Growth hormone is not safe for children with renal transplants

Special Considerations in Pediatric Kidney Transplantation

Universally accepted as the treatment of choice for children needing renal replacement therapy, kidney transplantation affords children the opportunity for an improved quality of life over dialysis therapy. Immunologic and surgical advances over the last 15 years have improved the pediatric patient and kidney graft survival. Unique to pediatrics, congenital genitourinary anomalies are the most common primary diseases leading to kidney failure, many with urological issues. Early urological evaluation for post-transplant bladder dysfunction and emphasis on immunization adherence are the mainstays of pediatric pretransplant and post-transplant evaluations. A child's height can be challenging, sometimes requiring an intra-abdominally placed graft, particularly if the patient is <20 kg. Maintenance immunosuppression regimens are similar to adult kidney graft recipients, although distinctive pharmacokinetics may change dosing intervals in children from twice a day to thrice a day. Viral infections and secondary malignancies are problematic for children relative to adults. Current trends to reduce/remove corticosteroid therapy from post-transplant protocols have produced improved linear growth with less steroid toxicity; although these studies are still ongoing, graft function and survival are considered acceptable. Finally, all children with a kidney transplant need a smooth transition to adult clinics. Future research in pertinent psychosocial aspects and continued technological advances will only serve to optimize the transition process. Although some aspects of kidney transplantation are similar in children and adults, for instance immunosuppression and immunosuppressive regimens, and rejection mechanisms and their diagnosis using the Banff criteria, there are important differences this review will focus on and which continue to drive innovation.

Growth after organ transplantation

Growth is an important feature of childhood, but it is usually impaired before and after organ transplantation. Modest catch-up growth often occurs after renal transplantation. Nevertheless, patients remain short due to the effects of steroids used for immunosuppression. Children with chronic liver failure are also growth impaired, although not to the same extent. They also frequently have poor catch up growth after transplantation, again due to steroids. There are several randomized controlled clinical trials reporting growth hormone (GH) use after renal transplantation. These consistently show a beneficial effect of GH on linear growth. Patients with histories of frequent acute rejections before GH may have increased risk of acute rejection during treatment. Few data exist on liver transplant patients, although GH also appears effective. GH use may be safe and effective for renal transplant recipients who have been stable without acute rejection episodes. There needs to be long-term study of GH use in liver and renal transplant patients. It is critical to focus efforts on improving growth in renal failure before transplantation through GH use and to improve posttransplant growth in all recipients by minimizing steroid exposure.

Longitudinal Analysis of T???Helper Cell Phenotypes in Renal-Transplant Recipients Undergoing Growth Hormone Therapy

BACKGROUND

Treatment with recombinant human growth hormone (rhGH) in growth-retarded children after renal transplantation is effective, but there have been concerns regarding the safety of rhGH because of its possible immunomodulatory actions. We therefore evaluated the immune phenotypes of pediatric renal-transplant recipients and controls in response to rhGH with regard to a possible shift toward a T-helper (TH)1-type response.

METHODS

Intracellular cytokines, activation markers, costimulatory, and adhesion molecules were studied in 13 children after renal transplantation (Tx+GH). Children with chronic renal failure (CRF+GH, n=11) before and under rhGH therapy and pediatric renal-transplant recipients without rhGH therapy (Tx, n=33) served as controls. Measurements were performed by four-color flow cytometry before and 4, 12, 18 and 24 weeks after initiation of rhGH therapy.

RESULTS

Under baseline conditions, Tx+GH patients did not differ from Tx patients. During rhGH therapy in children with transplants, interleukin (IL)-2 production increased threefold at 4 weeks, and IL-4 and IL-13 increased by 70% at 12 weeks. All three cytokines returned to baseline after 18 weeks. No patient experienced rejection. In CRF+GH patients, baseline values for all investigated cytokines were higher than in patients with transplants but did not change in response to rhGH therapy.

CONCLUSION

Our data indicates that rhGH therapy in stable, pediatric renal-transplant recipients has a mild and transient immunostimulatory effect in vivo. Immunosuppression and graft function in patients with transplants undergoing rhGH treatment should therefore carefully be monitored.

Current status of kidney transplant: update 2003

Pediatric transplantation has seen remarkable advances over the past two decades with reduced morbidity and mortality, reduced rejection rates, and improved long-term patient and allograft survival. Infants currently have short-term patient and allograft survival rates better than any other age group; short-term allograft survival rates in CD recipients are equal to those in LD recipients. With decreased rejection, long-term allograft survival is improving dramatically. Transplantation allows for much reduced risks and improved metabolic status, growth and development, and more normal social interactions. The future of transplantation continues to be exciting, with opportunities for reduced immunosuppressive medications and their side effects, and the elusive goal of transplantation tolerance seems within reach.

[Critical evaluation of growth hormone treatment in children with chronic renal insufficiency]

Growth failure remains a major complication of chronic renal insufficiency in children, which greatly affects their quality of life. Based upon the data published in the literature it appears that growth hormone therapy improves growth in these children, with little secondary effects. However, some uncertainties persist concerning the safety and efficacy of this therapy, so that careful evaluations must continue.