Steroid-free chronic immunosuppression in renal transplantation:

Metabolic Surgery to Treat Obesity in Diabetic Kidney Disease, Chronic Kidney Disease, and End-Stage Kidney Disease; What Are the Unanswered Questions?

Obesity is a major factor in contemporary clinical practice in nephrology. Obesity accelerates the progression of both diabetic and non-diabetic chronic kidney disease and, in renal transplantation, both recipient and donor obesity increase the risk of allograft complications. Obesity is thus a major driver of renal disease progression and a barrier to deceased and living donor kidney transplantation. Large observational studies have highlighted that metabolic surgery reduces the incidence of albuminuria, slows chronic kidney disease progression, and reduces the incidence of end-stage kidney disease over extended follow-up in people with and without type 2 diabetes. The surgical treatment of obesity and its metabolic sequelae has therefore the potential to improve management of diabetic and non-diabetic chronic kidney disease and aid in the slowing of renal decline toward end-stage kidney disease. In the context of patients with end-stage kidney disease, although complications of metabolic surgery are higher, absolute event rates are low and it remains a safe intervention in this population. Pre-transplant metabolic surgery increases access to kidney transplantation in people with obesity and end-stage kidney disease. Metabolic surgery also improves management of metabolic complications post-kidney transplantation, including new-onset diabetes. Procedure selection may be critical to mitigate the risks of oxalate nephropathy and disruption to immunosuppressant pharmacokinetics. Metabolic surgery may also have a role in the treatment of donor obesity, which could increase the living kidney donor pool with potential downstream impact on kidney paired exchange programmes. The present paper provides a comprehensive coverage of the literature concerning renal outcomes in clinical studies of metabolic surgery and integrates findings from relevant mechanistic pre-clinical studies. In so doing the key unanswered questions for the field are brought to the fore for discussion.

Lung Transplantation and Precision Medicine

Lung transplantation is an accepted therapeutic option for end-stage lung diseases. Its history starts in the 1940s, initially hampered by early deaths due to perioperative problems and acute rejection. Improvement of surgical techniques and the introduction of immunosuppressive drugs resulted in longer survival. Chronic lung allograft dysfunction (CLAD), a new complication appeared and remains the most serious complication today. CLAD, the main reason why survival after lung transplantation is impaired compared to other solid-organ transplantations is characterized by a gradually increasing shortness of breath, reflected in a deterioration of pulmonary function status, respiratory insufficiency and possibly death.

Managing transplant rejection in the elderly: the benefits of less aggressive immunosuppressive regimens

Organ transplantation is increasingly common in the older population, particularly among end-stage renal disease patients. The outcomes of transplantation are often inferior in older people compared with younger recipients, partly because of the side effects of immunosuppressive medication used after organ transplantation. In this paper, we explore treatment considerations for older transplant patients. The current commonly used immunosuppressive protocols have not been validated sufficiently in older organ recipients. The primary objective for the management of transplant recipients of all ages is to prevent rejection without increasing the risk of infection or other long-term complications. To avoid serious side effects related to immunosuppressive treatment, the clinician should consider modifying and tailoring the long-term regimen for individual patients. Modifications for older recipients include reduction in the dosage or avoidance of calcineurin inhibitors, with or without the introduction of a mammalian target of rapamycin inhibitor and discontinuing the use of corticosteroids. Such modifications must consider the individual risks and needs of each recipient. Treatment of an acute rejection episode should follow the same protocol as for younger recipients, but special attention is needed to ensure reduction in the total immunosuppressive load. One way to achieve this is to avoid anti-thymocyte globulin (ATG) induction and to use on-demand ATG treatment of rejection on the basis of the patient's CD3 T cell count.

Filtering lymphocytes may decrease the need for immunosuppression in solid organ transplantation

Organ transplantation has become very important for patients with irreversible organ diseases. The transplanted organ is foreign to the host and, therefore, it induces a complex immune response of the patient. Therefore, Immunosuppressive agents are usually required to suppress both specific and nonspecific immunity and prevent allograft rejection in recipients who undergo organ transplantation. Of the late years, newer immunosuppressive agents with non-overlapping toxicities have been used in combinations in order to provide better patient and graft survival. However, these medications are associated with significant adverse effects that impact quality of life and sometimes long-term survival of the patient. Adverse effects can differ between the immunosuppressants, but many result from the overall state of immunosuppression. Strategies to manage immunosuppressant adverse effects often involve minimizing exposure to the drugs while balancing the risk for rejection. However, to prevent rejection of the transplanted organ, there may be unproven approaches other than immunosuppressive drugs. Filtering lymphocytes by a specific filter with respect to their size can be an alternative way. Our hypothesis was concerning of if such a filter could manage this and take the place of these drugs.