Kidney transplantation in children with posterior urethral valves

Abstract:  There is controversy about the outcome of renal transplantation in patients with PUV. The objective of this study was to analyze the outcome of renal transplantation in children with PUV. Fifteen patients had a history of PUV as the etiology of their ESRD. Forty-five patients comprised a control group without lower urinary tract anomalies. Mean age and follow-up duration were not significantly different between the case and the control group (p = 0.1). The immunosuppressive protocol and the year of transplantation were similar in these two groups (p = 0.2, 0.4, respectively). Among patients with PUV, 37.5% had acute rejection; and 56.2% had chronic rejection. Among the controls, 22.2% had acute rejection and 28.8% had chronic rejection. None of these differences was significant. Mean survival time was seven yr in affected patients and 6.2 yr in the control group (p = 0.9). Among patients with PUV, the rate of graft survival in the first year after transplantation was 95%; and those in the third, fifth, and seventh yr, 91%, 65%, and 50%, respectively. For the controls, the graft survival was 83% at one yr; 80% at three yr; 71% at five yr; and 60% at seven yr after transplantation (p = 0.9). Conclusively, this study showed that a history of PUV had no effect on graft function. Graft survival was not different among these patients compared with patients free of these anomalies. We also showed that urological complications were few in these patients.     

Acute rejection episodes in pediatric renal transplant recipients with cytomegalovirus infection

Abstract:  CMV infection is the most important opportunistic virus infection after renal transplantation leading to increased patient mortality, graft loss, risk for acute rejection episodes and impaired renal function. The potential impact of prophylactic anti-viral therapy on long-term graft outcome is relevant. The aim of this study was to evaluate the incidence of CMV infection, its risk factors and long-term outcome in children after renal transplantation. 103 children (mean age 10.6 ± 5.3, range 1.6–22.0 yr) were monitored weekly for pp65 for the first 6–8 wk after renal transplantation, followed by a monthly monitoring for the first year. CMV infection occurred in 23/103 children (21.1%) with 10 patients (9.7%) developing CMV disease characterized by positive pp65 in the presence of organ involvement. The CMV R−/D+ and R+/D+ serostatus was significantly associated with an increased risk of CMV infection (p < 0.0001 and p = 0.009). 14/28 R−/D+ patients developed CMV infection despite prophylactic treatment with CMV hyperimmune globulin. The incidence of acute rejection episodes after or during CMV infection was significantly increased (p = 0.003) and the D+ serostatus was significantly associated with acute rejection episodes within the first year after transplantation (p = 0.006). In summary the overall incidence of CMV infection in this single center experience is 21.1%. The D+ serostatus represents a serious risk factor for both CMV infection and acute rejection episodes. In future the potential impact of different modalities of prophylactic anti-viral therapy on the prevention of acute rejection should be considered.     

Changes in left ventricular strain parameters following pediatric heart transplantation

STE is increasingly utilized to assess strain in a variety of pathologies. Strain measurements have demonstrated utility following HT x and may aid in the detection of rejection and CAV . Strain parameters have not been well defined in the pediatric HT x population. This study aimed to describe strain in pediatric HT x recipients compared to controls and assess changes over time. All pediatric HT x recipients with available echocardiograms (2004‐2015) without rejection or CAV were identified. Longitudinal and circumferential strain was measured at <1 month, 1 year, 3 years, and 5 years post‐transplant and compared to controls. A total of 218 echocardiograms were analyzed in 79 HT x recipients. At <1 month post‐transplant, there was a significant decrement in longitudinal strain (GLS ?14.6 vs ?19.2, P  < .001) with concurrent augmentation of circumferential strain (GCS ?27.3 vs ?24.3, P  = .005). By 1 year post‐HT x, all strain parameters normalized and were not significantly different from the control population. In the absence of graft complications, strain parameters did not change up to 5 years post‐transplant. Abnormal longitudinal strain parameters are present in the early post‐HT x period with a compensatory increase in circumferential strain. These changes normalize by 1 year post‐transplant and do not change over time in the absence of graft complications.     

