[Pattern of biochemical markers of mineral and bone disorders in kidney transplant recipients: real-world data].

BACKGROUND: There is a lack of studies providing comprehensive data on the prevalence of mineral and bone disorders (MBD) laboratory abnormalities after kidney transplantation in Russia. AIM: to obtain real-world data on the prevalence of the main mineral abnormalities among kidney transplant recipients and to revise their concomitant MBD therapy. METHOD: This cross-sectional study included 236 patients with successful kidney transplantation. Their serum intact parathyroid hormone (iPTH), total calcium (Ca), phosphorus (P), and alkaline phosphatase (ALP) levels were measured. RESULTS: Only 6.2% of our cohort had all laboratory parameters within the target range, whereas persistent HPT along with hypercalcemia was noted in almost one third of the patients (31%). Normal iPTH levels were observed in 13% cases; 84% of the patients had hyperparathyroidism. The fraction of patients with target iPTH did not differ between the groups with normal and decreased estimated glomerular filtration rate (eGFR) (p=0.118). Hypercalcemia was observed in 29% cases. The serum P level varied significantly in groups with different eGFR (p<0.0001), increasing with declining graft function. Furthermore, 40.7% of patients had ALP above the target range. While 123 patients received active vitamin D (alfacalcidol), 33 received monotherapy with inactive vitamin D (cholecalciferol). The control group consisted of 57 medication-naïve patients. The serum total Ca level varied significantly between the groups (p=0.0006), being higher in patients supplemented with cholecalciferol. The fraction of patients with normocalcemia was lowest in the cholecalciferol group (chi-square, р=0.0018). CONCLUSION: The prevalence of biochemical abnormalities after kidney transplantation is high. Alfacalcidol usage may be safer than using cholecalciferol to prevent hypercalcemia development.

[Immunological monitoring of the efficacy of extracorporeal photopheresis for prevention of kidney transplant rejection].

