Survival among children with portal vein thrombosis and end-stage liver disease

Al-Holou S, Mathur AK, Ranney D, Kubus J, Englesbe MJ. Survival among children with portal vein thrombosis and end-stage liver disease.
Pediatr Transplantation 2010: 14: 132–137. © 2009 John Wiley & Sons A/S.
Abstract:  Occlusive PVT concurrent with chronic liver disease is a common clinical entity among pediatric patients referred for transplantation. The natural history of PVT is unknown. Our aim was to determine, using a retrospective cohort design, if children under 13 yr with chronic liver disease and concomitant PVT have an increased mortality risk prior to and after transplantation. A total of 203 patients were included in the study. Nearly 10% of the population had PVT (n = 19); 63.2% of PVT patients (5.9% of total cohort) underwent liver transplantation (n = 12). PVT patients tended to be younger than non-PVT patients at evaluation (1.94 ± 3.51 vs. 3.79 ± 4.11, p = 0.059). Clinical and demographic factors were similar between the two groups. Regarding survival, four PVT patients died, of which two had undergone transplantation. Kaplan–Meier analyses indicated that PVT and non-PVT patients had similar survival from the time of evaluation, on the waiting list, and after transplant. Although limited by sample size, our study suggests that a diagnosis of PVT does not increase the mortality risk for children waiting for a liver transplant. Further study is needed to discern variations in mortality risk that may occur in the pediatric chronic liver disease population with PVT.     

Waiting list mortality for pediatric deceased donor liver transplantation in a Japanese living‐donor–dominant program

Living donor liver transplantation (LDLT) has become a major life‐saving procedure for children with end‐stage liver disease in Japan, whereas deceased donor liver transplantation (DDLT) has achieved only limited success. The annual number of pediatric liver transplantations is approximately 100‐120, with a patient 20‐year survival rate of 81.0%. In 2005, the liver transplantation program at the National Center for Child Health and Development in Tokyo, Japan, was initiated, with an overall number of 560 pediatric patients with end‐stage liver disease to date. In July 2010, our center was qualified as a pediatric DDLT center; a total of 132 patients were listed for DDLT up until February 2019. The indications for DDLT included acute liver failure (n = 46, 34.8%), metabolic liver disease (n = 26, 19.7%), graft failure after LDLT (n = 17, 12.9%), biliary atresia (n = 16, 12.1%), and primary sclerosing cholangitis (n = 10, 7.6%). Overall, 25.8% of the patients on the waiting list received a DDLT and 52.3% were transplanted from a living donor. The 5‐year patient and graft survivals were 90.5% and 88.8%, respectively, with an overall waiting list mortality of 3.0%. LDLT provides a better survival compared with DDLT among the recipients on the DDLT waiting list. LDLT is nevertheless of great importance in Japan; however, it cannot save all pediatric recipients. As the mortality of children on the waiting list has not yet been reduced to zero, both LDLT and DDLT should be implemented in pediatric liver transplantation programs.     

Biliary atresia: clinical profiles, risk factors, and outcomes of 755 patients listed for liver transplantation

OBJECTIVES: To test the hypothesis that risk analysis from the time of listing for liver transplantation (LT) focuses attention on areas where outcomes can be improved. STUDY DESIGN: Competing outcomes and multivariate models were used to determine significant risk factors for pretransplantation and posttransplantation mortality and graft failure in patients with biliary atresia (BA) listed for LT and enrolled in the Studies of Pediatric Liver Transplantation (SPLIT) registry. RESULTS: Of 755 patients, most were infants (age < 1 year). Significant waiting list mortality risk factors included infancy and pediatric end-stage liver disease (PELD) score > or = 20, whose components were also continuous risk factors. Survival posttransplantation (n=567) was 88% at 3 years. Most deaths were from infection (37%). Posttransplantation mortality risk factors included infant recipients, height/weight < -2 standard deviations (SD), use of cyclosporine versus tacrolimus and retransplantation. Graft failure risks included height/weight < -2 SD, cadaveric partial donors, donor age < or = 5 months, use of cyclosporine versus tacrolimus, and rejection. CONCLUSIONS: Referral for LT should be anticipatory for infants with BA with failed portoenterostomies. Failing nutrition should prompt aggressive support. Post-LT risk factors are mainly nonsurgical, including nutrition, the relative risk of infection over rejection, and the choice of immunosuppression.     