Nutrition, anthropometry, gastrointestinal dysfunction, and circulating levels of tumour necrosis factor alpha receptor I and interleukin-1 receptor antagonist in children during stem cell transplantation

Abstract:  To evaluate anthropometry, nutrition and gastrointestinal dysfunction, and to characterize the relation between these parameters and the inflammatory activity evaluated by plasma levels of soluble tumour necrosis factor alpha receptor I (sTNFRI) and interleukin-1 receptor antagonist (IL-1Ra) levels during stem cell transplantation (SCT) in children. Clinical assessments and blood sampling were performed on days −3, 0, +7, +15 and +31 in eight children undergoing SCT. Energy intake, anthropometry, gastrointestinal dysfunction (WHO toxicity score) and sTNFRI and IL-1Ra were evaluated. The energy intake was below recommended levels. There was a loss of lean body mass (arm muscle area)(median, 2031 mm² (day -3) vs 1477 mm² (day 31); p = 0.04), and of fat mass (arm fat area) (791 mm² (day -3) vs 648 mm² (day +31); p = 0.04). sTNFRI was elevated throughout the course of transplantation, and peaked after the day of graft infusion (day 0). sTNFRI levels at day 0 predicted changes in weight SDS (r = 0.65; p = 0.05), triceps skinfold SDS (r = 0.85; p = 0.007) and gastrointestinal dysfunction (r = 0.88; p = 0.004). Likewise, IL-1Ra levels at day 0 correlated with the gastrointestinal dysfunction (r = 0.83; p = 0.01) and with the change in weight SDS (r = 0.77; p = 0.03). This study suggests that pretransplant levels of inflammatory markers are associated with posttransplant symptoms of gastrointestinal dysfunction and loss of both fat and lean body mass. Future studies should adress if the use of conditioning regimens with limited proinflammatory cytokine inducing activity, anti-inflammatory agents, or more optimised nutritional support can reduce the burden of such posttransplant complications.     

Detection of gastro‐oesophageal reflux in the neonatal unit

Aim

To determine whether a pH probe or multichannel intraluminal impedance (MII) more frequently detected gastro‐oesophageal reflux and test the hypothesis that acid reflux was associated with lower baseline impedance.

Methods

A prospective study of infants in whom reflux was suspected and evaluated using combined pH and multichannel impedance. Studies were considered abnormal if the acid index was >10% or there were >79MII reflux events in 24 hours. The acid index was the percentage of total study time with a pH

Results

Forty‐two infants [median gestational age 31 (range 23–42) weeks] were assessed. Only nine infants (21%) had abnormal studies, seven detected by pH monitoring, one by MII monitoring and one by both techniques (p = 0.04). After correcting for gestational age and post‐natal age, baseline impedance remained negatively correlated with the acid index (r = ?0.34, p = 0.038) and the maximum ACT (r = ?0.44, p = 0.006).

Conclusion

Clinical suspicion of reflux was frequently incorrect, and reflux was more frequently detected by a pH probe. The inverse relationship of acid reflux to baseline impedance suggests that mucosal disruption may result from acid reflux in this population.

     

Potential influence of tacrolimus and steroid avoidance on early graft function in pediatric renal transplantation

Abstract:  With the increasing adoption of steroid-sparing immunosuppression protocols in renal transplantation, it is important to evaluate any adverse effects of steroid avoidance on graft function. Early graft function, measured by CrCl was retrospectively studied in 158 consecutive pediatric renal transplant recipients from 1996 to 2005, receiving either steroid-free or steroid-based immunosuppression. Patients receiving steroid-free immunosuppression vs. steroid-based immunosuppression had no difference change in CrCl (ΔCrCl) in the first week post-transplantation (p = 0.12). When stratified by corticosteroid usage, patients with higher tacrolimus trough levels (≥14 ng/mL) had slower graft function recovery in the first week post-transplantation than those with lower tacrolimus trough levels (p = 0.008) in the steroid-free group only. Despite initial slower graft function recovery in this subgroup, there was no negative impact on graft function in the steroid-free group; in fact steroid-free patients trended towards better CrCl at six months (p = 0.047) and 12 months (p < 0.001) post-transplant than the steroid-based group. With the improved immunological outcomes with steroid avoidance, close surveillance should be performed of tacrolimus levels to avoid levels >14 ng/mL. In patients with slow recovery of early graft function, short-term perioperative steroids may be considered.     

