Mycophenolate mofetil in pediatric liver transplant patients with renal dysfunction: preliminary data

Side effects and efficacy of renal sparing immunosuppression in pediatric liver transplantation-A single center matched cohort study

Immunosuppressive combination therapy with MMF can reduce CNI associated nephrotoxicity. We investigated effectiveness and safety of de novo MMF-tacrolimus based immunosuppression after pLTx. Patients after pLTx receiving immunosuppression with MMF/tacrolimus (MMF/TAC) were compared to retrospectively selected age- and diagnosis-matched patients with tacrolimus monotherapy (TAC) and cyclosporine/prednisolone therapy (CSA) (19 patients each, n = 57). Effectiveness, renal function and side effects were analyzed for 1 year after pLTx. Tacrolimus reduction in combination therapy (0.7 μg/L over the year) was lower than aspired (2 μg/L). Acute BPAR occurred equally in MMF/TAC and TAC groups (31.6% each), being slightly higher in CSA group (42.1%; OR = 1.5; 95% CI = 0.42-5.44; P = .5). GFR deteriorated comparably in all 3 groups (P < .01 each) without significant differences between the groups. Septicemia was detected significantly more often in MMF/TAC (73.6%) than in TAC (31.6%) (OR 4.17; 1.07-16.27; P = .04). EBV reactivation occurred more often in CSA patients (84.2%) than in MMF/TAC (47.4%; OR 5.16; 0.98-27.19; P = .05) and TAC patients (52.6%; OR 8.16; 1.48-44.89; P = .02) the same was true for other viral infections (47.4% (CSA) vs 15.8% (TAC); OR 4.21; 0.95-18.55; P = .05). Our study does not provide additional evidence for a benefit of initial use of MMF/TAC over TAC regarding renal function, but raises concerns regarding a potentially increased risk of serious infections under MMF/TAC compared to TAC monotherapy at equivalent renal outcome; our study is, however, limited by the minor CNI reduction in combination therapy.

The adolescent and liver transplantation

The outcome of liver transplantation is usually reported in terms of graft and patient survival, medical and surgical complications, and quality of life, but when it comes to transplanted adolescents such conventional parameters are unable to give a full account of their life with a new liver, and their transition from adolescence to adulthood is a time when they are particularly vulnerable. Adolescents with liver transplants have excellent survival rates, over 80% of them surviving more than 10 years. Graft loss is most often associated with complications such as chronic rejection, hepatic artery thrombosis, and biliary complications. Calcineurin inhibitors may have various side effects, including hypertension and nephrotoxicity. Liver-transplanted adolescents are also exposed to viral infections, among which Epstein-Barr virus is very common and associated with the onset of post-transplant lymphoproliferative disorders. Growth retardation may also be an issue in some liver transplant recipients. Future studies will determine the best way to assess the functional immune status of adolescents with a transplanted liver with a view to ensuring the best treatment to induce tolerance without the complications of excessive immunosuppression. Schooling may be disrupted due to adolescent transplant recipients' poor adherence. Non-adherence is associated with a poor medical outcome. Both physical and psychosocial functioning is reportedly lower among young liver transplant recipients than in the general population.

