Society of pediatric liver transplantation: Current registry status 2011-2018

BACKGROUND

SPLIT was founded in 1995 in order to collect comprehensive prospective data on pediatric liver transplantation, including waiting list data, transplant, and early and late outcomes. Since 2011, data collection of the current registry has been refined to focus on prospective data and outcomes only after transplant to serve as a foundation for the future development of targeted clinical studies.

OBJECTIVE

To report the outcomes of the SPLIT registry from 2011 to 2018.

METHODS

This is a multicenter, cross-sectional analysis characterizing patients transplanted and enrolled in the SPLIT registry between 2011 and 2018. All patients, <18 years of age, received a first liver-only, a combined liver-kidney, or a combined liver-pancreas transplant during this study period.

RESULTS

A total of 1911 recipients from 39 participating centers in North America were registered. Indications included biliary atresia (38.5%), metabolic disease (19.1%), tumors (11.7%), and fulminant liver failure (11.5%). Greater than 50% of recipients were transplanted as either Status 1A/1B or with a MELD/PELD exception score. Incompatible transplants were performed in 4.1%. Kaplan-Meier estimates of 1-year patient and graft survival were 97.3% and 96.6%. First 30 days of surgical complications included reoperation (31.7%), hepatic artery thrombosis (6.3%), and portal vein thrombosis (3.2%). In the first 90 days, biliary tract complications were reported in 13.6%. Acute cellular rejection during first year was 34.7%. At 1 and 2 years of follow-up, 39.2% and 50.6% had normal liver tests on monotherapy (tacrolimus or sirolimus). Further surgical, survival, allograft function, and complications are detailed.

Solid organ transplantation from hepatitis B virus-positive donors: consensus guidelines for recipient management

Use of organs from donors testing positive for hepatitis B virus (HBV) may safely expand the donor pool. The American Society of Transplantation convened a multidisciplinary expert panel that reviewed the existing literature and developed consensus recommendations for recipient management following the use of organs from HBV positive donors. Transmission risk is highest with liver donors and significantly lower with non-liver (kidney and thoracic) donors. Antiviral prophylaxis significantly reduces the rate of transmission to liver recipients from isolated HBV core antibody positive (anti-HBc+) donors. Organs from anti-HBc+ donors should be considered for all adult transplant candidates after an individualized assessment of the risks and benefits and appropriate patient consent. Indefinite antiviral prophylaxis is recommended in liver recipients with no immunity or vaccine immunity but not in liver recipients with natural immunity. Antiviral prophylaxis may be considered for up to 1 year in susceptible non-liver recipients but is not recommended in immune non-liver recipients. Although no longer the treatment of choice in patients with chronic HBV, lamivudine remains the most cost-effective choice for prophylaxis in this setting. Hepatitis B immunoglobulin is not recommended.

Heterogeneity and disparities in the use of exception scores in pediatric liver allocation

Physicians apply for Model for End-Stage Liver Disease/Pediatric End-Stage Liver Disease exception points on a case-by-case basis to improve an individual patient's chances of receiving a liver transplant. This retrospective cohort study describes trends in the use of exceptions among the pediatric liver waitlist population with chronic liver disease. The cohort (n = 3728) included all children with a diagnosis of chronic liver disease listed in the United Network for Organ Sharing transplant database for first isolated liver transplant between February 27, 2002 and March 31, 2013. Exception score requests were common (34%); 90% of requests were approved. The rate of exception score requests in 2013 was five times that of 2002 (incident rate ratios [IRR] 5.25, 95% confidence interval [CI] 3.19-8.63, p < 0.01). Patients of non-White race had exception score request rates 13% lower than patients of White race (IRR 0.87, 95% CI 0.77-0.98, p = 0.02). Older patients had lower rates of exception score requests than younger patients (p = 0.03). Request rates varied by region. Time spent at an active exception status nearly tripled the hazard rate for transplantation (hazard ratio = 2.90, 95% CI 2.62-3.21, p < 0.01). There is disparity in use of exceptions by race that is not explained by clinical disease severity, diagnosis, geography or other demographic factors.

