Pediatric Candidates Research Articles

Improved waitlist and transplant outcomes for pediatric lung transplantation after implementation of the lung allocation score

Although the lung allocation score (LAS) has not been considered valid for lung allocation to children, several additional policy changes for pediatric lung allocation have been adopted since its implementation. We compared changes in waitlist and transplant outcomes for pediatric and adult lung transplant candidates since LAS implementation. The United Network for Organ Sharing database was reviewed for all lung transplant listings during the period 1995 to June 2014. Outcomes were analyzed based on date of listing (pre-LAS vs post-LAS) and candidate age at listing (adults >18 years, adolescents 12 to 17 years, children 0 to 11 years). Of the 39,962 total listings, 2,096 (5%) were for pediatric candidates. Median waiting time decreased after LAS implementation for all age groups (adults: 379 vs 83 days; adolescents: 414 vs 104 days; children: 211 vs 109 days; p < 0.001). The proportion of candidates reaching transplant increased after LAS (adults: 52.6% vs 71.6%, p < 0.001; adolescents: 40.3% vs 61.6%, p < 0.001; children: 42.4% vs 50.9%, p = 0.014), whereas deaths on the waitlist decreased (adults: 28.0% vs 14.4%, p < 0.001; adolescents: 33.1% vs 20.9%, p < 0.001; children: 32.2% vs 25.0%; p = 0.025), despite more critically ill candidates in all groups. Median recipient survival increased after LAS for adults and children (adults: 5.1 vs 5.5 years, p < 0.001; children: 6.5 vs 7.6 years, p = 0.047), but not for adolescents (3.6 vs 4.3 years, p = 0.295). Improvements in waiting time, mortality and post-transplant survival have occurred in children after LAS implementation. Continued refinement of urgency-based allocation to children and broader sharing of pediatric donor lungs may help to maximize these benefits.

Surgery for epileptogenic cerebral dysplasia in children.

New developments in diagnostic methods, technical improvements in the surgical field, and a better understanding of the effects of epilepsy on the developing brain are contributing to the general observation that more children with epilepsy are being treated surgically. Malformations of cortical development are the most common cause of seizures in pediatric surgical candidates, and the best predictor of seizure freedom after surgery appears to be the complete removal of the epileptogenic lesion. To achieve this goal in challenging cases, such as magnetic resonance imaging-negative or multifocal lesions, a staged approach with pre- and/or post-resective invasive electroencephalography monitoring has increasingly been used at a number of centers. As the experience with this approach has grown, and the risks and benefits are better understood, a larger number of patients with epilepsy have been identified as potential surgical candidates. In this review, a number of the recent developments in pediatric epilepsy surgery are discussed.

Targeting tubers in paediatric epilepsy surgery candidates.

This scientific commentary refers to ‘Centre of epileptogenic tubers generate and propagate seizures in tuberous sclerosis’, by Kannan et al. (doi:10.1093/brain/aww192) . First described clinically at the end of the 19th century, tuberous sclerosis complex is a multi-organ system disorder displaying characteristic skin involvement, benign tumours, and hamartomatous and cystic lesions. Affected children often experience debilitating focal epilepsy that typically begins in very early life and remains medically resistant. For this reason, surgical therapy was advocated as far back as 1966 (Perot et al. , 1966) based on the hypothesis that a single tuber might well be responsible for the epileptogenesis. This conceptual approach has been well validated, and yet the precise anatomical and physiological substrates of focal epilepsy in affected individuals remain a matter of debate. Do the seizures in tuberous sclerosis complex begin directly within the cortical tuber itself or does onset occur in surrounding tissue? And do seizures propagate from the seizure onset zone to distant non-tuberal sites? In this issue of Brain , Kannan and co-workers provide elegant support for a central role of the tuberal core in seizure initiation and propagation (Kannan et al. , 2016). Building on previous analyses (Mohamed et al. , 2012), Kannan et al. investigated the spatio-temporal patterns of seizure onset and propagation in children with tuberous sclerosis complex by analysing intracranial EEG recordings in 10 patients with focal epilepsy. Multiple depth and surface electrodes sampled tubers and perituberal cortex both during seizures and interictally. In many cases, depth electrodes were positioned directly into the centre of the tuber. Analyses of 10 electro-clinically distinct seizure types revealed that nine originated in the centre of the tuber; one began in the tuberal rim, and most importantly, none originated in perituberal tissue alone. In all cases, electrical seizure activity preceded …

Heart.