Unrelated umbilical cord blood transplantation and unrelated bone marrow transplantation in children with hematological disease: A meta-analysis

Abstract:  UCB has been used as an alternative source of HSC. Both unrelated donor BM and UCB are available as potential options for transplantation. However, there have been limited comparisons of the outcomes of unrelated donor UCBT vs. UBMT in the unrelated setting. Our aim is to observe the therapeutic efficacy of UCBT and UBMT for treatment of pediatric hematological diseases. We electronically searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and critically appraised all relevant articles (1989.1–2008.5). Comparative studies were carried out on clinical therapeutic effect of UCBT and UBMT with research on stem cells engraftment, complications, earlier mortality, and survival rate. We performed a meta-analysis using review manager 5.0 software (RevMan, The Nordic Cochrane Center, The Cochrane Collaboration) and adopted funnel plot regression to assess the publication bias. We obtained 324 records. Seven trials totaling 1453 patients have been assessed. Pooled comparisons of studies of UCBT and UBMT in children found that the incidence of engraftment failure and earlier transplantation-related mortality were higher with UCBT because of its delay of hematological recovery [OR = 4.96, 95% CI (3.25, 7.59), p < 0.00001 and OR = 2.36, 95% CI (1.79, 3.11), p < 0.00001 respectively], but CMV infection didn't increase obviously. There was no difference in long disease-free survival rate [OR = 0.85, 95% CI (0.65, 1.01), p = 0.06] between UCBT and UBMT due to the decrease of GVHD in UCBT [OR = 0.45, 95% CI (0.34, 0.60), p < 0.0001]. Our meta-analysis confirmed that UCBT in children is also an effective way to treat children with hematological disease and has equivalent survival outcomes compared with UBMT.     

Does the pediatric end-stage liver disease score or hepatic artery resistance index predict outcome after liver transplantation for biliary atresia?

The pediatric end-stage liver disease score (PELD) was devised and validated as a tool for predicting mortality and morbidity in children with chronic liver disease waiting for a liver transplant (LT). It has become a useful guide for prioritizing organ allocation in the United States. The hepatic artery resistance index (HARI) also predicts waiting list mortality in children with biliary atresia. Does the PELD score or HARI predict outcome after LT for biliary atresia? Twenty consecutive children who underwent LT for biliary atresia between 2001 and 2005 were reviewed. Their PELD score was calculated periodically between listing and transplantation and HARI was measured at listing. Outcome variables were operative blood transfusion requirements, ICU stay and postoperative stay. Median age at LT was 8 (2–204) months. After allowing for the type of graft, the PELD score and the change in PELD score between listing and LT (ΔPELD) showed no significant correlation with blood transfusion requirements, but both the PELD score at listing and ΔPELD showed a trend toward a statistically significant positive correlation with overall hospital stay. Pre-transplant HARI showed a statistically significant positive correlation with the PELD score at listing (r = 0.46, p = 0.05) but did not correlate significantly with hospital stay. In this relatively small but homogeneous group of children undergoing LT for biliary atresia, PELD, and ΔPELD scores showed a trend toward a statistically significant positive correlation with overall hospital stay. However, neither PELD scores nor the pre-transplant HARI showed a definite correlation with outcome. Post-transplant complications are probably more important factors determining ICU and hospital stay in children currently transplanted for biliary atresia.     

