First clinical application of cord blood mesenchymal stromal cells in children with multi-drug resistant nephrotic syndrome

Background and objectives

Children with multi-drug resistant idiopathic nephrotic syndrome (MDR-INS) usually progress to end-stage kidney disease with a consistent risk of disease recurrence after transplantation. New therapeutic options are needed for these patients. Mesenchymal stromal cells (MSCs) are multipotential non-hematopoietic cells with several immunomodulatory properties and growing clinical applications. Cord blood-derived MSC have peculiar anti-inflammatory and immunosuppressive properties. We aimed at assessing safety and efficacy of cord-blood-derived MSCs (CB-MSCs) in children with MDR-INS.

Design, setting, participants

Prospective, open-label, single arm phase I–II pilot study. Pediatric patients with MDR-INS, resistant to at least two lines of therapy, were enrolled. Allogenic CB-MSCs were administered intravenously on days 0, 14, and 21 at a dose of 1.5 × 10⁶ cells/kg. Patients were followed for at least 12 months. The primary outcomes were safety and toxicity. The secondary outcome was remission at 12 months evaluated by urinary protein/urinary creatinine ratio (uPr/uCr). Circulating regulatory T cells (Tregs) were monitored.

Results

Eleven pediatric patients with MDR-INS (10 females, median age 13 years) resistant to a median of 3 previous lines of therapy were enrolled. All patients completed the CB-MSC infusion schedule. No patient experienced any infusion-related adverse event or toxicity. Nine patients were assessable for efficacy. At the 12 months follow-up after the treatment, the median uPr/uCr did not change significantly from baseline (8.13 vs. 9.07; p = 0.98), while 3 patients were in partial or complete remission. A lower baseline uPr/uCr was a predictor of remission (2.55 vs. 8.74; p = 0.0238). Tregs count was not associated with CB-MSCs therapy.

Conclusions

CB-MSCs are safe and may have a role in the immunosuppressive therapy of pediatric patients with MDR-INS. This preliminary experience paves the way toward further phase II studies addressing MSC efficacy in immune-mediated kidney diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03112-7.

Childhood Idiopathic Nephrotic Syndrome: Does the Initial Steroid Treatment Modify the Outcome? A Multicentre, Prospective Cohort Study

Background: A great majority of children with idiopathic nephrotic syndrome will relapse after successful treatment of the initial episode. The possibility that different steroid dosing regimens at onset, adjusted for risk factors, can reduce the rate of relapse represents an interesting option to investigate. Objectives: To evaluate the effect of the initial steroid regimen, adjusted for time to remission (TTR), on the frequency of relapses and steroid dependence, and to verify the influence of prognostic factors on disease course. Methods: A multicentre, prospective, cohort study. Children with nephrotic syndrome, with TTR ≤ 10 days (Group A), were given a 20-week prednisone regimen (2,828 mg/m2) and those with a TTR >10 days, a 22-week regimen (3,668 mg/m2) (Group B). Previously published retrospective data from the same centers were also evaluated. Main outcomes were: relapse rate, number of frequent relapsers + steroid dependent children and total prednisone dose after induction. Results: 143 children were enrolled. Rate of relapsed subjects (77 vs. 79%) and frequent relapsers + steroid dependent subjects (40 vs. 53%) did not differ between Groups A and B, or between the retrospective and prospective cohorts. The cumulative prednisone dose taken after the induction treatment was similar in both groups and in the retrospective and prospective cohorts. TTR was not associated with relapse risk. Age at onset and total serum protein were significantly lower in relapsing patients. At ROC analysis, the best cut-off was 5.3 years for age at onset and 4.2 g/dL for total serum protein. According to these cut-offs, older children with higher total serum protein had a higher relapse free survival rate (58%) than younger children with lower total serum protein (17%). Conclusions: TTR was not found to be a prognostic factor of relapse; because of this, different steroid regimens, adjusted for TTR, did not modify the relapse rate in any relevant measure. Conversely, younger age and low total serum protein were independent predictors of relapse risk, however this outcome was not modified by higher prednisone regimens. Clinical Trial Registration:https://www.ClinicalTrials.gov/, identifier: NCT01386957 (www.nefrokid.it).

CYP and SXR gene polymorphisms influence in opposite ways acute rejection rate in pediatric patients with renal transplant

Background

We evaluated the role of CYP3A5, ABCB1 and SXR gene polymorphisms in the occurrence of acute kidney rejection in a cohort of pediatric renal transplant recipients.

Methods

Forty-nine patients were genotyped for CYP3A5, ABCB1 and SXR polymorphisms and evaluated with tacrolimus through levels in a retrospective monocenter study.

Results

Patients with the A allele of CYP3A5 treated with tacrolimus had a higher risk of acute rejection than those without the A allele, while patients carrying the homozygous GG variant for SXR A7635GG did not show any episode of acute rejection.

Conclusion

Genetic analysis of polymorphisms implicated in drug metabolism and tacrolimus trough levels may help to forecast the risk of acute rejection and individualize drug dosage in children undergoing renal transplantation.

Prevalence of Malnutrition Assessed by Bioimpedance Analysis and Anthropometry in Children on Peritoneal Dialysis

Objective

To evaluate the sensitivity of anthropometry and bioelectrical impedance analysis (BIA) in detecting alterations in body composition of children treated with peritoneal dialysis (PD), and to determine the prevalence of malnutrition in this population, in short- and long-term PD duration, using anthropometric and BIA-derived indices.

Patients

Eighteen children treated with automated PD (11 males, 7 females; mean age 8.7 ± 4.7 years).

Design

Eighteen patients were studied using anthropometry and BIA at the start (t0) and after 6 months (t1) of PD, 15 of these patients at 12 months (t2), and 8 at 24 months (t3) of PD. Midarm muscle circumference (MAMC), arm muscle area (AMA), and arm fat area (AFA) were calculated from anthropometric measures according to Frisancho (FrisanchoAR. New norms of upper limb fat and muscle areas for assessment of nutritional status. Am J Clin Nutr 1981; 34:2540–5.). The bioelectrical measures of resistance (R) and reactance (Xc) were obtained directly from the impedance signal; phase angle (PA) and distance (D) were calculated using mathematical formulas. Nutritional status was assessed by anthropometric measurements and BIA-derived indices, expressed as standard deviation scores (SDS), and by a score system based on BIA and anthropometric parameters. The percentage of children with values of anthropometric and BIA-derived indices below the 3rd percentile or between the 3rd and 25th percentiles, and the percentage of children with scores of 7 – 12 and 4 – 6 were calculated in order to detect patients with severe or moderate derangement of nutritional status.

Results

The mean SDS values of Xc, PA, and D significantly improved ( p = 0.05, p = 0.001, p = 0.02) during the first 6 months of PD and remained almost stable during the following months. The SDS values of the anthropometric indices were less compromised than those of the BIA-derived indices, particularly at the start of dialysis. By 6 months, the percentages of children with values of BIA and anthropometric indices below the 3rd percentile had decreased. The percentages of patients with moderate and severe derangement of BIA and anthropometric indices remained substantially unchanged after 12 months. However, at 24 months, the percentage of patients with moderate derangement of BIA indices increased. All these findings were confirmed by the nutritional score system.

Conclusion

BIA is more sensitive than anthropometry in detecting alterations in body composition of children on PD. The prevalence of malnutrition, high at the commencement of PD, decreases during the first year of treatment but not over the long term.

Prescription and Assessment of Tidal Peritoneal Dialysis Delivery with a Specific Equilibration Test

Objective

To propose a simplified equilibration test specific for tidal peritoneal dialysis (TPD) that will overcome the inconveniences of the measurement of TPD peritoneal solute clearances through whole dialysate collection. This will enable the prediction of peritoneal creatinine and urea clearances, the suitability of patients for TPD, and routine assessment of TPD delivery.

