Strategies for optimizing immunosuppression in adolescent transplant recipients: a focus on liver transplantation

A Rotavirus-Induced Mouse Model to Study Biliary Atresia and Neonatal Cholestasis

Biliary atresia is a devastating neonatal cholangiopathy that affects both extra- and intrahepatic bile ducts progressing to fibrosis and end-stage liver disease by 2 years of age. Despite re-establishment of biliary drainage following a Kasai portoenterostomy (surgical procedure), many infants develop fibrosis requiring liver transplant. In the murine model of biliary atresia, rhesus rotavirus infection of newborn pups results in a cholangiopathy paralleling human biliary atresia and is used to study mechanistic aspects of the disease. The infected mice displayed histopathological signs similar to human biliary atresia, with bile duct obstruction, bile duct proliferation, and liver inflammation with fibrosis.

Lung Transplantation in Adolescents and Young Adults with Cystic Fibrosis

Context

Little is known about adolescents' and young adults' experience with cystic fibrosis while waiting for or after receiving a lung transplant. The psychological and psychosocial factors that may influence these patients' transplant outcomes are yet to be fully explored.

Objective

To explore the psychosocial impact of the lung transplant journey on adolescents and young adults with cystic fibrosis.

Design

A questionnaire-based pilot study was used to enable descriptive, comparative, and correlational analyses between pretransplant and posttransplant groups. Setting—A major lung transplant unit in Australia.

Participants

Twenty-seven patients (9 before and 18 after transplantation) participated in the study. The mean ages were 18.7 years (SD 4.2) and 22.6 years (SD 3.9) in the pretransplant and posttransplant groups, respectively.

Results

In all domains of the Short Form 36 except Mental Health and Social Functioning, the posttransplant group had significantly higher scores ( P < .05) compared to the pretransplant group. The Hospital and Anxiety and Depression Scale total Distress score in the posttransplant group was related to the number of rejection episodes ( r = 0.47, P = .049) as well as hospital admissions ( r = 0.51, P = .012). The number of rejection episodes was significantly related to patients' perceived level of self-efficacy ( P = .025), importance to health ( P = .001), and ease ( P = .10) of monitoring their symptoms.

Conclusion

This study provides some insight into the needs of adolescents and young adults with cystic fibrosis and the differences between those who are awaiting a transplant and those who have received a transplant. Assessing the young person's perceptions in relation to activities such as exercising, monitoring symptoms, and taking medications can give helpful insights into the transition phase, but require further research.

Newborn Screening for Biliary Atresia

Biliary atresia is the most common cause of pediatric end-stage liver disease and the leading indication for pediatric liver transplantation. Affected infants exhibit evidence of biliary obstruction within the first few weeks after birth. Early diagnosis and successful surgical drainage of bile are associated with greater survival with the child's native liver. Unfortunately, because noncholestatic jaundice is extremely common in early infancy, it is difficult to identify the rare infant with cholestatic jaundice who has biliary atresia. Hence, the need for timely diagnosis of this disease warrants a discussion of the feasibility of screening for biliary atresia to improve outcomes. Herein, newborn screening for biliary atresia in the United States is assessed by using criteria established by the Discretionary Advisory Committee on Heritable Disorders in Newborns and Children. Published analyses indicate that newborn screening for biliary atresia by using serum bilirubin concentrations or stool color cards is potentially life-saving and cost-effective. Further studies are necessary to evaluate the feasibility, effectiveness, and costs of potential screening strategies for early identification of biliary atresia in the United States.

Health-related quality of life, treatment adherence, symptom experience and depression in adolescent renal transplant patients

Few studies comprehensively assessed psychological and behavioral functioning in adolescent kidney transplant patients. The purpose of this cross-sectional study was to evaluate depression, QOL, treatment adherence and presence of side effects from the perspective of the patient and his parents, and to compare scores with norm data. All patients (age 10-18 yr) and their parents completed the following instruments: KIDSCREEN-27 (QOL), a treatment adherence interview, the MTSOSD-59R (side effects) and the Beck Depression Inventory (depression). Twenty-three of 26 patients and 22 parents agreed to participate (70% male; median age 15 yr). Adolescents rated their QOL as satisfactory, but parents reported significant problems on several QOL dimensions. Depressive symptoms occurred in 17.4%, and 75% were non-adherent with their immunosuppressive drugs (confirmed by their parents) and show other problematic health behavior, including smoking, illicit drug use, dietary non-adherence, and suboptimal exercise levels. The most frequently occurring side effects were increased appetite, fatigue and headache; the most distressing ones were hair loss or thinning of hair, warts on hands or feet, and sores in the mouth or on the lips. Our results underscore the need for regular screening and adequate treatment of the above-mentioned aspects.