Infectious complications in pediatric liver transplantation candidates

Cakir M, Arikan C, Akman SA, Baran M, Saz UE, Yagci RV, Zeytunlu M, Kilic M, Aydogdu S. Infectious complications in pediatric liver transplantation candidates.
Pediatr Transplantation 2010: 14: 82–86. © 2009 John Wiley & Sons A/S.
Abstract:  We analyzed infections that occurred within one month prior to LT, identified factors associated with their occurrence and effect of infections on post-transplant mortality. The study group included 40 consecutive children who underwent LT. Sites and types of infection and culture results were recorded prospectively. IID was assessed. Risk factors for the infectious events were analyzed. Forty infection episodes were found in 24 patients (60%); 90% were bacterial, 7.5% fungal, and 2.5% viral. Overall, IID was 38.2 per 1000 patient days. Sites of bacterial infection were urinary tract in 13 events (36.1%) and blood stream in 11 events (30.5%). Bacteremia (culture positive infection episodes) was identified in 19 events (52.7%). Gram-negative isolates were twice as frequent as Gram-positive infections (63.1% vs. 36.9%). Risk factors for the infectious complications were young age, low body weight, prior abdominal surgery, chronic liver disease related to biliary problems, presence of ascites, portal hypertension and cirrhosis, and high PELD score (p < 0.05 for all). Infectious complications in pediatric LT candidates are common. Preventive measures are important not only to reduce the infectious complications but also to prevent the post-operative mortality.     

应用儿童终末期肝病模型评分预测Kasai术后联合激素治疗胆道闭锁的短期预后

目的 应用儿童终末期肝病模型(pediatric of end-stage liver disease,PELD)评分系统预测Kasai手术联合激素治疗胆道闭锁患儿的预后.方法 80例胆道闭锁患儿随机分为Ksai手术联合激素组及单纯Kasai手术组,应用PELD评分系统对每例患儿进行评分,比较两种方法治疗后生化指标、病死率及PELD分值的不同,探讨PELD评分与预后的关系.结果 PELD分值小于16的手术联合激素组患儿总胆红素、凝血酶原时间的国际标准化比值(INR)及PELD分值分别为(23.3±1.1)mg/L、2.31±0.24和10.6±2.3,明显低于单纯手术组的(28.9±2.1)mg/L、2.63±0.18和13.2±2.7.白蛋白则高于单纯手术组,差异有统计学意义(P＜0.05).16≤PELD＜28的患儿手术联合激素治疗后总胆红素、INR及PELD分值分别为(78.7±1.7)mg/L、3.03±0.24和17.1±1.8.明显低于单纯手术组的(92.6±2.1)mg/L、3.42±0.29和20.8±2.4,差异有统计学意义(P＜0.05).白蛋白的水平比单纯手术组高,差异有统计学意义(P＜0.05).PELD≥28的患儿仅总胆红素两组之间比较有统计学差异.PELD＜28的患儿,手术联合激素组患儿的病死率明显低于单纯手术组,差异有统计学意义.而PELD≥28的患儿的病死率两组之间比较差异无统计学意义.结论 激素通过降低总胆红素、INR及PELD分值,改善肝功能.PELD分值在28以下的患儿,激素辅助治疗可提高这部分胆道闭锁患儿的短期生存率.PELD分值大于28的患儿,即使应用激素治疗也不能提高短期生存率.     