Acute liver failure and transplantation in children

Acute liver failure (ALF) was relatively easy to recognise in the days before liver transplantation became available as rescue therapy, because the diagnosis was based on end-stage disease manifestations such as profound coagulopathy, jaundice, encephalopathy and cerebral oedema (in a patient with no history of chronic liver disease). These criteria no longer help us in an era in which we struggle to define which patients are going to progress to this end-stage picture in the time necessary for evaluation and listing for life-saving transplantation. Ideally, identifying which patients will recover spontaneously or with appropriate treatment would relieve the justifiable concern that some patients receive a transplant when, given time, they would have recovered. Currently, the data to guide us in avoiding death without transplantation and unnecessary transplantation remain elusive.

Reducing pediatric liver transplant complications: a potential roadmap for transplant quality improvement initiatives within North America

Though robust clinical data are available within transplantation, these data are not used for broad-based, multicentered quality improvement initiates. This article describes a targeted quality improvement initiative within the Studies of Pediatric Liver Transplantation (SPLIT) Registry. Using standard statistical techniques and clinical expertise to adjust for data and statistical reliability, we identified the pediatric liver transplant centers in North America with the lowest hepatic artery thrombosis rate and biliary complication rates. A survey was completed to establish current practices within the entire SPLIT group. Surgeons from the highest performing centers presented a detailed, technically oriented overview of their current practices. The presentations and discussion that followed were recorded and form the basis of the best practices described herein. We frame this work as a unique six-step approach roadmap that may serve as an efficient and cost effective model for novel broad-based quality improvement initiatives within transplantation.

Intestine transplantation in the United States, 1999-2008

Improving short-term results with intestine transplantation have allowed more patients to benefit with nearly 700 patients alive in the United States with a functioning allograft at the end of 2007. This success has led to an increase in demand. Time to transplant and waiting list mortality have significantly improved over the decade, but mortality remains high, especially for infants and adults with concomitant liver failure. The approximately 200 intestines recovered annually from deceased donors represent less than 3% of donors who have at least one organ recovered. Consent practice varies widely by OPTN region. Opportunities for improving intestine recovery and utilization include improving consent rates and standardizing donor selection criteria. One-year patient and intestine graft survival is 89% and 79% for intestine-only recipients and 72% and 69% for liver-intestine recipients, respectively. By 10 years, patient and intestine survival falls to 46% and 29% for intestine-only recipients, and 42% and 39% for liver-intestine, respectively. Immunosuppression practice employs peri-operative antibody induction therapy in 60% of cases; acute rejection is reported in 30%-40% of recipients at one year. Data on long-term nutritional outcomes and morbidities are limited, while the cause and therapy for late graft loss from chronic rejection are areas of ongoing investigation.

Pediatric transplantation in the United States, 1996-2005

Solid organ transplantation is accepted as a standard lifesaving therapy for end-stage organ failure in children. This article reviews trends in pediatric transplantation from 1996 to 2005 using OPTN data analyzed by the Scientific Registry of Transplant Recipients. Over this period, children have contributed significantly to the donor pool, and although the number of pediatric donors has fallen from 1062 to 900, this still accounts for 12% of all deceased donors. In 2005, 2% of 89,884 candidates listed for transplantation were less than 18 years old; in 2005, 1955 children, or 7% of 28,105 recipients, received a transplant. Improvement in waiting list mortality is documented for most organs, but pretransplant mortality, especially among the youngest children, remains a concern. Posttransplant survival for both patients and allografts similarly has shown improvement throughout the period; in most cases, survival is as good as or better than that seen in adults. Examination of immunosuppressive practices shows an increasing tendency across organs toward tacrolimus-based regimens. In addition, use of induction immunotherapy in the form of anti-lymphocyte antibody preparations, especially the interleukin-2 receptor antagonists, has increased steadily. Despite documented advances in care and outcomes for children undergoing transplantation, several considerations remain that require attention as we attempt to optimize transplant management.