Design

In a prospective study, patients had a standardized TPD run, and dialysate-to-plasma (DIP) ratios for creatinine and urea were calculated at various TPD and peritoneal equilibration test (PET) time points and on total TPD dialysate. Solute clearances were estimated and measured, and correlation coefficients were obtained among all these variables.

Setting

Dialysis unit of a pediatric nephrology department and patients’ homes.

Patients

Eleven pediatric patients with end-stage renal disease in stable clinical conditions treated with TPD.

Interventions

Dialysate and blood sample collections.

Main Outcome Measures

DIP ratios for creatinine and urea at the fifth and seventh TPD exchanges, at 15–,30–,60, and 120-minute PETtimes, and on total TPD dialysate and TPD peritoneal creatinine and urea clearances.

Results

Correlation coefficients between PET -derived and total TPD dialysate-derived DIP ratios, and those between PET -derived and measured creatinine and urea clearances were more significant at the 120-minute PET time point compared with the other PET time points. Best correlations were obtained at the fifth and seventh TPD exchanges. DIP ratios for creatinine and urea of the fifth and seventh TPD exchanges correlated significantly with the DIP ratios calculated from total TPD dialysate. A significant correlation was also found between peritoneal creatinine and urea clearances on total dialysate volume (measured clearances) and those derived from the dialysate collection of the fifth and seventh TPD exchanges (estimated clearances) -that based on the seventh exchange being slightly more significant. Moreover, the estimated clearances derived from the seventh exchange were within 10% of the measured value in 90.9% of patients both for creatinine and urea.

Conclusion

The significant correlation between measured and estimated peritoneal creatinine and urea clearances and the low percentage of underestimates of measured clearances obtained using the seventh TPD exchange-derived indices confirm the accuracy of the DIP ratios for creatinine and urea derived from any exchange after the fifth (preferably the seventh) of a standardized TPD run in estimating peritoneal creatinine and urea clearances. This method could represent a simple and accurate means for prescribing TPD and routinely assessing TPD delivery.

Evaluation of the Peritoneal Equilibration Test in Children on Chronic Peritoneal Dialysis

The peritoneal equilibration test (PET) is routinely performed in adults treated with chronic peritoneal dialysis to assess the peritoneal transport rate and to optimize treatment prescription. Only a few and not well-standardized studies on the PET have been reported in children. Twenty-six PETs were performed In 16 children, mean age 10.9±4.9 years, mean body weight (BW) 26.8±11.9 kg, treated with nightly intermittent peritoneal dialysis (NIPD). The PET was performed according to Twardowski. Forty mL/kg BW of 2.27% glucose solution were Infused at a rate of 10 mL/kg BW every 2 minutes. In the simplified test, dialysate samples were taken at dwell times 0, 2 and 4 hours for glucose and creatinine. A blood sample was taken after a 2-hour dwell time for the same parameters. The standard PET (8 patients) consisted of dialysate samples at 0, 15, 30, 60, 120, and 240 minutes and blood samples at 0 and 240 minutes. Mean DIP ratio for corrected creatinine and DIDo ratio for glucose at 2 hours were 51.6±11.6 and 50.4±9, respectively; at 4 hours 69.6± 12 and 34.4±9.8, respectively.

There was good correlation between DIP creatinine and DIDo glucose at 4 hours (p<0.0001). Patients were classified as high (3 cases), high-average (5), low-average (6), and low (2) transporters. A statistically significant difference was found between the curves obtained by the simplified PET and those of the standard PET In the first hour (r=0.66; p<0.05).

In conclusion, the PET, modified for use in children, gave reliable and reproducible results. Mean values of DIP creatinine for children were higher and DIDo glucose lower than those of adults as reported by Twardowskl. A consistent percentage of children had, nevertheless, a low-average or low transport rate. Standard PET is required in case of automated peritoneal dialysis prescription.

A Novel Objective Nutritional Score for Children on Chronic Peritoneal Dialysis

Objectives

To establish a novel nutritional score based on a series of objective parameters capable of detecting protein-calorie malnutrition in children being treated with chronic peritoneal dialysis (CPD), to test the score in a healthy pediatric population, and to apply it to children on CPD to evaluate their nutritional status.

Study Population

264 healthy school children (mean age 8.69 ± 3.26 years, range 3.05 – 14.98 years) and 29 patients treated with CPD for 1.75 ± 1.02 years (mean age 10.54 ± 6.28 years, range 2.8 – 15.24 years).

Methods

Nutritional status was evaluated by means of three sets of measurements: anthropometric (A1 and A2) and bioimpedance analysis (BIA) measurements. Anthropometry included two sets of measures: set A1 consisted of height (H), weight (W), and body mass index (BMI); set A2 consisted of midarm muscle circumference (MAMC), arm muscle area (AMA), and arm fat area (AFA). The BIA measurements included reactance, phase angle, and distance. All parameters are expressed as standard deviation scores (SDS). Tanner's, Rolland–Cachera's, and Frisancho's data were used as references for H, W, BMI, MAMC, AMA, and AFA; personal data obtained from 551 healthy boys and girls were used for the BIA indices. The nine anthropometry and BIA parameters were given scores of 1 to 5: 5 = > 0 SDS, 4 = ≤ 0 and > –1 SDS, 3 = ≤ –1 and > –2 SDS, 2 = ≤ –2 and > –3 SDS, and 1 = ≤ –3 SDS. Average scores were established for each of A1, A2, and BIA, and then summed to obtain the anthropometry–BIA nutrition (ABN) score. To establish the cutoff value between normal nutritional status and malnutrition, the method was first applied to the 264 healthy children; distribution percentiles were calculated for each area score and the ABN score. The ABN score corresponding to the 3rd percentile was considered the limit of normality and then applied three times to the 29 children on CPD, for a total of 87 nutritional assessments.

Results

The score corresponding to the 3rd percentile in the population of healthy children was 10.33. Among the CPD-treated children, 41.4% of the ABN scores were higher than 10.33 (indicating a state of normal nutrition) and 58.6% were lower (indicating various degrees of malnutrition). Severe malnutrition was found in only 1.1% of the cases. The values of all nine A1, A2, and BIA parameters, as well as serum albumin levels, were significantly higher in patients with an ABN score > 10.33 than in those with a score < 10.33.

Conclusion

The ABN score is a simple and objective method of assessing, in clinical practice, the nutritional status of children on CPD.

Complications Linked to Chronic Peritoneal Dialysis in Children after Kidney Transplantation: Experience of the Italian Registry of Pediatric Chronic Peritoneal Dialysis

Our objective was to evaluate the infectious complications of the post-transplant period attributable to the persistence of catheter and other complications when chronic peritoneal dialysis (CPD) was performed posttransplantation. The design was a retrospective study, and the setting was an Italian registry of pediatric chronic peritoneal dialysis.

There were 86 pediatric renal transplants (9/86 from living related donors, 2/86 simultaneous liver and kidney transplantation for oxalosis). Six of 86 transplants were lost at follow-up. Mean age of the children (n = 80) at transplantation was 9.3 years (range:1.7–21 years). They had been on CPD for a mean period of 1.7 years (range: 0.2 -4.6 years). During CPD, 67 peritonitis episodes (80% related to exit-site and/or tunnel infections) were observed, with an incidence of peritonitis of one episode per 16 months CPD. The mean safe interval of peritonitis and/ or exit-site or tunnel infection was 208 days (range: 36 1897 days). The mean time of catheter removal was 80.3 days (range: 0 216 days) post-transplantation.