Outcomes in pediatric hepatitis C transplant recipients: Analysis of the UNOS database

HCV may lead to the development of ESLD in late childhood and, consequently, contributes to the need for liver transplantation. The aim of this study was to examine post‐transplant outcomes in HCV‐positive pediatric patients with ESLD from any cause and to determine the impact of the PELD scoring system, introduced in February 2002, on post‐transplant patient and graft survival. A retrospective analysis of the UNOS database from 1994 to 2010 was performed to assess graft and patient survival in pediatric HCV‐seropositive liver transplant recipients. Graft survival and patient survival comparing subjects in the pre‐PELD era and post‐PELD era were analyzed using Kaplan–Meier statistics. Factors associated with survival were identified using Cox regression analysis. Of 120 pediatric HCV transplant recipients, 80 were transplanted in the pre‐PELD era and 40 were transplanted post‐PELD. Median serum total bilirubin, INR, and creatinine were 4.8 mg/dL, 1.6, and 0.7 mg/dL in the pre‐PELD era vs. 5.5 mg/dL, 1.7, and 0.6 mg/mL, respectively, in the post‐PELD era (p NS). One‐yr graft survival in the pre‐PELD vs. post‐PELD era was 65.0% and 89.7%, respectively (p < 0.01); corresponding three‐yr graft survival was 57.3% vs. 76.2% (p = 0.04). One‐yr patient survival in the pre‐PELD vs. post‐PELD era was 79.0% and 97.5%, respectively (p < 0.01); corresponding three‐yr survival was 79.0% vs. 89.4% (p = 0.17). Twenty‐eight patients (23.3%) were retransplanted: 24 (30%) in the pre‐PELD era (median time to retransplant 272 days) and four (10%) in the post‐PELD era (median time to retransplant 586 days). Early follow‐up demonstrates a trend toward improved pediatric HCV liver transplant graft and patient survival in the post‐PELD era. Superior outcomes may be attributed to pretransplant factors, improved surgical technique and better treatment options for HCV infection.     

From living related to in-situ split liver transplantation: how to reduce waiting-list mortality

The insufficient number of suitable cadaveric organs for pediatric recipients is the cause of high pretransplant mortality rates and long waiting times. With the introduction of split and living related liver transplantation, the waiting list mortality rate has dropped from greater than 15% to less than 5% and children are transplanted more rapidly. A 5-year patient and graft survival rate of greater than 80% has been obtained in those centers where split and living related liver transplantations are routinely performed. The data analyzed in this paper show that the only current solution to cadaveric organ shortage is a 'multimodal' approach, where whole liver cadaveric transplantation is associated with split and living related liver transplantation.     

Lymphocytotoxic crossmatch in pediatric living donor liver transplantation

Abstract:  To investigate the relationship between the pretransplant LCT results and the outcome after pediatric LDLT in a single center. The clinical data of 76 children undergoing 79 LDLTs including three retransplantations from May 2001 to January 2006 were retrospectively analyzed. All of the children had end-stage liver disease, and their median age was 1.4 yr (range, six months to 16.5 yr). Immunosuppressive therapy consisted of cyclosporine- or FK-based regimens with steroids. The children were classified into two groups (positive or negative) according to the pretransplant LCT results. The incidences of post-transplant surgical complications and of rejection episodes were compared. The relationship between the pretransplant LCT results and patient and graft survival rates was also analyzed. Seventy-nine pretransplant crossmatch tests were done; 13 (16.5%) were positive, and 66 (83.5%) were negative. No significant difference was found in the pretransplant clinical factors between two crossmatch groups. There was no significant difference between the groups in the incidence of vascular and biliary tract complications, in the rate of early or steroid-resistant cellular rejections, or in one- and three-yr patient (91.7%, 91.7%, respectively, in the positive group, 93.5%, 93.5%, respectively, in the negative group, p = 0.80) and graft (92.3%, 92.3%, respectively, in the positive group, 88.8%, 86.4%, respectively, in the negative group, p = 0.63) survival. The present study demonstrates that there is no reason to do pretransplant LCT to select the living donor for pediatric LDLT.     