Meta-analysis of medical regimen adherence outcomes in pediatric solid organ transplantation

BACKGROUND

Adherence to the medical regimen after pediatric organ transplantation is important for maximizing good clinical outcomes. However, the literature provides inconsistent evidence regarding prevalence and risk factors for nonadherence posttransplant.

METHODS

A total of 61 studies (30 kidney, 18 liver, 8 heart, 2 lung/heart-lung, and 3 with mixed recipient samples) were included in a meta-analysis. Average rates of nonadherence to six areas of the regimen, and correlations of potential risk factors with nonadherence, were calculated.

RESULTS

Across all types of transplantation, nonadherence to clinic appointments and tests was most prevalent, at 12.9 cases per 100 patients per year (PPY). The immunosuppression nonadherence rate was six cases per 100 PPY. Nonadherence to substance use restrictions, diet, exercise, and other healthcare requirements ranged from 0.6 to 8 cases per 100 PPY. Only the rate of nonadherence to clinic appointments and tests varied by transplant type: heart recipients had the lowest rate (4.6 cases per 100 PPY vs. 12.7-18.8 cases per 100 PPY in other recipients). Older age of the child, family functioning (greater parental distress and lower family cohesion), and the child's psychological status (poorer behavioral functioning and greater distress) were among the psychosocial characteristics significantly correlated with poorer adherence. These correlations were small to modest in size (r=0.12-0.18).

CONCLUSIONS

These nonadherence rates provide benchmarks for clinicians to use to estimate patient risk. The identified psychosocial correlates of nonadherence are potential targets for intervention. Future studies should focus on improving the prediction of nonadherence risk and on testing interventions to reduce risk.

Selective retransplant after graft loss to nonadherence: success with a second chance

Nonadherence (NA) is a difficult posttransplant problem that can lead to graft loss. A retransplant is controversial because of a fear of recurrent NA. We reviewed our center's data base and identified 114 kidney recipients who lost their graft to overt NA; of this group, 35 (31%) underwent a retransplant after a thorough reevaluation. We compared this NA retransplant group to a control group of second transplant recipients who did not lose their first graft to overt NA (non-NA) (n = 552). After 8 years of follow-up, we found no significant differences between the groups in actuarial graft or patient survival rates, renal function, or the incidence of biopsy-proven chronic rejection. However, 5 of 35 (14%) NA recipients versus 10 of 552 (2%) non-NA recipients lost their retransplant to NA (p = 0.0001). Twenty of 35 (57%) of the NA group exhibited repeat NA behavior after retransplant. We conclude that prior graft loss to NA is associated with increased graft loss to NA after retransplant. However, the majority of NA retransplant recipients did well-with overall long-term outcomes similar to those of the non-NA group. With careful patient selection and aggressive intervention, prior overt NA should not be an absolute contraindication to retransplantation.

Biological and psychological differences in the child and adolescent transplant recipient

Solid organ transplantation has become accepted therapy for the treatment of end-stage organ dysfunction in children. As early management of the pediatric transplant recipient has improved, important age-related differences in long-term patient outcomes have become apparent. Late morbidity and mortality can, in most cases, be attributed to the consequences of long-term immunosuppression: graft loss from under-immunosuppression or an increased incidence of cancer, hypertension, renal failure or diabetes from over-immunosuppression. Age-related differences in both biological and psychological factors play an important role in the optimization of therapy in the transplanted child. Important age-related differences have been demonstrated in all phases of pharmacokinetics: absorption, distribution, metabolism and elimination. Information regarding specific age-related pharmacokinetic differences is lacking for many immunosuppressive medications. Further study using physiologically based pharmacokinetic (PBPK) models will lead to more specific recommendations for age-based immunosuppression protocols. Non-adherence is common among solid organ transplant recipients of all ages and the consequences of non-adherence include increased rejection, late graft loss and death. The biological and psychological developmental changes that occur during adolescence place the transplanted adolescent at an even higher risk of non-adherence and poor outcome than other age groups. Further studies to elucidate the importance of both age-related pharmacokinetic and behavioral factors are needed to formulate therapeutic interventions that would improve adherence and patient outcomes.

