Steroid-free immunosuppression after liver transplantation does not increase the risk of graft fibrosis

Transient Elastography for Noninvasive Evaluation of Posttransplant Liver Graft Fibrosis in Turkish Children, Ege University Children Hospital Experience

OBJECTIVES

The influence of advancing fibrosis on graft survival in the context of pediatric liver transplantation accentuates the critical role of protocol-driven liver biopsies, a practice adopted by numerous medical centers. Consequently, the exigency for noninvasive methodologies to assess graft fibrosis assumes heightened importance when conventional clinical and laboratory parameters fail to reveal signs of liver damage.

METHODS

This study aimed to assess the reliability of transient elastography (TE) in pediatric liver transplant recipients to detect graft fibrosis and compare the results of TE in patients who underwent biopsy.

RESULTS

This prospective cohort study included liver transplanted children who underwent biopsy at Ege University Children's Hospital between October 1, 2021, and October 31, 2022, and a healthy control group. According to TE, fibrosis was detected in 40 patients, and no fibrosis was detected in 50. The median time to develop fibrosis was 100 months (95% CI [83.1-116.8]). A statistically significant positive correlation existed between LSM and METAVIR fibrosis score (r = 0.562, p = 0.001). There was a statistically significant difference in LSM between patients with F2 fibrosis (7.8-8.8 kPa ± 3.2) compared to patients with F0 fibrosis (5.2 kPa ± 0.7) (p = 0.005) and F1 fibrosis (6.1 kPa ± 1.5) (p = 0.041), on ANOVA.

CONCLUSION

Liver allograft fibrosis is common in long-term follow-up in children who have undergone liver transplantation. Abnormal TE may guide physicians to consider liver biopsy to detect late allograft fibrosis in these children.

Current strategies for immunosuppression following liver transplantation

BACKGROUND

New strategies for immunosuppression (IS) after liver transplantation (LTx) are in part responsible for the increased patient and graft survival seen over time. With a few basic exceptions-notably the continued use of steroids and calcineurin inhibitors (CNIs)-IS drugs and regimens being used today are different from those used 30 years ago. While graft loss due to acute or chronic rejection has become rare, the side effect burden of IS drugs exerts a significant toll on patients.

CONCEPTS/TRENDS

CNIs continue to form the backbone of IS regimens, although their use is hampered by nephrotoxicity and other adverse effects. Consequently, a variety of CNI reduction or withdrawal strategies have formed the basis of clinical trials or entered into clinical practice. These trials have included the use of everolimus, an mTOR inhibitor, and anti-interleukin-2 receptor antibodies. Basiliximab, as well as other lymphocyte nondepleting and depleting agents, have shown benefit in induction regimens.

SUMMARY

Along with steroid reduction or elimination, current strategies for IS after LTx continue to explore novel combinations of agents, with an aim toward striking a balance between diminution of rejection and the need for avoiding adverse effects of the IS drugs. Long-term maintenance strategies are also discussed in this review, as is development of tolerance and antibody-mediated rejection.

Evolving concepts in the selection of immunosuppression regimen for liver transplant recipients

The introduction of calcineurin inhibitor (CNI) based immunosuppression has revolutionized the field of liver transplantation by dramatically reducing the incidence of acute cellular rejection and prolonging patient and allograft survival. However, the introduction of CNIs has also come at the price of increased patient morbidity, particularly with regard to the well-known nephrotoxic effects of the medications. In an effort to minimize the adverse effects, immunosuppression regimen have evolved to include the use of various induction agents and purine synthesis inhibitors to limit the dose of CNI necessary to achieve low acute cellular rejection rates. Careful assessments of risks and benefits are needed as these newer agents have their own side effect profiles. In addition, the impact of newer immunosuppression regimen on hepatitis C (HCV) recurrence has not been completely elucidated. This review will provide an overview of the most common immunosuppression regimen used in liver transplantation and discuss their impact on acute cellular rejection, patient and allograft survival, and HCV recurrence.