Pharmacokinetic monitoring of intravenous cyclosporine A in pediatric stem-cell transplant recipients. The trough level is not enough

Abstract:  In order to monitor CsA serum levels after SCT, trough levels (C0) are widely used. The aim of this study was to estimate the population and individual PK parameters for patients receiving intravenous CsA after SCT. In 27 pediatric patients after SCT receiving CsA (3 mg/kg/day) every 12 h, a total of 289 CsA concentrations was obtained. To describe the PK parameters of CsA, a two-compartment model with first order elimination was used. Covariate analysis identified body weight, age, and the co-administration with itraconazole and tobramycine as factors influencing the Cl. The statistical comparison of AUC, trough level, and C2 indicates a correlation between AUC and C2, but no correlation between the AUC and C0, r = 0.24 (p = 0.146) vs. r = 0.526 (p = 0.000692), respectively. Our results underscore the fact that CsA trough levels do not reflect the drug exposure in patients receiving intravenous CsA after SCT. By contrast, CsA blood levels measured 2–6 h after CsA infusion showed a better correlation with the AUC. Our data provide new information to optimize the balancing act between GvHD-prophylaxis, graft vs. leukemia effect, and CsA side-effects after SCT.     

Non-adherence to post-transplant care: prevalence, risk factors and outcomes in adolescent liver transplant recipients

Abstract:  This study examined the prevalence, demographic variables and adverse outcomes associated with non-adherence to post-transplant care in adolescent liver transplant recipients. We conducted a retrospective chart review of 111 adolescent patients (age 12–21 yr) greater than six months post-transplantation and defined non-adherence as not taking the immunosuppressive(s) or not attending any clinic visit in 2005. Fifty subjects (45.0%) were non-adherent and 61 (55.0%) were adherent. Twenty percent of the subjects did not attend clinic and 10.9% did not complete laboratory tests. Non-adherence was significantly associated with fewer completed laboratory tests (p < 0.0001), single parent status (p < 0.0186), and older age and greater years post-transplantation by both univariate and multivariate analyses (p < 0.008, p < 0.0141 and p < 0.0012, p < 0.0174, respectively). Non-adherence to medication was significantly associated with a rejection episode in 31 patients (p < 0.0069) but not in the subgroup of seven patients who stopped their immunosuppression completely. Non-adherence to post-transplant care is a prevalent problem in adolescents particularly of an older age and greater years post-transplantation. Rejection was a significant consequence of medication non-adherence except in a subgroup with presumed graft tolerance who discontinued their immunosuppression. These results emphasize the need for strict monitoring of adherence to post-transplant care to improve long-term survival and quality of life in adolescent transplant patients.     

Correlation of nitrites in breath condensates and lung function in asthmatic children

We aimed to evaluate the value of exhaled breath condensates in monitoring airway inflammation in childhood asthma before and after high altitude climate therapy.
Forty-eight asthmatic children on regular anti-asthma treatment with a normal FEV₁ and positive skin prick test for house dust mites were recruited. All children had been referred to an alpine clinic for high altitude climate therapy, because of persistent asthmatic symptoms despite use of daily anti-inflammatory treatment. Subjects were assessed on their arrival and before departure from the alpine clinic. Spirometry, bronchial provocation tests and measurements of nitrites in breath condensates were performed.
Median levels of nitrites were significantly higher before than after high altitude climate therapy (1.27 vs. 0.93 μ m ; p = 0.008). In addition, MEF₅₀ improved significantly (p < 0.0005). There was a significant correlation between nitrites in breath condensates and MEF₅₀ (r = −0.63, p < 0.0001), symptoms (r = 0.47, p = 0.0007) and airway hyper-reactivity (AHR) (r = −0.41, p = 0.004).
In summary, we found a reduction in nitrites in breath condensates after a high altitude climate therapy. Significant correlations were found between nitrites and MEF₅₀, AHR and symptoms. We conclude that the measurement of nitrites may be feasible to objectively assess airway inflammation in asthmatic children in order to detect ongoing inflammation in children with normal FEV₁ but persistent symptoms.     