As the number of candidates listed for heart transplant continues to rise, it is encouraging that the number of heart transplants also continues to rise steadily each year. Evaluation of waitlist activity demonstrates a growing number of adult candidates removed from the list due to undergoing transplant, but also growing numbers of adult candidates added to the list over the past 3 years. In 2014, 2679 heart transplants were performed, an increase of 28.4% since 2003, and the number of people living with a transplanted heart continued to increase. The number of new pediatric candidates added to the heart transplant waiting list increased to 593 in 2014. The number of pediatric heart transplants performed each year increased from 293 in 2003 to 410 in 2014. Almost 60% of pediatric candidates waiting on December 31, 2014, had been waiting for less than 1 year, compared with 43.0% in 2004. Among pediatric patients who underwent transplant in 2008-2012, overall cumulative incidence of death at 1, 3, and 5 years was 9.2%, 14.7%, and 18.3%, respectively.

Long-term results of arteriovenous fistula for hemodialysis in pediatric candidates

Long-term results of arteriovenous fistula for hemodialysis in pediatric candidates

Improving Access for Pediatric and Adult Cochlear Implant Candidates in Ontario

In 2011, the Ontario Ministry of Health and Long-Term Care announced the one-time allocation of $5.9 million to be shared by cochlear implant programs at five Ontario hospitals. The primary goal of this reform was to address cochlear implant wait times. More specifically, this funding was aimed at reducing adult wait times by 50% and to completely eliminate pediatric waiting lists. Prior to this funding, wait times for pediatric and adult cochlear implants were known to exceed four years. The funding was provided in response to a growing body of research that demonstrates increased speech perception and vocabulary among pediatric recipients, and pressure from parents of children on cochlear implant waiting lists, surgeons and other involved healthcare providers (e.g., auditory verbal therapists, audiologists, and speech language pathologists). The decision to increase funding was also influenced by government stakeholders who believed this one-time investment would be returned as pediatric patients reach adulthood and are better equipped to participate in mainstream (i.e., hearing) society. While this one-time funding model has the potential to eliminate wait times for pediatric patients, thereby ensuring these children can access therapeutic services as early as possible, it does not address the future of cochlear implant waiting lists or the capacity of health human resources to absorb this sudden and unprecedented influx of pediatric patients. Le Ministere de la Sante et des Soins de Longue Duree de l'Ontario a annonce en 2011 le deblocage d'un budget de $5.9 million a partager entre les programmes d'implants cochleaires dans cinq hopitaux de la province. La reforme visait avant tout a diminuer les temps d'attente pour les implants cochleaires. Plus particulierement, cet apport budgetaire avait pour but de diminuer les delais de 50% pour les adultes et de les eliminer completement pour les enfants. Les delais d'attente pour les adultes et les enfants confondus etaient consideres comme superieurs a quatre ans. Le coup de pouce budgetaire etait en reaction a des resultats de recherche demontrant une amelioration de la comprehension du discours et du vocabulaire chez les enfants recevant l'implant, et de la pression de la part des parents des enfants sur liste d'attente d'implants cochleaires, des chirurgiens et des autres producteurs de soins impliques (par exemple les therapeutes de la communication auditivo-verbale, les audiologistes, ou les orthophonistes). La decision de donner un coup de pouce budgetaire a aussi ete influencee par les conseillers du gouvernement qui pensaient que cet investissement ponctuel serait rentabilise quand les enfants traites atteindraient l'âge adulte mieux equipes pour la vie en societe. Si cet apport ponctuel peut eliminer les delais d'attente pour les enfants, leur assurant ainsi l'acces aux services therapeutiques aussi tot que possible, il ne resoud en rien le probleme des listes futures ni la capacite des ressources humaines sanitaires a absorber un tel afflux soudain de patients pediatriques .

Intestine.