Pediatric transplantation in the United States, 1995-2004

This article reviews trends in pediatric solid organ transplantation over the last decade, as reflected in OPTN/SRTR data. In 2004, children younger than 18 years made up nearly 3% of the 86,378 candidates for organ transplantation and nearly 7% of the 27,031 organ transplant recipients. Children accounted for nearly 14% of the 7152 deceased organ donors. The transplant community recognizes important differences between pediatric and adult organ transplant recipients, including different etiologies of organ failure, surgical procedures that are more complex or technically challenging, effects of development on the pharmacokinetic properties of common immunosuppressants, unique immunological aspects of transplant in the developing immune system and increased susceptibility to posttransplant complications, particularly infectious diseases. For these reasons, and because of the impact of end-stage organ failure on growth and development, the transplant community has generally provided pediatric candidates with special consideration in the allocation of deceased donor organs. Outcomes following kidney, liver and heart transplantation in children often rank among the best. This article emphasizes that the prospects for solid organ transplantation in children, especially those aged 1-10 years are excellent. It also identifies themes warranting further consideration, including organ availability, adolescent survival and challenges facing pediatric transplant clinical research.

Functional liver recovery parallels autologous gut salvage in short bowel syndrome

BACKGROUND/PURPOSE

Parenteral nutrition (PN) is life saving in short bowel syndrome. However, long-term parenteral nutrition is frequently complicated by a syndrome of progressive cholestatic liver disease that is considered to be irreversible beyond the early stages of cholestasis, particularly in the presence of any degree of fibrosis in the liver. The purpose of this study was to examine apparent improvement in PN-associated liver dysfunction in a cohort of children with short bowel syndrome.

METHODS

A retrospective case-record review of all patients managed within a dedicated Intestinal Rehabilitation Program (IRP) identified 13 patients with short bowel who had PN-associated liver dysfunction, defined for this purpose as hyperbilirubinemia or an abnormal liver biopsy.

RESULTS

At referral, 12 of the 13 patients were exclusively on PN, and one was on 50% PN. At current follow-up, 3 patients have achieved complete enteral autonomy from PN, and 7 patients have had smaller decrements in PN requirements. Specific operative procedures to improve intestinal function were undertaken in 11 patients; 4 patients also underwent cholecystectomies with biliary irrigation at the time of intestinal reconstruction. The median highest bilirubin level in these 13 patients was 10.7 mg% (range, 3.2 to 24.5 mg%). Liver biopsy results indicated that 5 patients were cirrhotic, 3 had bridging fibrosis, and 4 had severe cholestasis or lesser degrees of fibrosis. Of 10 survivors in this series, 9 patients currently have a serum bilirubin less than 1 mg% with a median bilirubin in the group of 0.6 mg% (range, 0.3 to 6.4 mg%). Twelve of the 13 patients in this series were initially referred for liver-small bowel transplantation.

CONCLUSIONS

This preliminary experience suggests that PN-dependent patients with advanced liver dysfunction in the setting of the short bowel syndrome may, in some instances, experience functional and biochemical liver recovery. The latter appears to parallel autologous gut salvage in most cases. As a corollary, the authors believe that even advanced degrees of liver dysfunction should not preclude attempts at autologous gut salvage in very carefully selected patients. Such a policy of "aggressive conservatism" may help avoid the need for liver/intestinal transplantation in some patients who appear to be not responding to PN.

Late graft loss and long-term outcome after isolated intestinal transplantation in children

BACKGROUND/PURPOSE

The aim of this study was to determine causes of late graft loss and long-term outcome after isolated intestinal transplantation in children at a single center.

METHODS

All children who underwent primary isolated intestinal transplantation at our center with a minimum follow-up of 1 year were the subject of this retrospective study.