During the first month post-transplantation, one episode of peritonitis secondary to a sepsis occurred in one child. No other episodes of peritonitis or exit-site and/or tunnel infections were observed. Two of 80 children returned to CPD (at four and at 12 months, respectively) because of persistent allograft failure. Furthermore, 12 patients were on CPD because of temporary graft failure. In all these patients the pretransplant peritoneal dialysis (PD) catheter was utilized, with no complications.

These data show that the persistence of the PD catheter after kidney transplantation has produced no infections or other complications. What is more, the catheter was safely utilized during acute rejection or primary allograft nonfunction.

Persistent Abnormalities of Fatty Acids Profile in Children With Idiopathic Nephrotic Syndrome in Stable Remission

Steroid-sensitive nephrotic syndrome is an immunological disorder mediated by still poorly defined circulating factor(s) that target the podocyte and damage the filtration barrier. Fatty acids (FA) have several biological roles and, in particular, are strictly involved in cell to cell communication, inflammatory processes and regulation of lymphocyte pools. Studies of FAs during INS have been mainly focused on biochemical changes during the phase of proteinuria; while no information is available about FA profile in patients with idiopathic nephrotic syndrome (INS) on stable remission. Aim of this study is to assess differences in blood FA profile between pediatric patients with INS during the phase of stable remission. Blood fatty acid profile of 47 pediatric patients on stable remission and 47 matched healthy controls were evaluated with gas chromatography. Patients with INS on stable remission had significantly higher levels of PUFA and omega-6 than controls (40.17 vs. 37.91% and 36.95 vs. 34.79%), lower levels of SFA and MUFA. Considering the single fatty acids, levels of omega-6 18:2n6 linoleic acid and omega-6 20:4n6 arachidonic acid were significantly higher in patients with INS than in controls (23.01 vs. 21.55%, p-value 0.003 and 10.37 vs. 9.65%, p-value 0.01). Moreover, patients with INS showed lower levels of SFA 14:0 (0.74 vs. 0.92%) and 18:0 (10.74 vs. 11.74%) and MUFA 18:1n9 oleic acid (18.50 vs. 19.83%). To the best of our knowledge this is the first study assessing FAs profile in children with INS in stable remission. In a population of 47 patients, we were able to demonstrate a higher blood level of linoleic and arachidonic acid, and consequently of omega-6 and PUFA, compared to controls. Persistently higher than normal levels of either linoleic or arachidonic acid, could be viewed as candidate biomarker for a state of risk of relapse in children with idiopathic nephrotic syndrome.

Post-transplant recurrence of steroid resistant nephrotic syndrome in children: the Italian experience

Background

Steroid resistant nephrotic syndrome (SRNS) is a frequent cause of end stage renal disease in children and post-transplant disease recurrence is a major cause of graft loss.

Methods

We identified all children with SRNS who underwent renal transplantation in Italy, between 2005 and 2017. Data were retrospectively collected for the presence of a causative gene mutation, sex, histology, duration of pre-transplant dialysis, age at onset and transplant, HLA matching, recurrence, therapy for recurrence, and graft survival.

Results

101 patients underwent a first and 22 a second renal transplant. After a median follow-up of 58.5 months, the disease recurred on the first renal transplant in 53.3% of patients with a non-genetic and none with a genetic SRNS. Age at transplant > 9 years and the presence of at least one HLA-AB match were independent risk factors for recurrence. Duration of dialysis was longer in children with relapse, but did not reach statistical significance. Overall, 24% of patients lost the first graft, with recurrence representing the commonest cause. Among 22 patients who underwent a second transplant, 5 suffered of SRNS recurrence. SRNS relapsed in 5/9 (55%) patients with disease recurrence in their first transplant and 2 of them lost the second graft.

Conclusions

Absence of a causative mutation represents the major risk factor for post-transplant recurrence in children with SRNS, while transplant can be curative in genetic SRNS. A prolonged time spent on dialysis before transplantation has no protective effect on the risk of relapse and should not be encouraged. Retransplantation represents a second chance after graft loss for recurrence.

MIF plasma level as a possible tool to predict steroid responsiveness in children with idiopathic nephrotic syndrome

PURPOSE

Idiopathic nephrotic syndrome (INS) is the most frequent form of childhood nephrotic syndrome. Steroids represent the best therapeutic option; however, inter-individual differences in their efficacy and side effects have been reported. To date, there is no way to predict patients' resistance and/or dependence. Alterations in the cytokine profile of INS patients might contribute to proteinuria and glomerular damage and affect drug sensitivity.

METHODS

The cytokine plasma levels were measured in 21 INS children at diagnosis to investigate the association among cytokines pattern and clinical response. Patients were selected on the basis of their clinical response: 7 steroid sensitive (SS), 7 dependent (SD), and 7 resistant (SR). Significant results were then analyzed in 41 additional pediatric INS patients.

RESULTS

Within the 48 cytokines analyzed, macrophage migration inhibitory factor (MIF) was a good predictor of steroid response. Indeed, SR patients showed significantly higher MIF plasma levels compared with all others (p = 0.022; OR = 4.3, 95%CI = 1.2-25.4): a cutoff concentration of MIF > 501 pg/ml significantly discriminated SR patients (sensitivity = 85.7%, specificity = 71.4%). On the contrary, SD patients showed lower MIF plasma levels compared with others (p = 0.010; OR = 0.12, 95%CI = 9.2 × 10^-3-6.7 × 10^-1). Significant results were confirmed in the entire cohort.

CONCLUSIONS

Our comprehensive cytokine analysis indicates that assessing MIF plasma levels at diagnosis could predict response to glucocorticoids in children with INS.

The Italian Society for Pediatric Nephrology (SINePe) consensus document on the management of nephrotic syndrome in children: Part I - Diagnosis and treatment of the first episode and the first relapse

This consensus document is aimed at providing an updated, multidisciplinary overview on the diagnosis and treatment of pediatric nephrotic syndrome (NS) at first presentation. It is the first consensus document of its kind to be produced by all the pediatric nephrology centres in Italy, in line with what is already present in other countries such as France, Germany and the USA. It is based on the current knowledge surrounding the symptomatic and steroid treatment of NS, with a view to providing the basis for a separate consensus document on the treatment of relapses. NS is one of the most common pediatric glomerular diseases, with an incidence of around 2-7 cases per 100000 children per year. Corticosteroids are the mainstay of treatment, but the optimal therapeutic regimen for managing childhood idiopathic NS is still under debate. In Italy, shared treatment guidelines were lacking and, consequently, the choice of steroid regimen was based on the clinical expertise of each individual unit. On the basis of the 2015 Cochrane systematic review, KDIGO Guidelines and more recent data from the literature, this working group, with the contribution of all the pediatric nephrology centres in Italy and on the behalf of the Italian Society of Pediatric Nephrology, has produced a shared steroid protocol that will be useful for National Health System hospitals and pediatricians. Investigations at initial presentation and the principal causes of NS to be screened are suggested. In the early phase of the disease, symptomatic treatment is also important as many severe complications can occur which are either directly related to the pathophysiology of the underlying NS or to the steroid treatment itself. To date, very few studies have been published on the prophylaxis and treatment of these early complications, while recommendations are either lacking or conflicting. This consensus provides indications for the prevention, early recognition and treatment of these complications (management of edema and hypovolemia, therapy and prophylaxis of infections and thromboembolic events). Finally, recommendations about the clinical definition of steroid resistance and its initial diagnostic management, as well as indications for renal biopsy are provided.