Intestine and intestine-liver transplant plays an important role in the treatment of intestinal failure, despite decreased morbidity associated with parenteral nutrition. In 2014, 210 new patients were added to the intestine transplant waiting list. Among prevalent patients on the list at the end of 2014, 65% were waiting for an intestine transplant and 35% were waiting for an intestine-liver transplant. The pretransplant mortality rate decreased dramatically over time for all age groups. Pretransplant mortality was highest for adult candidates, at 22.1 per 100 waitlist years compared with less than 3 per 100 waitlist years for pediatric candidates, and notably higher for candidates for intestine-liver transplant than for candidates for intestine transplant without a liver. Numbers of intestine transplants without a liver increased from a low of 51 in 2013 to 67 in 2014. Intestine-liver transplants increased from a low of 44 in 2012 to 72 in 2014. Short-gut syndrome (congenital and other) was the main cause of disease leading to both intestine and intestine-liver transplant. Graft survival improved over the past decade. Patient survival was lowest for adult intestine-liver recipients and highest for pediatric intestine recipients.

An algorithmic approach to the management of unrecognized hydrocephalus in pediatric candidates for intrathecal baclofen pump implantation.

Background:Complications of intrathecal baclofen (ITB) pump implantation for treatment of pediatric patients with spasticity and dystonia associated with cerebral palsy remain unacceptably high. To address the concern that some patients may have underlying arrested hydrocephalus, which is difficult to detect clinically because of a low baseline level of neurological function, and may contribute to the high rates of postoperative cerebrospinal fluid leak, wound breakdown, and infection associated with ITB pump implantation, the authors implemented a standardized protocol including mandatory cranial imaging and assessment of intracranial pressure (ICP) by lumbar puncture prior to ITB pump implantation.Methods:A retrospective case series of patients considered for ITB pump implantation between September 2012 and October 2014 at Seattle Children's Hospital is presented. All patients underwent lumbar puncture under general anesthesia prior to ITB pump implantation and, if the opening pressure was greater than 21 cmH2O, ITB pump implantation was aborted and alternative management options were presented to the patient's family.Results:Eighteen patients were treated during the study time period. Eight patients (44.4%) who had ICPs in excess of 21 cmH2O on initial LP were identified. Eleven patients (61.1%) ultimately underwent ITB pump implantation (9/10 in the “normal ICP” group and 2/8 in the “elevated ICP” group following ventriculoperitoneal shunt placement), without any postoperative complications.Conclusions:Given the potentially high rate of elevated ICP and arrested hydrocephalus, the authors advocate pre-implantation assessment of ICP under controlled conditions and a thoughtful consideration of the neurosurgical management options for patients with elevated ICP.

Kidney.

Kidney transplant provides significant survival, cost, and quality-of-life benefits over dialysis in patients with end-stage kidney disease, but the number of kidney transplant candidates on the waiting list continues to grow annually. By the end of 2014, nearly 100,000 adult candidates and 1500 pediatric candidates were waiting for kidney transplant. Not surprisingly, waiting times also continued to increase, along with the number of adult candidates removed from the list due to death or deteriorating medical condition. Death censored graft survival has increased after both living and deceased donor transplants over the past decade in adult recipients. The majority of the trends seen over the past 5 years continued in 2014. However, the new allocation system was implemented in late 2014, providing an opportunity to assess changes in these trends in the coming years.

Optimizing the utilization of kidneys from small pediatric deceased donors under 15 kg by choosing pediatric recipients.

Currently, most kidneys from small pediatric deceased donors are transplanted into adult recipients (i.e., PTA). However, due to the weight mismatch, there is a high discard rate and a high ratio of EBKTs if adopting PTA. Here, we sought both to optimize utilization of these challenging but scarce donor grafts by selecting pediatric recipients and to characterize the feasibility and efficacy of this PTP allocation strategy. From February 2012 to October 2014, kidneys from 27 infant donors ≤ 15 kg were procured and distributed to 38 pediatric candidates in our center. The grafts were utilized for EBKT if the donor weighed 2.5-5 kg and for SKT if the donor weighed 5-15 kg, leading to 10 EBKTs and 28 SKTs. The overall utilization rate from small pediatric deceased donors was 94.12%. After a follow-up of 3-26 months, the graft survival rate was 89.47%, with four graft losses due to vascular thrombosis. Kidneys from low-body-weight donors should be applied to pediatric recipients, and the kidneys from infant donors ≥ 5 kg can be used in single-kidney-transplant procedures at experienced centers to optimize utilization.