Outcome of living donor renal allograft survival in children with focal segmental glomerulosclerosis

Abstract:  FSGS is the most frequent GN that may recur in a renal allograft. Compared with adults, the impact of FSGS on graft survival appears to be more significant in children. Thus we decided to assess graft survival and complications after renal transplantation in children with FSGS. Outcome of renal transplantation in 25 children with FSGS who received a renal transplant at Labafi Nejad Hospital was studied and compared with 75 patients as a control group. The mean follow-up duration was 68.16 (s.d. = 41.93) months. Other than demographics, variables such as DGF, acute rejection, number of acute rejection episodes, and graft failure in both groups were evaluated. Acute rejection was seen in 22/25 (88%) of FSGS group, compared to 40/75 (53.3%) in the control group. This difference was statistically significant (p = 0.001). DGF was seen in 4/25 (16%) and 13/75 (17.3%) in the FSGS and control groups, respectively (p = N.S.). The mean graft survival time was 115.61 (s.e.m. = 12.56) and 155.56 (s.e.m. = 7.16) month in FSGS and control group, respectively (p = N.S.). We demonstrated that graft function and survival were not significantly different in the FSGS and control patients. However, acute rejection episodes were more common in FSGS patients but without a significant impact on graft survival.     

Standardizing resistive indices in healthy pediatric transplant recipients of adult-sized kidneys

Gholami S, Sarwal MM, Naesens M, Ringertz HG, Barth RA, Balise RR, Salvatierra O. Standardizing resistive indices in healthy pediatric transplant recipients of adult-sized kidneys.
Pediatr Transplantation 2010: 14: 126–131. © 2009 John Wiley & Sons A/S.
Abstract:  Small pediatric recipients of an adult-sized kidney have insufficient renal blood flow early after transplantation, with secondary chronic hypoperfusion and irreversible histological damage of the tubulo-interstitial compartment. It is unknown whether this is reflected by renal resistive indices. We measured renal graft resistive indices and volumes of 47 healthy pediatric kidney transplant recipients of an adult-sized kidney in a prospective study for six months post-transplant. A total of 205 measurements were performed. The smallest recipients (BSA ≤0.75 m²) had higher resistive indices compared to recipients with a BSA between 0.75 and 1.5 m² (p < 0.0001) and to recipients with a BSA ≥ 1.5 m² (p < 0.0001). Resistive indices increased during the first six months in the smallest recipients (p = 0.02), but not in the two larger recipient groups (BSA 0.75–1.5 m² and ≥1.5 m²). All three BSA groups showed a reduction in renal volume after transplantation, with the greatest reduction occurring in the smallest recipients. In conclusion, renal transplant resistive indices reflect pediatric recipient BSA dependency. The higher resistance to intra-renal vascular flow and significant decrease in renal volume in the smallest group likely reflect accommodation of the size discrepant transplanted adult-sized kidney to the smaller pediatric recipient vasculature with associated lower renal artery flow.     