Liver transplantation in Greek children: 15 years experience

Liver transplantation (LT) is the only available live-saving procedure for children with irreversible liver failure. This paper reports our experience from the follow-up of 16 Greek children with end-stage liver failure who underwent a LT. Over a period of 15 years, 16 pediatric liver recipients received follow up after being subjected to OLT (orthotopic liver transplantation) due to end-stage liver failure. Nine children initially presented with extrahepatic biliary atresia, 2 with acute liver failure after toxic mushroom ingestion, 2 with intrahepatic cholestasis, 2 with metabolic diseases and one with hepatoblastoma. Ten children received a liver transplant in the Organ Transplantation Unit of Aristotle University of Thessaloniki and the rest in other transplant centers. Three transplants came from a living-related donor and 13 from a deceased donor. Six children underwent immunosuppressive treatment with cyclosporine, mycophenolate mofetil and corticosteroids, and 7 with tacrolimus, mycophenolate mofetil and corticosteroids. Three out of 16 children died within the first month after the transplantation due to post-transplant complications. Three children presented with acute rejection and one with chronic organ rejection which was successfully managed. Five children presented with cytomegalovirus infection, 5 with Epstein-Barr virus, 2 with HSV(1,2), 2 with ParvoB19 virus, 2 with varicella-zoster virus and one with C. Albicans infection. One child presented with upper gastrointestinal hemorrhage and one with small biliary paucity. A satisfying outcome was achieved in most cases, with good graft function, except for the patient with small biliary paucity who required re-transplantation.The long-term clinical course of liver transplanted children is good under the condition that they are attended in specialized centers.

Calcineurin inhibitor-sparing regimens in solid organ transplantation: focus on improving renal function and nephrotoxicity

BACKGROUND

The calcineurin inhibitors (CNIs), cyclosporine and tacrolimus, have had a revolutionary effect on the overall success of renal transplantation through reduction in early immunologic injury and acute rejection rates. However, the CNIs have a significant adverse impact on renal function and cardiovascular disease, and extended long-term graft survival has not been achieved. The recognition of these effects sparked interest in CNI-sparing strategies. Strategies to limit CNI exposure include CNI minimization, avoidance, and withdrawal. We sought to review the impact of CNI-sparing strategies in kidney, liver, and heart transplantation.

MATERIALS AND METHODS

A PubMed search 1966 to August 2006 was conducted to identify relevant research articles, and the references of these articles as well as the authors' personal files were reviewed.

RESULTS

Calcineurin inhibitor minimization using mycophenolate mofetil or sirolimus may be associated with a modest increase in creatinine clearance (CrCl) and a decrease in serum creatinine (SCr) in the short term. Despite improvement in CrCl or SCr, CNI nephrotoxicity and chronic allograft nephrotoxicity are progressive over time when CNI exposure is maintained. In kidney transplantation, the tubulo-interstitial and glomerular damage are irreversible. Mycophenolate mofetil may improve renal outcomes during CNI minimization more than sirolimus, and antibody induction may be effective to limit CNI exposure, but longer-term follow-up data are required. Use of sirolimus with mycophenolate mofetil or azathioprine to avoid CNI exposure de novo has improved glomerular filtration rate for at least two yr in most studies in kidney transplantation; however, experience is limited in liver and heart transplantation, and reports of delayed graft function and wound healing with sirolimus may have dampened enthusiasm for de novo use. Late CNI withdrawal has achieved variable results, possibly because withdrawal was attempted after the kidney damage was too extensive. Early CNI withdrawal, prior to significant graft damage, has generally improved CrCl and markers of fibrosis and decreased chronic allograft lesions, a finding also observed with sirolimus in most CNI avoidance studies. Successful withdrawal appears to be more effective than CNI minimization.

CONCLUSIONS

Calcineurin inhibitors are associated with significant nephrotoxicity and chronic kidney damage. Minimization is associated with a modest increase in renal function, but persistent damage is observed on biopsies as long as the CNIs are continued. Avoidance is hampered by lack of experience and possible sirolimus-induced side effects. CNI withdrawal may be the best option by delivering CNIs during the early period of immunologic graft injury and then converting them to less nephrotoxic agents before significant renal damage occurs.