Broader Geographic Sharing of Pediatric Donor Lungs Improves Pediatric Access to Transplant.

US pediatric transplant candidates have limited access to lung transplant due to the small number of donors within current geographic boundaries, leading to assertions that the current lung allocation system does not adequately serve pediatric patients. We hypothesized that broader geographic sharing of pediatric (adolescent, 12-17 years; child, <12 years) donor lungs would increase pediatric candidate access to transplant. We used the thoracic simulated allocation model to simulate broader geographic sharing. Simulation 1 used current allocation rules. Simulation 2 offered adolescent donor lungs across a wider geographic area to adolescents. Simulation 3 offered child donor lungs across a wider geographic area to adolescents. Simulation 4 combined simulations 2 and 3. Simulation 5 prioritized adolescent donor lungs to children across a wider geographic area. Simulation 4 resulted in 461 adolescent transplants per 100 patient-years on the waiting list (range 417-542), compared with 206 (range 180-228) under current rules. Simulation 5 resulted in 388 adolescent transplants per 100 patient-years on the waiting list (range 348-418) and likely increased transplant rates for children. Adult transplant rates, waitlist mortality, and 1-year posttransplant mortality were not adversely affected. Broader geographic sharing of pediatric donor lungs may increase pediatric candidate access to lung transplant.

Bioethics and medical/legal considerations on cochlear implants in children

Cochlear implants are the best treatment for congenital profound deafness. Pediatric candidates to implantation are seen as vulnerable citizens, and the decision of implanting cochlear devices is ultimately in the hands of their parents/guardians. The Brazilian Penal Code dictates that deaf people may enjoy diminished criminal capacity. Many are the bioethical controversies around cochlear implants, as representatives from the deaf community have seen in them a means of decimating their culture and intrinsic values. ObjectiveThis paper aims to discuss, in bioethical terms, the validity of implanting cochlear hearing aids in children by analyzing their vulnerability and the social/cultural implications of the procedure itself, aside from looking into the medical/legal aspects connected to their criminal capacity. Materials and MethodsThe topic was searched on databases Medline and Lilacs; ethical analysis was done based on principialist bioethics. ResultsCochlear implants are the best therapeutic option for people with profound deafness and are morally justified. The level of criminal capacity attributed to deaf people requires careful analysis of the subject's degree of understanding and determination when carrying out the acts for which he/she has been charged. ConclusionCochlear implants are morally valid. Implantations must be analyzed on an each case basis. ENT physicians bear the ethical responsibility for indicating cochlear implants and must properly inform the child's parents/guardians and get their written consent before performing the procedure.

Delineation of somatosensory finger areas using vibrotactile stimulation, an ECoG study.

In surgical planning for epileptic focus resection, functional mapping of eloquent cortex is attained through direct electrical stimulation of the brain. This procedure is uncomfortable, can trigger seizures or nausea, and relies on subjective evaluation. We hypothesize that a method combining vibrotactile stimulation and statistical clustering may provide improved somatosensory mapping. Seven pediatric candidates for surgical resection underwent a task in which their fingers were independently stimulated using a custom designed finger pad, during electrocorticographic monitoring. A cluster-based statistical analysis was then performed to localize the elicited activity on the recording grids. Mid-Gamma clusters (65-115Hz) arose in areas consistent with anatomical predictions as well as clinical findings, with five subjects presenting a somatotopic organization of the fingers. This process allowed us to delineate finger representation even in patients who were sleeping, with strong interictal activity, or when electrical stimulation did not successfully locate eloquent areas. We suggest that this scheme, relying on the endogenous neural response rather than exogenous electrical activation, could eventually be extended to map other sensory areas and provide a faster and more objective map to better anticipate outcomes of surgical resection.

