Corticosteroid-sparing strategies in renal transplantation: are we still balancing rejection risk with improved tolerability?

Chronic allograft nephropathy and death with a functioning graft (mainly due to cardiovascular causes) are the most common causes of graft loss after the first year of renal transplantation. Immunosuppressants, and corticosteroids among them, contribute to an increase in cardiovascular risk because of their significant adverse effects, including hypertension, hyperlipidaemia and hyperglycaemia. Thus, corticosteroid discontinuation or avoidance has become a priority among the transplant community in order to enhance long-term graft and patient survival. Nevertheless, corticosteroid-sparing strategies may increase the risk of acute and chronic rejection and, thus, worsen the prognosis of transplant recipients. Initial attempts during the azathioprine epoch did not provide satisfactory results, as they were associated with high acute rejection rates, emphasising the risk of under-immunosuppression. The advent of new immunosuppressants, such as mycophenolate mofetil, mTOR inhibitors and anti-interleukin-2 receptor antibodies, have renewed the interest in corticosteroid-sparing protocols, and the results of new trials suggest that these corticosteroid-sparing strategies, even at an early stage after transplantation, are safe enough in view of the stable renal function and low rates of acute rejection reported. However, immunological risk factors, such as African American ethnicity, the presence of panel-reactive anti-HLA antibodies (even at low rates), and a history of previous acute rejection episodes should be taken into account and corticosteroid withdrawal strategies should be undertaken with caution. Long-term follow-up studies must be performed to confirm the encouraging short-term data.