BACKGROUND: The concept of the formation of immunological tolerance is a promising direction for correcting the renal transplant rejection. One of these methods is extracorporeal photochemotherapy (ECP), however, according to the literature, there is no single concept of its mechanisms of action in the formation of immunological tolerance in transplantology. AIM: To assess the effect of the preventive use of extracorporeal photochemotherapy on the factors of cellular immunity that contribute to the development of long-term tolerance in patients after kidney transplantation. MATERIALS AND METHODS: A total of 24 patients after a cadaveric kidney transplantation with group matching were included in the study. During the first six months after transplantation, 15 patients of the main group (MG) underwent 10 sessions of ECP in combination with the standard immunosuppression protocol, and 9 patients of the control group (CG) received only standard immunosuppressive therapy. Immunological studies were carried out by the 3rd year after transplantation. The number of cells expressing the antigens CD3, CD4, CD8, CD19, CD16 and CD56, the expression of co-stimulating molecules CD25, CD28 on T-lymphocytes, the number of T-regulatory cells with the CD3+ CD4+ CD25+ (hi) CD127- phenotype was evaluated. RESULTS: Compared with early post-transplant period, the number of naive CD3+CD4+CD45RO-CD28+ T-cells and CD28+ antigen expression was not different between two groups by 3 years after transplantation and with a group of otherwise healthy individuals (p=0.47 and p=0.26, respectively). Three years after transplantation, the T-helper lymphocyte count (CD3+CD4+) in MG were significantly higher than in CG (48.5+/-7.3% vs. 43.0+/-4.6%, respectively; p=0,04), cytotoxic T-lymphocytes count (CD3+CD8+) was 29.5+/-8.9% in MG, compared to 36.1+/-8.6% in CG (p=0.09), the ratio of CD4+/CD8+ in MG was significantly higher (1.83+/-0.72) than in CG (1.29+/-0.49) (p=0.04). CD19+ lymphocytes count was significantly below normal values in both groups, but in the CG it was more pronounced than in the MG (5.06+/-2.1% and 7.73+/-3%, respectively, (p=0.02) In the long-term period, CD3+CD4+CD25+(hi)CD127- T-regulatory cells count in MG was significantly higher than in CG (20.6+/-10.76*106/L and 12.9+/-4.97*106/l, respectively) (p=0.04). CONCLUSION: ECP initiates immunological tolerance through the activation of a second co-activation pathway between B-7 and CTLA-4 molecules in the early period after kidney transplantation. As a result, a clone of tolerogenic CD3+CD4+ T-lymphocytes is formed, which differentiates into T-regulatory cells and maintains immunological tolerance in the long-term period. Using ECP as a part of combination therapy allows to normalize the indicators of cellular immunity in the long-term period. BACKGROUND: The concept of the formation of immunological tolerance is a promising direction for correcting the renal transplant rejection. One of these methods is extracorporeal photochemotherapy (ECP), however, according to the literature, there is no single concept of its mechanisms of action in the formation of immunological tolerance in transplantology. AIM: To assess the effect of the preventive use of extracorporeal photochemotherapy on the factors of cellular immunity that contribute to the development of long-term tolerance in patients after kidney transplantation. MATERIALS AND METHODS: A total of 24 patients after a cadaveric kidney transplantation with group matching were included in the study. During the first six months after transplantation, 15 patients of the main group (MG) underwent 10 sessions of ECP in combination with the standard immunosuppression protocol, and 9 patients of the control group (CG) received only standard immunosuppressive therapy. Immunological studies were carried out by the 3rd year after transplantation. The number of cells expressing the antigens CD3, CD4, CD8, CD19, CD16 and CD56, the expression of co-stimulating molecules CD25, CD28 on T-lymphocytes, the number of T-regulatory cells with the CD3+ CD4+ CD25+ (hi) CD127- phenotype was evaluated. RESULTS: Compared with early post-transplant period, the number of naive CD3+CD4+CD45RO-CD28+ T-cells and CD28+ antigen expression was not different between two groups by 3 years after transplantation and with a group of otherwise healthy individuals (p=0.47 and p=0.26, respectively). Three years after transplantation, the T-helper lymphocyte count (CD3+CD4+) in MG were significantly higher than in CG (48.5+/-7.3% vs. 43.0+/-4.6%, respectively; p=0,04), cytotoxic T-lymphocytes count (CD3+CD8+) was 29.5+/-8.9% in MG, compared to 36.1+/-8.6% in CG (p=0.09), the ratio of CD4+/CD8+ in MG was significantly higher (1.83+/-0.72) than in CG (1.29+/-0.49) (p=0.04). CD19+ lymphocytes count was significantly below normal values in both groups, but in the CG it was more pronounced than in the MG (5.06+/-2.1% and 7.73+/-3%, respectively, (p=0.02) In the long-term period, CD3+CD4+CD25+(hi)CD127- T-regulatory cells count in MG was significantly higher than in CG (20.6+/-10.76*106/L and 12.9+/-4.97*106/l, respectively) (p=0.04). CONCLUSION: ECP initiates immunological tolerance through the activation of a second co-activation pathway between B-7 and CTLA-4 molecules in the early period after kidney transplantation. As a result, a clone of tolerogenic CD3+CD4+ T-lymphocytes is formed, which differentiates into T-regulatory cells and maintains immunological tolerance in the long-term period. Using ECP as a part of combination therapy allows to normalize the indicators of cellular immunity in the long-term period.

[The long-term infective complications in patients after kidney transplantation and photopheresis].

AIM: to evaluate the influence of prophylactic use of photopheresis on the risk of long-term infective complications after kidney transplantation. MATERIALS AND METHODS: The open cohort randomized study was conducted. A total of 60 recipients after cadaveric kidney allotransplantation from 30 donors were assessed. The patients were randomized into two groups (n=30). All transplants were paired, and one kidney was transplanted to patient in intervention group and the another one was transplanted to patient in control group. In the intervention group all patients received standard immunosuppression therapy (tacrolimus, mycophenolate, prednisone) and 10-15 sessions of photopheresis during first 6 months after the transplantation. In the control group only the immunosuppression therapy was given. The follow-up period ranged from 2 to 7 years, an average 4.5+/-2.0 years. RESULTS: The rate infective complications in the both groups gradually decreased as the postoperative period increased exponentially, but it was lower in the intervention group than in the control group. The rate of respiratory infection, asymptomatic bacteriuria and viremia, verified by the genetic amplification was 4, 2 and 1.5 times lower in the intervention group. The risk of clinically meaningful infection was significantly lower in the intervention group than in the control group: IRR 0.3888 (95% CI 0.2754; 0.5445; <0.0001). 6-year survival in the intervention group was 100% in comparison to 82.8% in the control group (95% CI 51.6; 93.16). CONCLUSION: The prophylactic use of the photopheresis allows to decrease the risk of infective complications after the kidney transplantation.