Mycophenolate mofetil promotes prolonged improvement of renal dysfunction after pediatric liver transplantation: experience of a single center

Few studies have evaluated the long-term use of MMF in liver transplanted children with renal dysfunction. The aim of this study is to report the experience of a pediatric transplantation center on the efficacy and security of long-term use of a MMF immunosuppressant protocol with reduced doses of CNIs in stable liver transplanted children with renal dysfunction secondary to prolonged use of CsA or Tac. Between 1988 and 2003, 191 children underwent OLT and 11 patients developed renal dysfunction secondary to CNIs toxicity as evaluated by biochemical renal function parameters. The interval between liver transplantation and the introduction of the protocol varied from one to 12 yr. Renal function was evaluated by biochemical parameters in five phases: immediately prior to MMF administration; 3, 6, 12 and 24 months after the introduction of MMF. Among the patients, nine of them (82%) showed improvement of renal function parameters in comparison with the pretreatment values. The two patients that did not show any improvement were patients in whom the interval of time between OLT and the introduction of MMF was longer. All parameters of liver function remained unchanged. No episodes of acute or chronic rejection or increases in infection rates during the period were detected. Two patients developed transitory diarrhea and leukopenia that were reverted with reduction of MMF dosage. In conclusion, in liver transplanted pediatric patients with CNI-induced chronic renal dysfunction, the administration of MMF in addition to reduced doses of CNIs promotes long-term improvement in renal function parameters with no additional risks.

Mycophenolate mofetil in organ transplantation: focus on metabolism, safety and tolerability

Mycophenolate mofetil (MMF) received its first approval for the prevention of renal allograft rejection in 1995 and has now become the most frequently used antiproliferative agent in maintenance immunosuppressive therapy for kidney, pancreas, liver and heart transplantation. In addition, its use for the treatment of autoimmune diseases steadily increases. This review focuses on the miscellaneous pharmacodynamic properties of the drug, its pharmacokinetics in healthy subjects, recipients of different organ transplants and combination therapy with other pharmaceuticals, as well as its safety profile. The immunosuppressive activity of MMF is thought to derive mainly from the potent and selective inhibition of purine synthesis in both T and B lymphocytes. In contrast to other immunosuppressants on the market, it is metabolised primarily by glucuronidation and lacks nephrotoxicity, cardiovascular toxicity or diabetogenic potential, thus making it a suitable candidate for combination regimens. The most important side effects under MMF include gastrointestinal disorders, of which the underlying mechanisms are not yet fully understood, but seem to be complex and related to both effects of mycophenolic acid and its acyl glucuronide, as well as to decreased -immunity due to general immunosuppression after transplantation.

Mycophenolate mofetil in the treatment of uveitis in children

BACKGROUND

Mycophenolate mofetil (MMF) is a new immunosuppressive agent that effectively controls the intraocular inflammation in adults.

PURPOSE

To assess the efficacy of MMF in uveitis in children and to analyse the possible side effects.

PARTICIPANTS AND METHODS

A retrospective analysis was carried out on 17 children (32 eyes) with intraocular inflammation treated with MMF and followed up at the University Eye Hospital Tuebingen, Tuebingen, Germany, between 2000 and 2005. All children had chronic non-infectious uveitis and received MMF for at least 6 months. All patients were given steroids or other immunosuppressive agents before initiating treatment with MMF.

RESULTS

17 children (10 boys and 7 girls) with a mean age of 8 (range 2-13) years at the onset of uveitis were examined. The average duration of follow-up after initiation of MMF was 3 (range 2-5) years. A steroid-sparing effect was achieved in 88% of the patients. The oral prednisolone was successfully discontinued in 41% children and reduced to a daily dose of < or =5 mg in 47% of the children. 24% of the patients remained relapse-free during the treatment, but a reduction in the relapse rate was observed in all other patients except one. Visual acuity was increased or maintained in 13 children (76%). Mild side effects (headache, rash, gastrointestinal discomfort) occurred in 7 patients (41%) and were the cause of discontinuation of MMF in 1 patient.

CONCLUSION

The results of our study are encouraging and suggest that MMF is an effective agent also in the treatment for uveitis in children, with marked steroid-sparing potential and an acceptable side effect profile.

Mycophenolate mofetil for renal dysfunction after pediatric liver transplantation

BACKGROUND

Cyclosporine A (CsA) and tacrolimus (Tac) provide effective immunosuppression after orthotopic liver transplantation (OLT) but can cause renal dysfunction that may progress to end-stage renal failure (ESRF). Mycophenolate mofetil (MMF) is a newer immunosuppressant that does not affect renal function. Its long-term use in children with renal dysfunction after OLT has not yet been fully evaluated.