Growing pains: non-adherence with the immunosuppressive regimen in adolescent transplant recipients

One-year graft and patient survival are better in adolescent transplant recipients (age 11-19 years) than in younger (age < 11 years) pediatric transplant recipients. However, several groups found that long-term outcomes (> i.e. 5 year post-transplant) in the adolescent age group are significantly worse than in younger transplant recipients. A behavioral factor that could explain an important part of the poorer clinical outcome in adolescent transplant recipients is non-compliance with medication taking. Adolescents, like all organ transplant recipients irrespective of their age, must adhere to a life-long immunosuppressive regimen in addition to other aspects of their therapeutic regimen. Therefore, adolescent transplant recipients, as all transplant patients, should be regarded as a chronically ill patient population in whom behavioral and psychosocial management is equally important as state-of-the-art medical management. This paper provides an overview of the current knowledge on prevalence, clinical consequences, and risk-factors for non-compliance with the immunosuppressive regimen in adolescent transplant recipients and offers some suggestions for adolescent-tailored interventions to improve medication adherence.

Update on liver transplantation using cyclosporine

After the introduction of cyclosporine into liver transplantation in 1983, 1-year patient survival more than doubled. Later, with the improved microemulsified formulation of cyclosporine (Neoral) more stable pharmacokinetics were achieved. Today, C(2) monitoring of cyclosporine blood levels allows a more accurate estimation of the area under the concentration-versus-time curve as the single best indicator of cyclosporine exposure. As a consequence, with better control of side effects as well as desired effects the results of cyclosporine in liver transplantation have been further improved. The introduction of mycophenolate mofetil and basiliximab/daclizumab combination therapy has provided new options for the prevention of allograft rejection. The safety profile of individual immunosuppressive regimens comes more into focus since acute allograft rejection may be controlled successfully with competing strategies. As the focus in liver transplantation is shifting toward greatly improved long-term results, late posttransplant mortality with a functioning graft is a major concern. Prevention of long-term complications associated with highly effective immunosuppressants--posttransplant lymphoproliferative disease, cytomegalovirus infection, diabetes, hypertension, and hyperlipidemia-gains importance. Technical advances in living-related and cadaveric split-liver transplantation have lead to increasing use of segmental liver transplantation with the need to consider the effects of immunosuppression on liver regeneration and metabolism. The individualized orchestration of immunosuppression taking into account the underlying liver disease as well as other individual predispositions remains a future challenge.

Inhibitors of Calcineurin

Before the early 1980s, patient and allograft survival for solid organ transplant recipients was dismal. By 1983, the first calcineurin blocker, cyclosporine (Sandimmun), had been introduced, and outcomes were dramatically improved. However, cyclosporine macroemulsion had suboptimal pharmacokinetics, significant drug interactions, and several adverse effects, including nephrotoxicity, neurotoxicity, hyperlipidemia, and hypertension. Recent advances with cyclosporine include the introduction of modified dosage formulations: Neoral, a microemulsion, and several generic microemulsion products. The potent second-generation calcineurin blocker tacrolimus (Prograf) was introduced in 1994 and has become the drug of choice for several types of transplant recipients. Although tacrolimus has improved pharmacokinetics and therapeutic drugmonitoring parameters, it has adverse effects such as nephrotoxicity, neurotoxicity, and diabetes. Thus, current immunosuppressive regimens implementing calcineurin blockers often involve additional immunosuppressive agents to “spare” the use of these agents, minimizing their adverse effects. This article reviews the mechanisms of action, pharmacokinetics, clinical use, therapeutic drug monitoring, drug interactions, adverse effects, and dosing of cyclosporine and tacrolimus in solid organ transplant recipients.