Urinary tract infections in pediatric renal transplant recipients – a two center risk factors study

Abstract:  UTI are common in renal Tx recipients and may significantly impact on the graft function. The aim of our study was to evaluate the prevalence, risk factors, and significance of UTI in Tx children. We performed a retrospective cross-sectional study of 76 Tx patients, median age at Tx was 13.4 yr. Twenty-one of 76 (28%) patients developed at least one UTI during the mean follow-up time of 3.3 ± 2.0 yr post-Tx. The first UTI occurred at a median of 160 days post-Tx. The RR of having UTI was significantly higher in patients with the primary diagnosis of obstructive uropathy (RR = 2.6, 95th CI = 1.1–6.0, p = 0.032), history of PN pre Tx (RR = 2.7, 95th CI = 1.3–5.4, p = 0.009) and pre Tx VUR (RR = 2.2, 95th CI = 1.1–4.5, p = 0.045). These three factors also significantly decreased the infection-free survival time to the first UTI. Most UTI caused reversible acute allograft dysfunction, but the long-term graft function could not be reliably assessed with SCr. In conclusion, UTI occurred in 28% of pediatric Tx recipients, mostly during the first year post-Tx despite antibiotic prophylaxis. The diagnosis of obstructive uropathy, history of UTI and VUR prior to Tx were significant risk factors.     

The impact of ischemic time on early rejection after pediatric heart transplant

Prolonged graft ischemia may be a risk factor for early rejection post‐HTx, but this has not been well studied in children. Furthermore, factors moderating the association between IT and early rejection have not been investigated. From 2004 to 2012, pediatric HTx recipients (n = 2381) were identified from the UNOS database. A ROC curve determined the optimal IT discriminating patients by the presence of early rejection. Separate univariate analyses identified factors associated with: (i) early (prior to hospital discharge) rejection, and (ii) IT. A multivariable logistic regression assessed independent risk factors for early rejection. We included interaction terms to evaluate whether IT's independent risk effect on early rejection is moderated via interaction with associated factors found in univariate analysis. Longer IT was associated with an increased risk of early rejection. In multivariable analysis, IT > 3.1 hours was an independent risk factor for early rejection (AOR 1.44, P = .01). No interaction terms between IT and any associated factors were significant. Longer IT is an independent risk for early rejection in pediatric HTx recipients. Better understanding the association between IT and early rejection may identify interventions to mitigate this risk.     

Renal function evaluated by measured GFR during follow-up in pediatric liver transplant recipients

Abstract:  Calcineurin inhibitors form the mainstay of immunosuppression in pediatric liver transplantation, but may cause significant nephrotoxicity. We evaluated renal function in liver transplant recipients treated with a tacrolimus-based immunosuppressive regimen. GFR was measured using 99 mTc-DTPA in patients pretransplant and annually thereafter. GFR calculated by Schwartz formula was compared with the measured values. Sixty patients who underwent 69 transplants were followed for at least one yr post-transplant (median three yr). In children over two yr of age at transplant GFR fell significantly from pretransplant (140 mL/min/1.73 m²) to one yr post-transplant (112 mL/min/1.73 m²) (p = 0.01) but thereafter there was no significant decline. In younger children the picture was confounded by maturation of renal function, but again there was no significant fall to five yr post-transplant. Although 13 (22%) patients developed renal dysfunction post-transplant, none required renal replacement therapy. cGFR correlated poorly with measured values (r = 0.21). Use of a tacrolimus-based immunosuppressive regimen is associated with an initial decline in GFR, though this picture is confounded in younger children by normal maturation of renal function. There is no further significant fall in GFR in the medium-term. The Schwartz formula is inaccurate in determining GFR in this patient group.     

Outcome of kidney transplantation in Canadian Aboriginal children in the province of British Columbia

Abstract:  Renal transplantation remains the therapy of choice for children and adolescents with ESRD. Differences in graft survival are observed in kidney transplant recipients of different race and ethnicities. Data in pediatric populations are limited and confounded by disparities in access to health care. We performed a retrospective single Canadian centre database review to determine the short- and long-term outcomes of kidney transplantation in Aboriginal children compared to non-Aboriginals. A total of 159 primary renal transplant recipients at BCCH between 1985 and 2005 were examined (15% Aboriginal). Aboriginal children had different etiologies of ESRD, and a higher percentage of females, but were similar in age at transplantation, cold ischemia time and living donation rate. Early graft outcomes such as delayed graft function, episodes of acute rejection in the first year post-transplant and estimated glomerular function rate at one yr were similar in both groups. Long-term graft survival, however, was significantly worse in the Aboriginal group, with a significantly increased rate of late rejections: 50% compared with 26.7% among non-Aboriginals (p = 0.03). In a province with uniform access to health care, significant differences in long-term graft outcome exist among Aboriginal children compared with non-Aboriginals.     