Renal transplantation in sensitized children and young adults: a nationwide approach

Background

High levels of preformed anti-HLA antibodies dramatically diminish renal transplant outcomes. Most desensitization programmes guarantee good intermediate outcomes but quite disappointing long-term prognosis. The search for a fully compatible kidney increases time on the waiting list.

Methods

In February 2011, a nationwide hyperimmune programme (NHP) was begun in Italy: all available kidneys are primarily proposed to highly sensitized patients with a panel reactive antibody above 80%. In this manuscript, we evaluate the outcome of paediatric patients transplanted with this approach.

Results

Twenty-one patients were transplanted. Complete data are available for 20 patients. Mean age at transplantation was 14.5 years [standard deviation (SD) ± 5.5)]. Mean time on the waiting list was 29.3 months (SD ± 27.5). Median follow-up was 29.2 months (range: 11.2-59.3). The average number of HLA mismatches in these patients was 2.3 versus 3.7 in 48 standard patients transplanted in the same period (P < 0.001). Only one graft was lost. Two cases of humoral rejection occurred and were successfully treated. No cellular rejection was reported. Median creatinine clearance was 84, 88, 77 and 77 mL/min/1.73 m 2 respectively 1, 6, 12 and 24 months after transplant.

Conclusions

Transplantation of sensitized patients avoiding prohibited antigens is feasible, at least in a selected cohort of patients. In order to be able to further improve this approach, which in our opinion is very successful, it would be necessary to expand the donor pool, possibly increasing the number of countries participating in the programme. In this series, time on the waiting list did not increase significantly. This allocation policy should ideally lead to an outcome comparable to that expected in standard patients, which is particularly desirable in young patients who have the longest life expectancy. Since long-term results of desensitization programmes are not (yet) convincing, we suggest that these programmes should be reserved for selected cases where compatible organs cannot be found within a reasonable time span.

SXR rs3842689: a prognostic factor for steroid sensitivity or resistance in pediatric idiopathic nephrotic syndrome

AIM

of the study was to analyse the impact of SXR rs3842689 polymorphism on the response to corticosteroids in pediatric idiopathic nephrotic syndrome.

PATIENTS & METHODS

66 children (56 steroid-sensitive, ten steroid-resistant) were studied for SXR gene polymorphism distribution.

RESULTS

Steroid sensitive patients accounted for 96% of cases with In/In polymorphism, but only for 53% of cases with Del/Del polymorphism At odds ratio analysis, Del/Del represented a clear risk factor of steroid resistance (OR: 20.57; p = 0.009), while In/In was a favourable prognostic factor of steroid sensitivity.

CONCLUSION

The analysis of SXR polymorphism is a promising tool to predict both the favourable response to corticosteroids and the risk of developing steroid resistance.

In vitro sensitivity to methyl-prednisolone is associated with clinical response in pediatric idiopathic nephrotic syndrome

The aim of this study was to evaluate the in vitro steroid sensitivity as a predictor of clinical response to glucocorticoids in childhood idiopathic nephrotic syndrome (INS). Seventy-four patients (median age 4.33, interquartile range [IQR] 2.82-7.23; 63.5% male) were enrolled in a prospective multicenter study: in vitro steroid inhibition of patients' peripheral blood mononuclear cell proliferation was evaluated by [methyl-(3) H] thymidine incorporation assay at disease onset (T0) and after 4 weeks (T4) of treatment. Steroid dependence was associated with increased in vitro sensitivity at T4 assessed both as drug concentration inducing 50% of inhibition (IC50 ; odds ratio [OR] = 0.48, 95% confidence interval [CI] = 0.24-0.85; P = 0.0094) and maximum inhibition at the highest drug concentration (Imax ; OR = 1.13, 95% CI = 1.02-1.31; P = 0.017). IC50 > 4.4 nM and Imax < 92% at T4 were good predictors for optimal clinical response. These results suggest that this test may be useful for predicting the response to glucocorticoid therapy in pediatric INS.

Human herpesvirus-6 and polyomaviruses DNAemia in children and young adult patients after kidney transplantation

Aims: Human herpesvirus-6 (HHV-6) and polyomaviruses (HPyV) establish latency and reactivate in immunocompromised hosts. The prevalence of their infections was investigated in pediatric and young adult kidney transplant recipients. Materials & methods: Blood was obtained from 83 patients. Quantitative real-time polymerase chain reactions were conducted to quantify HHV-6 and HPyV loads; nested PCR and reverse transcriptase-PCR assays were conducted to differentiate HHV-6A from 6B and to evaluate the presence of transcripts. Results: HHV-6 and HPyV DNAemia were detected in 19.3 and 18.1% patients, respectively. No association between HHV-6 and HPyV DNA presence, age of patients and time from transplant was observed. Conclusion: HHV-6 infection in immunosuppression setting was as common as those of HPyVs that are commonly recognized as opportunistic agents.

An updated Italian normative dataset for the Stroop color word test (SCWT)

The Stroop color and word test (SCWT) is widely used to evaluate attention, information processing speed, selective attention, and cognitive flexibility. Normative values for the Italian population are available only for selected age groups, or for the short version of the test. The aim of this study was to provide updated normal values for the full version, balancing groups across gender, age decades, and education. Two kinds of indexes were derived from the performance of 192 normal subjects, divided by decade (from 20 to 90) and level of education (4 levels: 3-5; 6-8; 9-13; >13 years). They were (i) the correct answers achieved for each table in the first 30 s (word items, WI; color items, CI; color word items, CWI) and (ii) the total time required for reading the three tables (word time, WT; color time, CT; color word time, CWT). For each index, the regression model was evaluated using age, education, and gender as independent variables. The normative data were then computed following the equivalent scores method. In the regression model, age and education significantly influenced the performance in each of the 6 indexes, whereas gender had no significant effect. This study confirms the effect of age and education on the main indexes of the Stroop test and provides updated normative data for an Italian healthy population, well balanced across age, education, and gender. It will be useful to Italian researchers studying attentional functions in health and disease.

Relationship between mRNA expression levels of CYP3A4, CYP3A5 and SXR in peripheral mononuclear blood cells and aging in young kidney transplant recipients under tacrolimus treatment

Aim: The activity of several key enzymes involved in the metabolism of many drugs is subject to change closely related to the age of patients. This possibility must also be considered in the case of tacrolimus, the most important calcineurins inhibitor, which is widely used in pediatric kidney transplantation. As well as in the liver and intestine, some of the enzymes involved in the metabolism of tacrolimus were also isolated in the peripheral blood mononuclear cells (PBMCs), where also appear to play an important regulatory action. Therefore, the influence of some external factors on the expression of specific mRNA can be determined noninvasively. Patients & methods: The correlation between the levels of mRNA specific for key enzymes SXR, CYP3A and ABCB1 involved in the metabolism of tacrolimus was evaluated in PBMCs obtained from a selected population of 29 young kidney transplant recipients. A possible correlation between the expression of these specific mRNAs and tacrolimus pharmacokinetics was also investigated. Results: The patients’ age and their blood concentrations of SXR mRNA were directly correlated with the expression of CYP3A4, CYP3A5 mRNAs, but not of ABCB1 mRNA in the PBMCs. tacrolimus-normalized daily dose was strongly correlated with patient's age and multivariable regression indicates the CYP3A4-specific mRNA as the sole independent variable influencing tacrolimus concentration-to-dose ratio. Conclusion: Aging and SXR mRNA significantly affect the expression of CYP3A4- and CYP3A5-specific mRNA as measured by their concentration in PBMC.

Original submitted 17 November 2014; Revision submitted 6 February 2015

Plasma-exchange in pediatric patients: a single-center experience

BACKGROUND

Plasma-exchange (PEX) has been well described in pediatrics, but most of the current indications are derived from adult experience. Aim of the study was to review the PEX treatments in our Unit over a six-year period.