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 after pediatric liver transplantation impact of living donor transplantation on cost

OBJECTIVE: To compare the direct health care cost of living donor liver transplantation (LDLT) with that of cadaver donor liver transplantation (CDLT) in children and identify predictors of cost. STUDY DESIGN: All 16 children who underwent LDLT from January 1997 through January 2002 at Cincinnati Children's Hospital Medical Center comprised the study population. They were matched for age, diagnosis, and nutritional status with 31 children who received CDLT during the same era. A historic cohort analysis was performed. RESULTS: There was no difference in the 1-year mortality rates between both groups. Costs associated with graft retrieval contributed 15.3% and 31% of the initial transplant cost for LDLT and CDLT, respectively. Mean cost of care in the first year was 60.3% higher for LDLT than CDLT (P=.01). Multivariate analysis identified biliary complications and insurance status as predictors of cost for initial transplantation (R(2)=0.57), whereas biliary complications and pediatric end stage liver disease scores were identified as predictors of cost of care in the first year after transplantation (R(2)=0.77). CONCLUSIONS: The comprehensive cost of LDLT in the first year after transplantation is higher than cadaveric transplantation. This must be balanced against the time spent and care needs of patients on the waiting list.     

Chronic kidney disease in children following lung and heart–lung transplantation

Abstract:  CKD is a major co-morbidity in pediatric lung transplant recipients. We report the prevalence of renal impairment post-lung transplant at a single center, using a modified, age-adjusted eGFR for the best approximation of true GFR, and investigated associations and possible predictors of decline in renal function post-transplant. Renal function was assessed by eGFR pre-transplant, three and 12 months post-transplant, and at last follow-up. Decline in renal function was analyzed as percentage fall in eGFR in two phases (0–3 and 3–12). Furthermore, we investigated impact of gender, age, pre-transplant diagnosis and renal function, transplant type, early post-transplant dialysis, and tacrolimus trough levels on decline in eGFR using multivariate analysis. Over a five-yr period, 30 transplants were performed. Mean eGFR pretransplant was 117 mL/min/1.73 m² (s.d. 35) with mean decline in eGFR during the first three months post-transplant of 33% (s.d. 31, p < 0.001). Thereafter, mean decline in eGFR was 8% (s.d. 18, p = 0.02). None of the factors assessed were significantly associated with decline in eGFR post-transplant. In conclusion, many children have decline in renal function following lung transplantation, particularly early post-transplant. Unlike in adults, we were unable to detect any predictors of renal impairment in pediatric lung transplant recipients.     

Hypogammaglobulinemia: Incidence, risk factors, and outcomes following pediatric lung transplantation

Abstract:  Infection is the leading cause of morbidity and mortality in the first year following lung transplantation. HG after adult lung transplantation has been associated with increased infections and hospitalization as well as decreased survival. The purpose of this study is to define the incidence, risk factors, and outcomes of HG in the first year following pediatric lung transplantation. A retrospective review of all lung transplant recipients at a single pediatric center over a four-yr period was performed. All serum Ig levels drawn within one yr of transplantation were recorded. An association between HG during the first year after transplantation and age, race, gender, diagnosis leading to transplantation and clinical outcomes including hospitalization, infections requiring hospitalization, viremia, fungal recovery from BAL lavage, and mortality was sought. HG was defined using age-based norms. Fifty-one charts were reviewed. Mean (±s.d.) post-transplantation levels for IgG, IgA, and IgM were 439.9 ± 201.3, 82.3 ± 50.2, and 75.2 ± 41.4 mg/dL, respectively. HG was present in 48.8%, 12.2%, and 17.1% of patients for IgG, IgA, and IgM, respectively. Patients with HG for IgG were older (14.3 ± 3.8 vs. 9.2 ± 5.4 yr; p < 0.01). IgA and IgM HG were associated with invasive aspergillosis (p < 0.01 and p = 0.05, respectively). IgG and IgM levels inversely correlated with bacterial infections and hospital days, respectively (p < 0.01, p < 0.05). HG is a frequent complication following pediatric lung transplantation. Low Ig levels are associated with increased infections and hospital stay.     