RESULTS

Twenty-eight children underwent primary isolated intestinal transplantation. Median graft survival was 705 days (range, 0 to 2,630 days) and median patient survival was 1,006 days (range, 0 to 2,630 days). There were 6 deaths and 15 graft losses (including the 6 nonsurvivors). Seven of the losses occurred 6 or more months after transplant. Of these, 2 losses occurred because of death of the recipients of sepsis; both recipients had functioning grafts. The 5 remaining late graft losses occurred because of acute rejection in 2 patients, chronic rejection in 2 (1 with concomitant acute rejection) and a diffuse stricturing process without the histologic hallmarks of chronic rejection in the fifth. All late survivors with intact grafts are off total parenteral nutrition (TPN).

CONCLUSIONS

Late graft loss remains a concern in a small percentage of patients after isolated intestinal transplantation. Nutritional autonomy from TPN is possible in the majority of these children after transplantation.

Long-term results of intestinal transplantation for pseudo-obstruction in children

PURPOSE

The aim of this study was to determine long-term results of intestinal transplantation in children with pseudo-obstruction, particularly when stomach and colon are not part of the allograft.

METHODS

The authors conducted a case-record review of all children who underwent transplantation at our center for a primary diagnosis of pseudo-obstruction. Supplementary information was obtained from outpatient charts, computerized database, and telephone survey of parents.

RESULTS

Six small bowel and 3 liver-small bowel transplants were carried out in 8 patients between 1993 and 1999. Median follow-up is 40 months (range, 13 to 73 months). Median age at transplantation was 2.7 years (range, 0.7 to 12.8 years). Median graft survival in this series is 15 months (range, 1 day to 71 months). Stomach and colon were excluded from all allografts. Two children died 5 and 368 days after transplant and 2 graft losses occurred in 1 patient. Two children had lymphoproliferative disease; both are alive with functioning grafts. Five survivors with functioning grafts receive full enteral feedings at home. Four of the 5 have had ileostomies closed, and 3 have normal bowel movements.

CONCLUSIONS

Intestinal transplantation without stomach or colon provides children with chronic intestinal pseudo-obstruction with a good quality of life. The underlying disease poses special challenges in management.

PACE project: object-orientated modelling of paediatric practice

The need for useful clinical support based on integrated computerized systems is now well recognized. To build systems desired by busy clinicians requires accurate specifications. These specifications in turn require rigorous descriptions of the processes to be automated in a form which is understandable and unambiguous to both clinician and computer scientist. Despite these requirements communication between suppliers and users of computer systems often is poor. Detailed descriptions of health care with particular reference to child health were developed with an object-orientated technique. These descriptions take the form of conceptual models of the basic health care activities (evidence collection, assessing, planning and implementing management) and more specific departmental activities pertaining to paediatric intensive care, accident and emergency, and cystic fibrosis management. We have learned that once a modelling team becomes competent in applying the technique, object-orientated modelling can be a powerful tool for the description of complex processes such as those involved in present-day health care.

Basic health care functions: an object-orientated analysis

All clinical activities carried out by health care professionals can be seen as examples of what we have called the basic health care functions. These are collecting information concerning the patient, assessing the patient in the light of the information gathered, and then planning and administering the care which is deemed necessary. For a computerized clinical support system to be helpful to clinicians it is essential that the information and computer scientists responsible for building such systems have clear and detailed descriptions of the activities carried out by their clinical colleagues. One method of bridging this communication gap is object-orientated modelling. In this paper we present an object-orientated analysis of the basic health care functions, thus establishing a generic model on which descriptions of more specific clinical situations can be based.

Tracheal carcinoma following short term tracheostomy in childhood (a case report)

Carcinoma of the trachea is rare in comparison to other neoplasms of the respiratory tract. Cigarette smoking has been implicated in its aetiology, but unlike carcinoma of the bronchus and lung, the incidence of tracheal carcinoma has not risen with tobacco consumption (Hajdu et al., 1970; Ranke et al., 1962). It seems, then, that there is some mechanism or mechanisms which render the trachea especially resistant to malignant change.