METHODS

Three hundred and seventy-seven PEX sessions were performed in 38 patients (median age 12.1 years, range 0.6-20.5). Double-needle and single-needle PEX combined with hemodialysis and PEX combined with ultrafiltration were performed in 9, 1 and 3 patients respectively. The most common indications to PEX were atypical hemolytic uremic syndrome (aHUS, 9 patients), focal segmental glomerulosclerosis (FSGS, 9 cases), antibody mediated rejection (AMR) in renal transplant (rTx) recipients (8 patients) and hyperimmunization in patients waiting for rTx (4 cases).

RESULTS

We treated five patients with aHUS on native kidneys with PEX only, with complete remission in 4/6 recurrences; PEX was also successfully used to prevent HUS relapse in three patients undergoing rTx. Only one partial remission was obtained in four patients with FSGS on native kidneys, by means of treatment protocols based on PEX and immunosuppressants; conversely, a partial remission was observed in 6/6 patients with recurrence of FSGS on rTx. Immunosuppressive protocols combined with PEX proved useful in sensitized cadaveric rTx recipients (2/4 successfully transplanted), but failed in 6 patients with chronic AMR. As regards complications, two severe adverse reactions occurred: an anaphylactic shock after the use of albumin and an abdominal hemorrhage.

CONCLUSIONS

PEX is a relatively safe procedure in children. Pediatric patients with aHUS, recurrent FSGS and sensitized rTx recipients seem to benefit from treatment strategies including PEX.

Three-yr safety and efficacy of everolimus and low-dose cyclosporine in de novo pediatric kidney transplant patients

The three yr results of a multicenter trial in de novo pediatric KT treated with a proliferative signal inhibitor and low dose CNI are presented. Thirty-seven children (9.1 ± 5 yr old) received basiliximab, cyclosporine A (CyA C2:1400 ng/mL), (MMF C0:1.5-3 μg/mL), and prednisone. Three wk later everolimus was started (C0:5-10 ng/mL), CyA was reduced (C2:600 ng/mL after 90 days 300 ng/mL), and MMF discontinued. During the three-yr period patient and graft survivals were 96%. One patient died for causes unrelated to the immunosuppression. Cumulative acute rejection rate including protocol and indication biopsies was 21.9%. None of the patients had signs of chronic humoral rejection. Incidence of dnDSA was 5%, 11%, and 22% at one, two, and three yr post-transplant, respectively. Mean glomerular filtration rate measured at one yr and three yr post-transplant was 105.5 ± 31 and 110.7 ± 27 mL/min/1.73 m(2), respectively. A growth velocity of 7.7 ± 6.7 cm/yr was achieved with positive catch-up growth. No malignancy or post-transplant lymphoproliferative diseases were diagnosed. In conclusion, the treatment based on basiliximab induction, everolimus, low-dose cyclosporine, and low-dose prednisone leads to good long-term efficacy in de novo pediatric KT recipients.

Allogeneic mesenchymal stem cell infusion for the stabilization of focal segmental glomerulosclerosis

Focal segmental glomerulosclerosis (FSGS) is the most frequent acquired renal condition resulting in end stage kidney disease in children. We describe a cell therapy treatment with human allogeneic bone marrow mesenchymal stem cells (MSC) in a 13-year-old patient developing recurrent FSGS after renal transplantation, which was not responding to conventional therapy. This treatment relied on the following measurements:clinical and laboratory evaluation of renal function, proteome array, biopsy, short tandem repeat assay. Before MSC treatment, the patient needed weekly plasmapheresis to achieve proteinuria-to-creatininuria ratio below 5. After three MSC infusions without adverse events, the patient has a stable renal function and the proteinuria target was reached without plasmapheresis. In addition, some circulating inflammatory factors decreased and their levels were still low after one year. This is the first report of an MSC treatment in an FSGS patient. Even though different factors may have contributed to the clinical results, after MSC infusion a stable reduction in the serum level of several inflammatory factors has been registered and the patient does not need anymore plasmapheresis to keep proteinuria under control. In addition, this encouraging single case let us identify some putative efficacy biomarkers that could be of clinical interest in chronic kidney diseases.

Long-term effects of ABCB1 and SXR SNPs on the systemic exposure to cyclosporine in pediatric kidney transplant patients

Aim: Cyclosporine is characterized by a wide interindividual variability in its pharmacokinetics. The objective of this study was to evaluate the effects of ABCB1 and SXR SNPs on cyclosporine exposure in a group of kidney transplant patients followed up from childhood to adulthood. Patients & methods: Recipients were genotyped for ABCB1 C1236T, G2677T/A and C3435T, and for SXR RS3842689 and A7635G. Dose-adjusted trough levels and weight-adjusted daily doses were compared among patients according to allelic status by a generalized estimation equation approach that allows longitudinal data analyses. Results: A genotype-dependent effect was found in all ABCB1 genotypes and in one of the SXR SNPs. This effect was particularly evident for the TT genotype of the ABCB1 G2677T/A SNP, the TT genotype of the ABCB1 C3435T SNP and for heterozygotes of the deletion of 6 bp in the promoter region of SXR. Conclusion: The presence of specific ABCB1 and SXR SNPs could significantly affect cyclosporine exposure during a kidney transplant patient’s development from childhood to adulthood in a time-dependent fashion.

Original submitted 3 May 2013; Revision submitted 25 July 2013

Posttransplant de novo donor-specific hla antibodies identify pediatric kidney recipients at risk for late antibody-mediated rejection

The emerging role of humoral immunity in the pathogenesis of chronic allograft damage has prompted research aimed at assessing the role of anti-HLA antibody (Ab) monitoring as a tool to predict allograft outcome. Data on the natural history of allografts in children developing de novo Ab after transplantation are limited. Utilizing sera collected pretransplant, and serially posttransplant, we retrospectively evaluated 82 consecutive primary pediatric kidney recipients, without pretransplant donor-specific antibodies (DSA), for de novo Ab occurrence, and compared results with clinical-pathologic data. At 4.3-year follow up, 19 patients (23%) developed de novo DSA whereas 24 had de novo non-DSA (NDSA, 29%). DSA appeared at a median time of 24 months after transplantation and were mostly directed to HLA-DQ antigens. Among the 82 patients, eight developed late/chronic active C4d+ antibody-mediated rejection (AMR), and four C4d-negative AMR. Late AMR correlated with DSA (p < 0.01), whose development preceded AMR by 1-year median time. Patients with DSA had a median serum creatinine of 1.44 mg/dL at follow up, significantly higher than NDSA and Ab-negative patients (p < 0.005). In our pediatric cohort, DSA identify patients at risk of renal dysfunction, AMR and graft loss; treatment started at Ab emergence might prevent AMR occurrence and/or progression to graft failure.

Investigation of polyomaviruses replication in pediatric patients with nephropathy receiving rituximab

Rituximab is a chimeric monoclonal antibody reacting with the CD20 antigen on B cells. It has been proposed as treatment for the idiopathic nephrotic syndrome, recurrent idiopathic nephropathy, and focal segmental glomerulosclerosis refractory to steroids. Rituximab influences T-cell immunity and may predispose the patients to opportunistic infections, such as progressive multifocal leukoencephalopathy caused by the polyomavirus JC (JCV). The risk of latent viruses infections/reactivations in pediatric patients receiving monoclonal antibodies is not well known yet. In this longitudinal 6-month study, the effects of rituximab on JCV and BK virus (BKV) replication have been investigated. Blood, serum, and urine samples have been collected monthly from 11 pediatric patients (mean age: 11 years) with the idiopathic nephrotic syndrome and recurrent idiopathic nephropathy, under rituximab therapy. JCV and BKV real-time PCRs and sequencing of the viral protein 1 and the non-coding control region have been conducted. The same investigations have been undertaken on samples collected from eight pediatric patients (controls, mean age: 6 years), with idiopathic nephrotic syndrome or focal segmental glomerulosclerosis, treated with conventional chemotherapy. JCV was detected in the urine of one patient (9%), and one control (12.5%); BKV was found in the urine of 7/11 patients (63.6%) and 2/8 controls (25%) and in blood samples from four patients. No significant difference was found in the mean viral loads and in the viral molecular characterizations between the two groups. The polyomaviruses replication was not associated with rituximab therapy in children.