Liver function, paraclinical tests, and mortality risk factors in pediatric liver transplant candidates

Liver transplantation has become a well-recognized transplant modality for children with end-stage liver disease. The first indicator to evaluate its efficiency is mortality rate. The aim of this study is to evaluate the complications and mortality of liver disease in children waiting for transplantation and understanding the risk factors that predict liver transplant waiting list death. This is a single-center prospective cohort study of all patient ≤18 years of age with chronic liver disease listed for liver transplantation. We analyzed medical records of 130 children for mortality risk factor. There were 52.3 % boys and 47.7 % girls with mean age of 8.6 ± 6.1 year (range, 3 months–18 year). The most common causes of cirrhosis were biliary atresia (21.5 %). The most common complication while awaiting transplantation was failure to thrive (76.2 %). Up to end of study, 20 patients (15.4 %) died without transplantation, 22 (16.9 %) of them transplanted, and 88 (67.7 %) of patients were alive while waiting for a liver transplantation. Mortality rate and transplantation ratio were 15.4 and 16.9 % with survival time waiting list 67.7 %. Factors which significantly associated with waiting list mortality included encephalopathy (p = 0.006), child score ≥10 (p = 0.036), model for end-stage liver disease (MELD) score ≥20 (p = 0.002), gastrointestinal bleeding (p = 0.004), Na (p = 0.046), and international normalized ratio (INR) (p = 0.018). A pediatric risk factor = (0.715 × Encephalopathy) + (0.152 × INR) − (0.022 × Na) was created. It had 90-day survival time 76.5 % for low risk group and 40.6 % for high risk group (p = 0.001) with ROC curve area 0.7 (95 % CI 0.599–0.796). The pediatric risk score such as MELD predicts the risk of liver transplantation waiting list mortality. Use of such scores in organ allocation in Iranian liver transplant unit may result in reduced waiting list mortality.

Delayed-onset hearing loss in pediatric candidates for cochlear implantation.

The objective of this study was to evaluate the clinical significance of delayed-onset hearing loss in children. Seventy-three children who underwent cochlear implantation (CI) were included. They were divided into a congenital hearing loss group (n = 50) and a delayed-onset hearing loss group (n = 23). The age at diagnosis of hearing loss, age at the beginning of auditory habilitation, the age at CI, and the postimplant speech perception abilities were compared between the two groups. Children in the congenital hearing loss group were confirmed to have hearing loss at a mean age of 0.3 years, and those in the delayed-onset hearing loss group were diagnosed with hearing loss at a mean age of 2.0 years. Auditory habilitation began at a mean age of 0.4 and 2.0 years, and CI was performed at a mean age of 1.4 and 2.6 years, respectively. Children in the congenital hearing loss group had better scores on speech perception tests than those in the delayed-onset hearing loss group, but the differences were not significant. About half of the children with delayed-onset hearing loss (57 %) had risk factors associated with delayed-onset hearing loss. A high prevalence of delayed-onset hearing loss was noted in the group of children who underwent CI. Risk factors for hearing loss were not found in 43 % of children with delayed-onset hearing loss. Universal screening for delayed-onset hearing loss needs to be performed during early childhood.

(31) - Comparison of Transplant Waitlist Outcomes for Pediatric Candidates Supported By Ventricular Assist Devices vs. Medical Therapy Alone

(31) - Comparison of Transplant Waitlist Outcomes for Pediatric Candidates Supported By Ventricular Assist Devices vs. Medical Therapy Alone

Effectiveness and safety of immunization with live-attenuated and inactivated vaccines for pediatric liver transplantation recipients

BackgroundLiver transplantation recipients are at high risk for severe complications due to infections because of being treated with immunosuppressive drugs that affect the immune system. Vaccination for liver transplantation candidates is generally recommended before surgery, but the opportunities for vaccination prior to transplantation in pediatric candidates are often limited by severe disease conditions. MethodsThe participants in this study comprised 39 pediatric recipients of living donor liver transplantation performed between 2005 and 2013. Criteria for administering live-attenuated (measles, rubella, mumps, and varicella) and inactivated (hepatitis B, pertussis, and Japanese encephalitis) vaccines were as follows: (1) >1 year after transplantation; (2) no use of systemic steroids to treat acute rejection within the last 6 months; (3) serum trough concentration of tacrolimus <5ng/mL; (4) no severe immunosuppression according to blood examinations; and (5) provision of written informed consent. Median age at transplantation was 17 months, and median period from transplantation to the beginning of immunization was 18 months. ResultsSeroprotection rates for measles, rubella, mumps, varicella, hepatitis B, pertussis, and Japanese encephalitis after post-transplant immunization were 44% (11/25), 70% (19/27), 48% (12/25), 32% (6/19), 83% (19/23), 87% (13/15), and 88% (7/8), respectively. Seroprotection rates for measles, rubella, mumps, and varicella after second vaccination for recipients with primary vaccine failure after first vaccination were 100% (8/8), 50% (1/2), 71% (5/7), and 50% (5/10), respectively. While four recipients contracted mumps and eight contracted varicella before immunization, one recipient developed varicella after immunization. No serious systemic adverse events were observed in vaccinated recipients. ConclusionsSeroprotection rates for measles, mumps, and varicella appeared low in children after the first post-transplantation vaccination. Immunizations with four live-attenuated and three inactivated vaccines were safe and effective for pediatric liver transplantation recipients who were not severely immunosuppressed.

