis vintage, higher TB, and lower log{eGFR} at 6mo, and higher TB, lower log{eGFR}, and deceased donor transplant at 36mo. Recognition of risk factors for HPT and monitoring iPTH post-transplant may facilitate timely interventions to mitigate cardiovascular and bone disease in pediatric KTx recipients. Describe serial trends in intact PTH after kidney transplantation. Pre- and post-transplant factors that contribute to persistence or re-occurrence of hyperparathyroidism after kidney transplantation in children include longer dialysis vintage, high pre-transplant treatment burden and decreased post-transplant GFR. Recognition of these factors, and monitoring intact PTH after kidney transplantation, could facilitate timely interventions to mitigate cardiovascular and bone disease in children.