The potential of steroids and xenobiotic receptor polymorphisms in forecasting cyclosporine pharmacokinetic variability in young kidney transplant recipients

The steroids and xenobiotics receptor (SXR) up-regulates the expression and the synthesis of key enzymes in CyA metabolism. In this study, we examined the possible interactions between CyA exposure and SXR polymorphisms during the first year after renal transplantation. The study involved 66 pediatric renal transplant recipients (25 women and 41 men, mean age 13.9 ± 7.4 yr). All patients were genotyped for two sequence variations in the NR1I2 gene: g.-205_-200delGAGAAG and 7635 A>G. CyA trough levels and CyA weight-adjusted daily dose were recorded at 30, 90, 180, and 360 days after transplantation and compared between the different genotypes. A third newly discovered SXR polymorphism was characterized and also included in the study. CyA trough levels and CyA weight-adjusted daily dose were comparable on four time points throughout the first year post-transplant in all three groups. GEE showed a significant reduction in weight-adjusted CyA daily dose in patients carrying the deletion of 6 bp in SXR with a significant group-by-time effect that persisted also when analysis was corrected for age, prednisone dose, and acute rejection episodes. In our group of patients, only the g.-205_-200delGAGAAG SXR polymorphism was able to influence the metabolism of CyA continuously, during the first year after transplantation.

Is Venice an ideal habitat for Legionella pneumophila?

INTRODUCTION

Legionella bacterium manifests itself in Legionnaire's disease and Pontiac fever, it is mainly found and transmitted by aerosol produced in cooling towers, water distribution plants and medical equipment, and it affects mainly elder persons in poor health.

METHODS

The population of Venice Local Health Unit was divided in two areas of study and the incidence of legionellosis in residents of Venice historical centre (Distretto Sanitario 1) and in residents of the mainland and coastal areas (Distretti Sanitari 2, 3, 4) was calculated. The cases were those notified to the Public Health Unit by law, and the population of residents was that of the eligible for health care in the archives of the Local Health Unit. Only cases of legionellosis in residents who had not travelled in the 10 days previous of the onset of disease, and not related to nosocomial clusters were considered. The standardized incidence ratio was then calculated and confidence interval were defined by Poisson distribution.

RESULTS

Given the population of the two areas, 59801 in Distretto Sanitario 1 and 237555 in Distretti 2, 3, 4, the raw incidence of disease is respectively 87 per 100000 and 20 per 100000 in time 2002-2010. The standardized incidence ratio for the population of Distretto Sanitario 1 vs the remaining population is 4.3.

DISCUSSION

The difference in risk of getting the disease in this two residential areas geographically very close, is probably related to the different buildings' characteristics, old and difficult to maintain in Venice historical centre.

Rituximab in children with resistant idiopathic nephrotic syndrome

Idiopathic nephrotic syndrome resistant to standard treatments remains a therapeutic dilemma in pediatric nephrology. To test whether the anti-CD20 monoclonal antibody rituximab may benefit these patients, we conducted an open-label, randomized, controlled trial in 31 children with idiopathic nephrotic syndrome unresponsive to the combination of calcineurin inhibitors and prednisone. All children continued prednisone and calcineurin inhibitors at the doses prescribed before enrollment, and one treatment group received two doses of rituximab (375 mg/m(2) intravenously) as add-on therapy. The mean age was 8 years (range, 2-16 years). Rituximab did not reduce proteinuria at 3 months (change, -12% [95% confidence interval, -73% to 110%]; P=0.77 in analysis of covariance model adjusted for baseline proteinuria). Additional adjustment for previous remission and interaction terms (treatment by baseline proteinuria and treatment by previous remission) did not change the results. In conclusion, these data do not support the addition of rituximab to prednisone and calcineurin inhibitors in children with resistant idiopathic nephrotic syndrome.

Association between CYP3A5 polymorphisms and blood pressure in kidney transplant recipients receiving calcineurin inhibitors

Abstract Renal cytochrome P450 3A5 (CYP3A5) has been associated with blood pressure (BP) control in humans. We investigated whether CYP3A5 polymorphisms are associated with post- transplant hypertension in a selected population of kidney recipients receiving calcineurin inhibitors. Ninety-two kidney transplant recipients receiving cyclosporine (CyA) or tacrolimus (Tac) were genotyped for CYP3A5 polymorphisms, and the association between the CYP3A5 alleles (*1,*3) and hypertension on post-operative day (POD) 6 and POD 180 was verified, with multiple regression being used to identify the putative co-variates that may predict the extent and severity of hypertension in transplant recipients at different post-transplant times. The CYP3A5*1 carriers had higher systolic (SBP) and diastolic blood pressure (DBP) in both the immediate and delayed post-transplant period when adjusted for anti-hypertensive medication (POD 6: SBP = 161 ± 23 vs. 140 ± 23 mmHg; DBP = 120 ± 15 vs. 87 ± 14 mmHg, p < 0.05. POD 180: SBP = 136 ± 16 vs. 129 ± 14 mmHg; DBP = 89 ± 15 vs. 80 ± 15 mmHg, p < 0.05). The severity of hypertension between the CYP3A5*1 carriers and noncarriers on POD 6 was documented by the significantly different distribution of hypertension classes, but this was not confirmed on POD 180. The CYP3A5 genotype was the only independent variable affecting mean arterial pressure. The results of this study show that CYP3A5 polymorphisms are associated with the severity and degree of hypertension in kidney transplant recipients receiving calcineurin inhibitors regardless of the time of recording. However, the role of concomitant medications such as steroids with strong CYP3A5 inducing activity, should be taken into account.

Involving patients who attempt suicide in suicide prevention: a focus groups study

The aim of this study is to gain insight into the individual experiences of patients who attempt suicide in order to better understand the reasons for and emotions behind a suicide attempt, thus also gaining insight, through the patients' own input, into the risk and protective factors which might influence possible repeat attempts and the attitude towards the assistance they receive. Two focus groups were conducted involving 17 participants, all hospitalized at the time of research for attempting suicide. The patients proved themselves competent, even expert in indicating reasons for, risk factors of and prevention strategies for suicide. The main findings suggest that the relational factor represents a key point both as a trigger for the suicide attempt and for promoting the communication of the intent or for preventing a repeat suicide attempt, as interpersonal relationships and an empathic environment were, in essence, what was perceived as therapeutic and protective and enabled the expression of thoughts and self-understanding. Accordingly psychotherapy, non-specific relationship 'monitoring' after discharge and tutored self-help groups have been suggested. Feasibility and implementing methods as well as the role of the nurse for such interventions were discussed.

Schizophrenia trial participation: perceived inclusion barriers and beliefs about antipsychotics

BACKGROUND

Patient recruitment is the universal rate-limiting factor for randomized controlled trials (RCTs) in all medical specialties. This study examined the opinions on perceived inclusion barriers and beliefs about antipsychotics of a group of psychiatrists participating in a pragmatic RCT on antipsychotic drugs in schizophrenia (the GiSAS trial).