OPTN/SRTR 2013 Annual Data Report: kidney.

A new kidney allocation system, expected to be implemented in late 2014, will characterize donors on a percent scale (0%-100%) using the kidney donor profile index (KDPI). The 20% of deceased donor kidneys with the greatest expected posttransplant longevity will be allocated first to the 20% of candidates with the best expected posttransplant survival; kidneys that are not accepted will then be offered to remaining 80% of candidates. Waiting time will start at the time of maintenance dialysis initiation (even if before listing) or at the time of listing with an estimated glomerular filtration rate of 20 mL/min/1.73 m(2) or less. Under the current system, the number of candidates on the waiting list continues to increase, as each year more candidates are added than are removed. Median waiting times for adults increased from 3 years in 2003 to more than 4.5 years in 2009. Donation rates have not increased. Short-term outcomes continue to improve; death-censored graft survival at 90 days posttransplant was 97% or higher for deceased donor transplants and over 99% for living donor transplants. In 2013, 883 pediatric candidates were added to the waiting list; 65.8% of pediatric candidates on the list in 2013 underwent deceased donor transplant. Five-year graft survival was highest for living donor recipients aged younger than 11 years (89%) and lowest for deceased donor recipients aged 11 to 17 years (68%).

OPTN/SRTR 2013 Annual Data Report: heart.

The number of heart transplants performed annually continues to increase gradually, and the number of adult candidates on the waiting list increased by 34.2% from 2003 to 2013. The heart transplant rate among active adult candidates peaked at 149.0 per 100 waitlist years in 2007 and has been declining since then; in 2013, the rate was 87.4 heart transplants per 100 active waitlist years. Increased waiting times do not appear to be correlated with an overall increase in waitlist mortality. Since 2008, the proportion of patients on life support before transplant increased from 53.4% to 65.8% in 2013. Medical urgency categories have become less distinct, with most patients listed in higher urgency categories. Approximately 500 pediatric candidates are added to the waiting list each year; the number of pediatric transplants performed each year increased from 293 in 2003 to 411 in 2013. Patient survival among pediatric recipients continues to improve; 5-year patient survival for transplants performed from 2001 through 2008 was 70% to 80%. Medicare paid for some or all of the care for 42.2% of all heart transplant recipients in 2012.

OPTN/SRTR 2013 Annual Data Report: liver.

During 2013, 10,479 adult candidates were added to the liver transplant waiting list, compared with 10,185 in 2012; 5921 liver transplants were performed, and 211 of the transplanted organs were from living donors. As of December 31, 2013, 15,027 candidates were registered on the waiting list, including 12,407 in active status. The most significant change in allocation policy affecting liver waitlist trends in 2013 was the Share 35 policy, whereby organs from an entire region are available to candidates with model for end-stage liver disease scores of 35 or higher. Median waiting time for such candidates decreased dramatically, from 14.0 months in 2012 to 1.4 months in 2013, but the effect on waitlist mortality is unknown. The number of new active pediatric candidates added to the liver transplant waiting list increased to 693 in 2013. Transplant rates were highest for candidates aged younger than 1 year (275.6 per 100 waitlist years) and lowest for candidates aged 11 to 17 years (97.0 per 100 waitlist years). Five-year graft survival was 71.7% for recipients aged younger than 1 year, 74.9% for ages 1 to 5 years, 78.9% ages 6 to 10 years, and 77.4% for ages 11 to 17 years.