The following issue of the „Postępy Nauk Medycznych” is dedicated to the subject of kidney transplantation in terms of internal medicine, articles were written by nephrologists – clinical transplantologists from leading Polish transplant centers involved in the chronic care of kidney recipient. We are presenting research and clinical original papers, reviews and case reports.

The number of kidney transplants in 2013 in our country amounted to 1076, in Poland, there are over 10 thousand people with kidney transplants. One of the major problems is the limited survival of kidney transplantation. As a result of the impact of immune and non-immune agents, inflammatory process occurs to be followed by interstitial tissue fibrosis and progression of renal transplant insufficiency.

The article by prof. Andrzej Oko is devoted to the pathogenesis of chronic renal allograft damage. He draws attention to the complexity of the process and shows that, in the light of new research, the main cause of chronic graft dysfunction is not, as previously thought, nephrotoxicity of calcineurin inhibitors, but the immune process of chronic humoral rejection in the transplant (AMR – antibody mediated rejection). In the biopsy image of a kidney, the presence of diffuse linear C4d deposition in the paraurethral capillaries of renal cortex and medulla is typical along with the presence of anti-HLA antibodies specific for the donor (DSA) in the recipient’s blood. The main cause of AMR is inadequate immunosuppression, often resulting from poor patient cooperation and failure to follow a regular intake of immunosuppressive drugs. Prevention and treatment of chronic humoral response is a new challenge for transplantologists.

The paper by Oktawia Mazanowska and Marian Klinger is also devoted to the pathogenesis of chronic transplant damage, they concentrate on the disorders of the extracellular matrix-degrading enzyme proteins: metalloproteinases and tissue inhibitors of metalloproteinases (MMPs/TIMPs), with greater activity of tissue inhibitors of metalloproteinases (TIMPs), which indicates a significant impairment in the processes of ECM degradation of chronic renal allograft damage. The authors believe that the tissue inhibitors of metalloproteinases (TIMPs) are a new threat indicators of the progressive loss of filtration and may be useful biomarkers in clinical practice used to monitor the recipients at a later period after kidney transplantation, when chronic graft failure begins to dominate.