METHODS

A survey of all clinicians working in the trial recruiting centers was performed exploring factors associated to the respondents' opinions.

RESULTS

Of 465 clinicians, 278 (59.8%) responded to the questionnaire. Respondents (n=278) were mainly influenced by clinical and trial-related barriers (89%). Factors such as work setting and antipsychotic prescription choices appeared to be related to perceived inclusion barriers. Most respondents believed in the superiority of SGAs (62.9%), one-third indicating drug company representatives as the most important source of information; this was related to further optimism towards SGAs.

CONCLUSIONS

Respondents were affected mainly by system-related barriers, whereas personal barriers were given less weight. The influence of industry-mediated information could have affected opinions on SGAs and the lack of uncertainty about antipsychotics attitudes towards trial participation.

Short-term effects of rituximab in children with steroid- and calcineurin-dependent nephrotic syndrome: a randomized controlled trial

BACKGROUND AND OBJECTIVES

Prednisone and calcineurin inhibitors are the mainstay therapy of idiopathic nephrotic syndrome (INS) in children. However, drug dependence and toxicity associated with protracted use are common. Case series suggest that the anti-CD20 monoclonal antibody rituximab (RTX) may maintain disease remission.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This open-label randomized controlled trial was powered to show that a strategy based on RTX and lower doses of prednisone and calcineurin inhibitors was noninferior to standard doses of these agents in maintaining 3-month proteinuria as low as baseline or up to 1 g/d greater (noninferiority margin). Participants were stratified by the presence of toxicity to prednisone/calcineurin inhibitors and centrally assigned to add RTX (Mabthera, 375 mg/m(2) intravenously) to lower doses of standard agents or to continue with current therapy alone. The risk of relapse was a secondary outcome.

RESULTS

Fifty-four children (mean age 11 ± 4 years) with INS dependent on prednisone and calcineurin inhibitors for >12 months were randomized. Three-month proteinuria was 70% lower in the RTX arm (95% confidence interval 35% to 86%) as compared with standard therapy arm (intention-to-treat); relapse rates were 18.5% (intervention) and 48.1% (standard arm) (P = 0.029). Probabilities of being drug-free at 3 months were 62.9% and 3.7%, respectively (P < 0.001); 50% of RTX cases were in stable remission without drugs after 9 months.

CONCLUSIONS

Rituximab and lower doses of prednisone and calcineurin inhibitors are noninferior to standard therapy in maintaining short-term remission in children with INS dependent on both drugs and allow their temporary withdrawal.

[Kidney transplant from living donors in children?]

A living-donor kidney transplant offers a child at the terminal stages of renal disease better functional recovery and quality of life than an organ from a deceased donor. Before starting the procedure for a living-donor transplant, however, it is necessary to establish if it is really safe. There are diseases, such as focal segmental glomerulosclerosis, atypical HUS and membranoproliferative glomerulonephritis with dense deposits, for which living donation is not recommended given the high incidence of recurrence of the disease but also the frequent loss of the graft. Regarding the selection of the donor, an increased risk of acute rejection has been reported for donors older than 60-65 years and a worsening of the renal outcome if the donor's weight is equal to or less than the recipient's. Finally, it is necessary to take into consideration that complications may arise in the donor both in the perioperative period and in the long term. In conclusion, kidney transplant from a living donor is a natural choice within the pediatric setting. The parents, usually young and highly motivated to donate, are the ideal donors. However, although the risks associated with donation are minimal, they are not totally absent, and consequently it is mandatory to follow standardized procedures according to the guidelines issued by the Centro Nazionale Trapianti.

Successful medical treatment of EBV smooth muscle tumor in a renal transplant recipient

EBV is associated with various malignancies in patients with acquired or induced immune impairment. EBV-SMT is very uncommon in immunocompromised patients, and a kidney localization has been described only anecdotally. We report the case of a 17-yr-old kidney transplant recipient diagnosed as having an EBV-SMT inside the renal graft, which was successfully managed by minimizing isolated immunosuppression.

The role of immunosuppression in malignancies among 351 pediatric renal transplant patients

The incidence of de novo malignancies over a 38 year experience in 351 children ranging in age from 2 to 18 years was investigated among subjects prescribed various immunosuppressive protocols. There were 14 children (3.98%) who showed de novo malignancies, namely, 4.86 cancers for every 1000 graft-function years (GFYs). Among patients who had grafts functioning for >10 years, 7.4% suffered from cancer. Nine patients survive without a recurrence at a mean of 12.5 +/- 6.6 years including 6 with graft function. Among group I who were treated with pre-calcineurin inhibitor (CNI) therapy 3 (3.8%) children (1 male and 2 females) developed a malignancy at a mean of 15.2 +/- 11.9 years posttransplant (range, 7-35), for 4.65 cancers every 1000 GFYs. Two of them survive with functioning grafts. Among group II, who were treated by CNIs there were 273 children including 24 retransplants. Group II showed 11 malignancies (4.0%), for 5.04 malignancies for every 1000 GFYs. The incidence of cancer was similar in the 2 groups, undergoing different immunosuppressive regimens; however, the malignancies in the CNI- group were more precocious, compared with those of the conventionally-treated cohort.

An open-label, randomized clinical trial assessing immunogenicity, safety and tolerability of pandemic influenza A/H1N1 MF59-adjuvanted vaccine administered sequentially or simultaneously with seasonal virosomal-adjuvanted influenza vaccine to paediatric kidney transplant recipients

Background. The aim of this study was to investigate the immunogenicity, safety and tolerability of the 2009 A/H1N1 MF59-adjuvanted influenza vaccine, administered sequentially or simultaneously with the seasonal 2009–10 virosomal-adjuvanted influenza vaccine, to paediatric kidney transplant recipients.

Methods. Thirty-two children and adolescents with transplanted kidneys and 32 age- and gender-matched healthy controls were randomized 1:1 to receive the pandemic vaccine upon enrolment and the seasonal vaccine 1 month later (16 transplant recipients and 16 healthy controls), or to receive the two vaccines simultaneously upon enrolment (16 transplant recipients and 16 healthy controls).

Results. When the pandemic vaccine was administered sequentially to the seasonal vaccine, it was significantly less immunogenic in the patients than in the controls (P < 0.05); when it was administered together with the seasonal vaccine, the immune response of both patients (P < 0.05) and controls (P < 0.05) was significantly greater than when it was administered sequentially. Seroconversion rates and the geometric mean titres of all of the seasonal antigens were significantly lower in the patients, regardless of the type of vaccine administration (P < 0.05). Simultaneous administration was associated with a better immune response against A/H1N1 and A/H3N2 antigens in both patients and controls, and did not increase the mild local and systemic reactions. No impact on renal function was observed.

Conclusions. Paediatric kidney transplant recipients have a lower immune response to the pandemic influenza A/H1N1 MF59-adjuvanted and seasonal virosomal-adjuvanted influenza vaccines than healthy controls. The simultaneous administration of the two vaccines seems to increase immune response to both pandemic and seasonal A/H1N1 and A/H3N2 antigens, and has the same safety profile as that of the pandemic vaccine administered sequentially to the seasonal vaccine.

The impact of eNOS, MTR and MTHFR polymorphisms on renal graft survival in children and young adults

BACKGROUND

The main cause of reduced long-term graft survival is chronic allograft injury. Cardiovascular risk factors such as hyperhomocysteinaemia, accumulation of asymmetric dimethylarginine, increased oxidative stress and decreased production of nitric oxide seem to play an important role. Functional polymorphisms of the endothelial isoform of nitric oxide synthase (NOS) gene cause an alteration in nitric oxide production. Nitric oxide levels, and thus oxidative stress, are also influenced by hyperhomocysteinaemia.