The effect of donor/recipient body surface area ratio on outcomes in pediatric kidney transplantation

Abstract:  In pediatric kidney transplantation, the effect of inadequate nephron dosing on graft survival remains undetermined. The aim of this study was to assess the use of D/R BSA, as a reliable indicator of adequate nephron dosing, and eventually a tool to optimize pediatric graft allocation. Following Institutional Review Board approval, we reviewed deceased donor pediatric kidney transplantation (N = 156). We divided patients into three groups, based on D/R BSA: A ≤0.8; B 0.81–1.19; C ≥1.2. Five-yr graft survival rates in the groups were: A 82.0%; B 94.9%; C 97.1% (p   =   0.01). Group C had the lowest rate of acute rejection, suggesting a protective effect of increased D/R BSA (group A = 35.7%, group B = 38.9%, group C = 18.8%; p   =   0.029). The logistic regression analysis showed that decreased D/R BSA ratio is a risk factor for loss of graft function, at one and five yr [i.e., group A OR 6 (95% CI 1.14–39.30, p   =   0.015) and OR 4.49 (95% CI 1.46–13.79, p = 0.009), respectively]. We conclude that for pediatric recipients, D/R BSA is a valuable adjunct when determining long-term graft survival. Its utility may avoid an alloimmune-independent risk factor, increasing the long-term protective value of a good matching policy.     

Basal insulin and total daily insulin dose in children with type 1 diabetes using insulin pumps

Objective:  To assess the contribution of basal insulin to the total daily dose (CBITDD) and to identify the determinant factors in children with type 1 diabetes mellitus.
Study design:  Cross-sectional study in which the basal insulin requirement was established based on a memory read-out of insulin delivery from pumps. Factors such as glycated haemoglobin A1c (HbA1c), fasting C-peptide, standard deviation score of body mass index (sdsBMI) and demographic data were determined during routine hospital visits. Study group included a total of 90 well-controlled diabetic children with the mean HbA1c 6.6 ± 0.7 (5.2–7.9), age 10.4 ± 4.4 yr (1.1–17.9 yr), diabetes duration 3.0 ± 2.6 yr (0.3–10.9 yr) and sdsBMI 0.08 (−2.27 to 1.79), excluding patients with ketoacidosis or infectious diseases.
Results:  Correlations between CBITDD and age (r = 0.39 and p < 0.005) and diabetes duration (r = 0.61 and p < 0.0001) and an inverse correlation with C-peptide (r = −0.41 and p = 0.0001) were found. C-peptide-positive patients had a significantly lower percentage of basal insulin compared with C-peptide-negative patients (20.6 ± 11 vs. 31.6 ± 11.0%, respectively; p = 0.0004); yet, no significant difference in total insulin daily dose (0.65 ± 0.3 vs. 0.78 ± 0.2 U/kg/d, respectively) was observed.
Conclusions:  The percentage of basal insulin in diabetic children is below 50% and in well-controlled diabetic children is related to the fasting C-peptide level, age of patient and diabetes duration but not to HbA1c and sdsBMI.     