METHODS

A retrospective analysis was performed of all children begun on MMF for renal dysfunction and followed up for at least 1 year. Renal dysfunction was defined as calculated glomerular filtration rate (cGFR) of less than 65 mL/min/1.73 m2. cGFR and liver function were measured before and after transfer. Data were analyzed using the Wilcoxon signed rank test.

RESULTS

Forty-eight children (23 males) began MMF at a median age of 11.1 (0.9-18.1) years and at a median of 4.0 (0.3-12.4) years postOLT. Median baseline cGFR was 54 (range 29-65) mL/min/1.73 m2. Immunosuppression after transfer was MMF monotherapy in 36, MMF with steroids, in 4 and MMF with low-dose CsA or Tac in 8. In 44 (92%) patients, there was a statistically significant increase to a median cGFR of 69 (28-114) mL/min/1.73 m2 by 1 month and a further increase to a median cGFR of 77 (24-105) mL/min/1.73 m2 by 2 months of MMF treatment, after which time cGFR was maintained. Children aged less than 3 years at OLT or who were less than 5 years postOLT when MMF was begun demonstrated greater increases in cGFR. Four children with a median baseline cGFR of 34 (range 31-49) mL/min/1.73 m2 did not respond and progressed to ESRF. Mild side effects occurred in seven (15%) and gastrointestinal bleeding requiring discontinuation of MMF in one (2%). Liver function abnormalities occurred in seven (15%): transient transaminitis in three, acute rejection in two, and chronic rejection in two, of whom one required retransplantation.

CONCLUSIONS

In 92% children with renal dysfunction after OLT, MMF treatment provided safe and effective immunosuppression and allowed CsA or Tac to be discontinued or reduced, leading to improvement of renal function. The improvement was greatest in younger children and those who began MMF early postOLT. Side effects were uncommon. Additional steroid cover during the transfer to MMF should be considered to prevent liver-allograft rejection.

Mycophenolate mofetil and reduced doses of cyclosporine in pediatric liver transplantation with chronic renal dysfunction: changes in the immune responses

The aim of this study was to study the incidence of chronic renal dysfunction in patients with more than 5 yr of follow-up following liver transplantation and to evaluate the benefit of decreasing cyclosporine A (CsA) dose combined with mycophenolate mofetil (MMF) on renal function and immune response in these patients. Between 1988 and 1994, 60 children were transplanted, and 86% survived >5 yr post-liver transplantation. Fourteen patients developed chronic renal dysfunction secondary to CsA toxicity as evaluated by renal biopsy. In 11 patients CsA dose was decreased to 40-90 mg/ml target levels and MMF 600 mg/m(2) twice daily was added to the immunosuppressive regimen. Plasma creatinine decreased (from 1.0 +/- 0.03 to 0.8 +/- 0.03 ng/dl, p < 0.007), creatinine clearance increased (from 66.8 +/- 3.0 to 99.2 +/- 6.3 ml/min/1.73 m(2), p < 0.002) and microalbuminuria decreased (from 21.0 +/- 8.6 to 3.6 +/- 1.1 mg/24 h, p < 0.05) after 12 months of CsA combined with MMF therapy. During combined therapy the proliferative, cytolytic response and cytotoxic antibodies showed no significant changes, whereas CD4/CD8 ratio increased (from 1.2 +/- 0.2 to 1.4 +/- 0.1, p < 0.05). Tumor necrosis factor-alpha secretion increased (p < 0.005) during MMF therapy. The release of interleukin-10 was strikingly augmented under both immunosuppressive regimens, but the release of transforming growth factor-beta and interferon-gamma did not change. Our findings indicate that initiation of MMF combined with reduced doses of CsA allowed the recovery of renal function with minor changes in the immune response.