METHODS

We carried out a genetic analysis of endothelial nitric oxide synthase (eNOS) 894G>T, methionine synthase (MTR) 2756A>G and methylenetetrahydrofolate reductase (MTHFR) 677C>T/1298A>C in 268 renal allograft recipient/donor (D/R) matches, with respect to long-term graft survival.

RESULTS

While MTHFR 677C>T/1298A>G and MTR 2756A>G polymorphism distribution in both recipients (R) and donors (D) showed no significant difference between matches with loss of graft function and those with long-term graft survival, the frequency of the eNOS 894TT genotype of donors was significantly increased (P = 0.040) in matches with better graft survival. The multivariate analysis identified the eNOS 894 genotype and clinically acute rejection episodes as independent risk factors for graft loss (P = 0.0406 and P = 0.0093, respectively).

CONCLUSIONS

The association between eNOS 894G>T polymorphism of donors and graft survival seems to suggest a role for this gene in chronic allograft injury; however, further studies are needed to confirm this hypothesis.

Subclinical impairment of coronary flow velocity reserve assessed by transthoracic echocardiography in young renal transplant recipients

BACKGROUND

In renal transplant recipients (RTR) an increased risk to develop cardiovascular injury is present. Transthoracic Doppler echocardiographic assessment of coronary flow velocity reserve (CFVR), a sensitive and minimally invasive technique, was recently employed to detect both macrovascular and microvascular coronary artery disease (CAD) in different clinical settings. The prevalence of coronary involvement in young adult RTR is still unknown. The aim of the study was to investigate the presence of early cardiovascular damage in asymptomatic young adult RTR.

METHODS

Transthoracic Doppler echocardiographic-derived CFVR and common carotid intima-media thickness (IMT) were assessed in 25 asymptomatic young adult RTR (mean age 25.7+/-7.0 years; range 17.3-43.9) without CAD and 25 healthy controls.

RESULTS

CFVR was lower in young adult RTR compared to controls (2.8+/-0.6 vs. 3.5+/-0.8; P<0.001), meanwhile left ventricular wall motion and common carotid IMT were comparable in both groups. We found a negative correlation between CFVR and age (r=-0.50; P=0.018) and months on dialysis (r=-0.54; P<0.01).

CONCLUSIONS

Young adult RTR showed a reduced CFVR reflecting an impaired coronary microcirculation, which is significantly related to the age and duration of dialysis; coronary microvascular damage is detectable in the absence of changes in common carotid IMT. Non-invasive evaluation of CFVR by transthoracic stress echocardiography could be a reliable method for identification of early coronary microvascular involvement in young adult RTR.

The effect of CYP3A5 polymorphisms on the pharmacokinetics of tacrolimus in adolescent kidney transplant recipients

BACKGROUND

CYP3A5 gene polymorphism has been shown to influence tacrolimus (TAC) blood concentration and dose requirement in adult kidney transplant patients. The aim was to analyze retrospectively the modification induced by CYP3A5 gene polymorphism on TAC's pharmacokinetic parameters obtained from 26 adolescents receiving TAC as their main immunosuppressive drug.

MATERIAL/METHODS

The adolescent kidney transplant patients were genotyped for CYP3A5*3 and grouped accordingly. TAC dose, blood levels, and dose-normalized TAC blood concentration and volume of distribution obtained at different post-transplant periods during the first post-transplant year were correlated with the corresponding genotype.

RESULTS

During the first three months post-transplant, heterozygotes (CYP3A5*1/*3) displayed a lower TAC blood concentration than homozygotes (CYP3A5*3/*3) (at 1 month: 7.8+/-2.1 vs. 13.4+/-6 ng/ml, p=0.007) despite a therapeutic monitoring strategy. Between 3-12 months post-transplant, TAC blood concentration was comparable between the two groups, but a two-fold increase in the daily drug dose was necessary for the heterozygotes (at 6 months: 0.23+/-0.1 vs. 0.13+/-0.06 mg/kg, p=0.04). The dose-normalized TAC concentration [(ng/ml)/(mg/kg)] was significantly lower in patients displaying the CYP3A5*1/*3 polymorphism (at 2 weeks: 33+/-2.16 vs. 71.1+/-37.8, p=0.01; 6 months: 35.4+/-12.9 vs. 85.2+/-58.9, p=0.01). At the same time, the volume of distribution of the drug in the latter group was distinctly increased for the entire post-transplant year (at 6 months: 1.79+/-0.42 vs. 0.73+/-0.5 l/kg, p=0.001).

CONCLUSIONS

The great influence of CYP3A5 on the pharmacokinetics and pharmacodynamics of TAC in young transplant recipients suggests the need for pre-transplant screening of this polymorphism to improve TAC therapy.

No clear evidence of ACEi efficacy on the progression of chronic kidney disease in children with hypodysplastic nephropathy--report from the ItalKid Project database

BACKGROUND

Chronic kidney diseases (CKD) tend to progress to end-stage renal failure (ESRF). As it has been demonstrated that angiotensin-converting enzyme inhibitors (ACEi) have a renoprotective effect in adults with proteinuric disease and may be effective in reducing hyperfiltration and proteinuria, they are also frequently used as anti-progression agents in paediatric patients with CKD despite the lack of data confirming their role in the nephropathies peculiar to children. The aim of this study was to investigate whether patients with hypodysplastic CKD (the most common cause of ESRF in children) treated with ACEi show a significantly slower decline in creatinine clearance (Ccr).

METHODS

The analysis was based on the information available in the database of the ItalKid Project, a nationwide, population-based registry of chronic renal insufficiency (CRI) in children in Italy. Of the 822 patients with CRI due to hypodysplasia, we selected those who had been continuously treated with ACEi; the control patients were identified from the same diagnostic group and matched for gender, age and baseline Ccr.

RESULTS

Progression was analysed as the slope of Ccr in a total of 164 patients: 41 cases and 123 matched controls. There were no significant between-group differences in blood pressure, duration of follow-up or pre-study slope of Ccr (-0.31+/-2.26 vs -0.33+/-3.58 ml/min/1.73 m2/year; P=NS). After an average of 4.9+/-2.3 years, the mean slope of Ccr was 40% lower in the ACEi-treated cases in comparison to controls (-1.08+/-2.08 vs -1.80+/-4.42 ml/min/1.73 m2/year), however, this difference was not statistically significant (P=0.31).

CONCLUSIONS

We conclude that ACEi treatment does not significantly modify the naturally progressive course of hypodysplastic nephropathy in children and further studies are necessary before such treatment is routinely proposed for anti-progression purposes in children with CKD.

Combined liver-kidney transplantation in glycogen storage disease Ia: a case beyond the guidelines

Glycogen storage disease type Ia (GSD Ia) is a rare metabolic disorder due to hepatic glucose-6-phosphatase deficiency. Although great progress has been made in managing affected patients, severe hypoglycemia, lactic acidosis, hyperlipidemia, hepatic cytolysis, and impaired kidney function are frequent. Liver transplantation is the only radical treatment, for which the main indications are hepatic adenomatosis, hepatocellular carcinoma, or severe hepatic dysfunction. We present the case of a patient with end-stage renal disease without focal hepatic lesions and with moderate hepatic metabolic control, and we explain how combined liver-kidney transplantation (LKT) made it possible to correct the metabolic defects responsible for the impaired glucose homeostasis, liberalize the diet, and give birth to a healthy child after an uneventful pregnancy. Patients with end-stage renal disease that resulted from GSD Ia should be considered for LKT even in the absence of hepatic lesions with the aim of improving their quality of life.