The prognostic value of urinary chemokines at 6 months after pediatric kidney transplantation

Pediatric kidney transplantation is lifesaving, but long‐term allograft survival is still limited by injury processes mediated by alloimmune inflammation that may otherwise be clinically silent. Chemokines associated with alloimmune inflammation may offer prognostic value early post‐transplant by identifying patients at increased risk of poor graft outcomes. We conducted a single‐center prospective cohort study of consecutive pediatric kidney transplant recipients (<19 years). Urinary CCL 2 and CXCL 10 measured at 6 months post‐transplant were evaluated for association with long‐term eGFR decline, allograft survival, and concomitant acute cellular rejection histology. Thirty‐eight patients with a mean age of 12.4 ± 4.6 years were evaluated. Urinary CCL 2 was associated with eGFR decline until 6 months (ρ ?0.43; P  < .01), but not at later time points. Urinary CXCL 10 was associated with eGFR decline at 36 months (ρ ?0.49; P  < .01), risk of 50% eGFR decline (HR  = 1.04; P  = .02), risk of allograft loss (HR  = 1.05; P  = .01), borderline rejection or rejection episodes 6‐12 months post‐transplant (r .41; P  = .02), and Banff i  + t score (r .47, P  < .01). CCL 2 and CXCL 10 were also correlated with one another (ρ 0.54; P  < .01). CCL 2 and CXCL 10 provide differing, but complementary, information that may be useful for early non‐invasive prognostic testing in pediatric kidney transplant recipients.     

Association of mast cells and liver allograft rejection

Abstract:  MCs are important effector cells in a broad range of immune responses. Their role in liver allograft rejection is not clear. Twenty-one liver transplant recipients (mean age ± s.d.; 10.2 ± 4.1 yr) who experienced a rejection episode are included in this study. Biopsy specimens from normal livers (allograft biopsy with normal histopathology n = 5 and naïve livers n = 6), transplanted livers with CR (n = 5), and transplanted livers with ACR (n = 26) were studied. The total number of PT in each biopsy specimen was documented, and the number of PT that contained MCs was expressed as a percentage of the total number of PT. MCs, percentage of PT containing MCs and the average number of MCs/PT was significantly higher in rejection specimens than in control biopsy samples. All parameters were significantly higher in CR group than AR groups. Increasing grades of rejection was also associated with progressively more MCs and MC/PT ( r  = 0.68 p = 0.000; r  = 0.58 p = 0.002). Only serum bilirubin level was related to the MCs in AR group. Only MC/PT was detected as an independent predictor of graft survival (p = 0.011, RR 2.87 95% CI 1.3–6.5). Despite the fact that the role of MCs in liver allograft rejection is still unknown; they exist in inflammatory infiltrates during pediatric liver allograft rejection. MC-rich portal infiltrates may distinguish chronic liver rejection from other inflammatory states such as AR, hepatitis and biliary obstruction.     

The use of Doppler tissue imaging to predict cellular and antibody-mediated rejection in pediatric heart transplant recipients

Abstract:  DTI indices have been associated with cellular rejection in adult heart transplant recipients, but their predictive value in pediatric recipients is unknown. The purpose of this study was to evaluate DTI measures in the detection of cellular and AMR in pediatric heart transplant recipients. One hundred and forty-eight pediatric heart transplant recipients who had 267 cardiac catheterization procedures with EMB, echocardiogram with DTI, and BNP level performed on the same day were included in the study. For the mitral and tricuspid valves, the ratios (E/E') between the early diastolic inflow velocity by pulsed Doppler (E, m/s) and the early diastolic annular velocity by DTI (E', m/s) were obtained and compared between subjects with and without rejection. Of the 148 recipients, 30 subjects had a total of 37 episodes of rejection: 10 cellular (≥1B), 17 AMR, and 10 biopsy-negative clinical rejection. Mitral and tricuspid valve E/E' ratios were significantly higher in rejectors than in non-rejectors (5.5 ± 1.3 vs. 4.4 ± 1.4, p < 0.001 and 4.9 ± 2.1 vs. 4.1 ± 1.5, p < 0.01, respectively). By multivariate linear regression, mitral valve E/E' was an independent predictor of rejection. Mitral and tricuspid valve E/E' <5.0 had 93% and 89% NPV, respectively, for rejection. Mitral and tricuspid valve E/E' ratios <5.0 may be useful non-invasive screening measures to exclude rejection in pediatric heart transplant recipients.