Recombinant growth hormone use pretransplant and risk for post-transplant lymphoproliferative disease--a report of the NAPRTCS

Abstract:  rhGH, widely used to optimize linear growth in children with ESRD, also modulates B-cell precursor development and may be associated with malignancy development. To determine if rhGH use in children was associated with higher risk of PTLD, we analyzed retrospectively collected data on children with CRI, on dialysis or with renal transplants in a large multi-center registry of children with ESRD. Of the 194 LPD patients currently listed in the registry, 41 were previously enrolled in the CRI registry and 18/41 (43.9%) used rhGH during their period with CRI. Among CRI patients who later received a transplant, rates of PTLD post-transplant were significantly higher among rhGH users (18/407 or 4.4%) compared to patients who never used rhGH during their CRI follow-up and received a transplant (23/1240 or 1.9%, p = 0.009). After adjusting for the confounders of recipient age (at CRI and at transplant) and transplant era, the use of rhGH pretransplant was associated with a borderline higher risk for PTLD (odds ratio 1.88, 95% CI = 1.00–3.55, p = 0.05). In contrast, use of rhGH during dialysis or post-transplant only was not associated with a higher risk for PTLD. Continued monitoring is recommended.     

Hepatocellular carcinoma in children and effect of living-donor liver transplantation on outcome

Hepatocellular carcinoma (HCC) is primarily observed in the older children and in most cases it develops in association with liver cirrhosis. Liver transplantation offers a good chance for long-term cure. To evaluate the outcome of children with HCC and the impact of living-donor orthotopic liver transplantation (OLT) on survival a retrospective review of radiographic, laboratory, pathologic, and therapeutic data in 13 children (six female and seven male) with chronic liver disease accompanied with HCC were studied. The patients were divided into two groups according to therapeutic modality: transplanted and non-transplanted patients. Kaplan-Meier survival curves in various therapeutic groups were plotted. The mean age of patients was 6.4 +/- 4.8 yr. Pediatric end-stage liver disease score was adapted to model for end-stage liver disease score for HCC and ranged between 1-44 and 18-44, respectively. The underlying liver diseases were tyrosinemia type 1 (n = 6), chronic hepatitis B infection (n = 6), glycogen storage disease type 1 (n = 1). Alfa-feto protein levels were elevated in all patients except one. Median number of tumor nodules was three (1-10), median maximal diameter of tumor nodules was 3.4 cm (0.5-8). Eleven patients were eligible for OLT whereas two patients were not eligible. Seven of the 11 patients considered for transplantation underwent living-donor OLT. Remaining four patients died while waiting on cadaveric transplant list. Overall 1 and 4-yr survival rates for all patients were 53.3 and 26.6%, respectively, and were found significantly higher in transplanted children than non-transplanted children (72%, 72% vs. 33% and 16.6%). No patient had tumor recurrence at median of 36-month follow-up after OLT. OLT is a life-saving procedure for children with chronic liver disease accompanying with HCC. Living-donor OLT avoids the risk of tumor progression and transplant ineligibility in these children.     

Outcome of pediatric liver transplant recipients in Turkey: single center experience

To summarize the evolution of the pediatric liver transplant program in a developing country. Between April 1997, and September 2003, 32 cadaveric (CD) and 35 living donor (LD) liver transplantations were performed on 61 children (median age 3.8 yr, range 0.5-16) at Ege University Organ Transplantation and Research Center. The patient's charts were reviewed retrospectively. The outcome of patient and graft survival was analyzed and the incidence of graft loss, complications and rejections was calculated. Indications for liver transplantation were metabolic liver disease (n = 17), biliary atresia (n = 14), viral hepatitis (n = 4), autoimmune hepatitis (n = 6), cryptogenic cirrhosis (n = 11), fulminant liver failure (n = 5) and others (n = 5). Seven of 61 children with chronic liver disease had hepatocellular carcinoma concomitantly. Median pediatric end-stage liver disease score was 23 (range 1-54). Seven children (11.4%) were UNOS status I, 44 (72%) were UNOS status II and 10 (16.6%) were UNOS status III. The median follow-up of the study population was 3.6 yr (range 0.5-6). Actuarial patient survival rates at 1, 2, 3 and 4 yr were 86, 86, 71.3 and 65% in the CD group vs. 80, 76, 67 and 67% in the LR group, respectively (p = NS). Patients listed as UNOS status 1 had lower survival rates than patients listed as UNOS status 2 and 3 (p < 0.05). The mortality rate was 26.2%. Graft survival rates were 81, 81, 75 and 64% at 1, 2, 3 and 4-yr respectively. Six patients (9%) underwent retransplantation. The main complications were infections (64.7%) and surgical complications (43.2%) (including biliary complication, vascular problems, postoperative bleeding, small for size and large for size). The incidence of acute cellular rejection was 39.3%, whereas chronic rejection was 7.4%. The result of liver transplantation in Turkish children was slightly inferior to those reported for North American and European children. However, an important characteristic of these patients that distinguishes them from Europe and North America is that most were UNOS status IIa and UNOS status I (44%). Despite technical and medical progress, infectious and biliary problems have continued to be an important cause of mortality in these patients.     

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.     

Pretransplant six‐minute walk test predicts peri‐ and post‐operative outcomes after pediatric lung transplantation

The purpose of the pretransplant assessment in lung transplantation is to determine a patient's need for transplant as well as their potential survival post‐procedure. In 2005, the UNOS introduced the LAS, a calculation based on multiple physiologic measures to determine need and likelihood for survival. Measures include NYHA class and the 6‐MWT. Some adult studies indicate a positive correlation with 6‐MWT and waiting list survival. In pediatric/adolescent patients, there are minimal data regarding the predictive value of physiologic markers in either wait list survival or post‐transplant outcome. A retrospective cohort study of 60 consecutive lung transplantations from 1990 to 2008 was performed at a pediatric tertiary care facility. Functional pretransplant assessments were abstracted from the medical record and compared with outcomes after transplantation. Results: a 6‐MWT of >1000 ft (305 m) prior to transplantation correlated with a shorter ICU stay (7 vs. 11 days, p = 0.046) and fewer days of mechanical ventilation (2 vs. 4, p = 0.04). A pretransplant 6‐MWT greater than 750 ft (229 m) correlated with shorter overall hospitalization (37 vs. 20 days, p = 0.03). Measuring pretransplant 6‐MWT tests for pediatric patients is valuable in predicting peri‐operative outcomes after lung transplantation.     

Outcome of bowel perforation after pediatric liver transplantation

Abstract:  Bowel perforation is one of the causes of mortality after pediatric liver transplantation. The aim of this study was to evaluate the incidence, risk factors, clinical presentations, and outcomes of bowel perforation in pediatric liver recipients. This is a retrospective analysis of all pediatric patients who underwent liver transplantation at a single liver transplant center in Iran between 1999 and 2006. During this period 72 liver transplantations were performed in children <18 yr. Twenty-two children underwent 33 re-explorations after liver transplantation. Five bowel perforations occurred in four children (incidence, 6.9%). One patient required two re-explorations. The median time between liver transplantation and the diagnosis of the bowel perforation was seven days. All patients had abdominal distention before re-exploration. The sites of perforation were jejunum (n = 3) and ileum (n = 2), and simple repair was performed in all cases. Three children had a history of prior Kasai operation. One of them received high dose of methylprednisolone before bowel perforation. Two children expired after bowel perforation (mortality rate, 50%). Bowel perforation is relatively frequent after pediatric liver transplantation. Among risk factors, prior Kasai operation may have a role. We observed that abdominal distention is a sign of bowel perforation and a high index of suspicion is required for rapidly diagnosis of this complication. The outcome of bowel perforation is poor and its mortality is high. Further studies are needed to establish real risk factors for this complication.