Challenges and considerations in diagnosing the kidney disease in deteriorating graft function

Prevention of Triglyceridemia by (Non-)Anticoagulant Heparin(oids) Does Not Preclude Transplant Vasculopathy and Glomerulosclerosis

Background: In renal transplantation, chronic transplant dysfunction (CTD) is associated with increased PCSK9 and dyslipidemia. PCSK9 is an enzyme that increases plasma cholesterol levels by downregulating LDLR expression. We recently showed increased PCSK9-syndecan-1 interaction in conditions of proteinuria and renal function loss. Treatment with heparin(oids) might be a therapeutic option to improve dyslipidemia and CTD. We investigated the effects of (non-)anticoagulant heparin(oids) on serum lipids, syndecan-1 and PCSK9 levels, and CTD development. Methods: Kidney allotransplantation was performed from female Dark Agouti to male Wistar Furth recipients. Transplanted rats received daily subcutaneous injections of saline, unfractionated heparin, and RO-heparin or NAc-heparin (2 mg heparin(oid)/kg BW) until sacrifice after 9 weeks of treatment. Results: Saline-treated recipients developed hypertension, proteinuria, and loss of creatinine clearance (all p < 0.05 compared to baseline), along with glomerulosclerosis and arterial neo-intima formation. Saline-treated recipients showed significant increase in plasma triglycerides (p < 0.05), borderline increase in non-HDLc/HDLc (p = 0.051), and ∼10-fold increase in serum syndecan-1 (p < 0.05), without significant increase in serum PCSK9 at 8 weeks compared to baseline. Heparin and non-anticoagulant RO-heparin administration in transplanted rats completely prevented an increase in triglycerides compared to saline-treated recipients at 8 weeks (both p < 0.05). Heparin(oids) treatment did not influence serum total cholesterol (TC), plasma syndecan-1 and PCSK9 levels, creatinine clearance, proteinuria, glomerulosclerosis, and arterial neo-intima formation, 8 weeks after transplantation. Combining all groups, increased syndecan-1 shedding was associated with TC (r = 0.5; p = 0.03) and glomerulosclerosis (r = 0.53; p = 0.021), whereas the non-HDLc/HDLc ratio was associated with the neo-intimal score in the transplanted kidneys (r = 0.65; p < 0.001). Conclusion: Prevention of triglyceridemia by (non-)anticoagulant heparin(oids) neither influenced PCSK9/syndecan-1 nor precluded CTD, which however did associate with the shedding of lipoprotein clearance receptor syndecan-1 and the unfavorable cholesterol profile.

Soluble CD30, Acute Rejection, and Graft Survival: Pre- and 6-Month Post-Transplant Determinations-When Is the Best Time to Measure?

BACKGROUND

Pretransplantation soluble CD30 (sCD30) has been shown to be a good predictor of acute rejection (AR) and graft loss. This study aimed to evaluate the effectiveness of sCD30 measured pretransplant and up to 6 months after transplantation as a predictor of AR, graft loss, and survival at 5 years post-transplantation. Subjects were patients receiving living donor renal transplants at Bonsucesso Federal Hospital (Rio de Janeiro) in 2006 and between August 2010 and May 2011.

METHODS

sCD30 was analyzed in samples collected pretransplantation and 7, 14, and 21, 28 days and 3, 4, 5, and 6 months post-transplantation from 73 kidney recipients.

RESULTS

Patients in the AR group did not present a positive correlation with the sCD30 levels pretransplant (P = .54); in the post-transplant period, the 7- to 14-day samples showed patients with AR had higher levels of this biomarker (P = .036). The graft survival in 5 years of follow-up was not different between groups.

CONCLUSIONS

The best time to predict AR using sCD30 is the 7- to 14-day sample; however, identifying and following the decrease of this biomarker from pre- to post-transplant seems to be better than just 1 measurement. The sCD30 post-transplant is another tool that may be used in monitoring patients after renal transplantation.

[Chronic kidney disease and kidney transplantation]

OBJECTIVES

To report epidemiology and characteristics of end-stage renal disease (ESRD) patients and renal transplant candidates, and to evaluate access to waiting list and results of renal transplantation.

MATERIAL AND METHODS

An exhaustive systematic review of the scientific literature was performed in the Medline database (http://www.ncbi.nlm.nih.gov) and Embase (http://www.embase.com) using different associations of the following keywords: "chronic kidney disease, epidemiology, kidney transplantation, cost, survival, graft, brain death, cardiac arrest, access, allocation". French legal documents have been reviewed using the government portal (http://www.legifrance.gouv.fr). Articles were selected according to methods, language of publication and relevance. The reference lists were used to identify additional historical studies of interest. Both prospective and retrospective series, in French and English, as well as review articles and recommendations were selected. In addition, French national transplant and health agencies (http://www.agence-biomedecine.fr and http://www.has-sante.fr) databases were screened using identical keywords. A total of 3234 articles, 6 official reports and 3 newspaper articles were identified; after careful selection 99 publications were eligible for our review.

RESULTS

The increasing prevalence of chronic kidney disease (CKD) leads to worsen organ shortage. Renal transplantation remains the best treatment option for ESRD, providing recipients with an increased survival and quality of life, at lower costs than other renal replacement therapies. The never-ending lengthening of the waiting list raises issues regarding treatment strategies and candidates' selection, and underlines the limits of organ sharing without additional source of kidneys available for transplantation.

CONCLUSION

Allocation policies aim to reduce medical or geographical disparities regarding enrollment on a waiting list or access to an allotransplant.

Differential Characteristics of Kidney Transplant Recipients According to 1-Year Chronic Kidney Disease Stage 3a and Stage 3b Graft Function

The outcomes of transplantation have improved, but more than 50% of kidney transplantation (KT) recipients are still reported to have renal function of chronic kidney disease (CKD) stage 3 at 1 year after KT. We reviewed all 1235 patients who received a KT in our institution between 2008 and 2012. Among these recipients, 77 and 289 cases were included in the estimated glomerular filtration rate (eGFR) at 1 year after KT 30-44 (CKD stage 3b) group and eGFR 45-59 (CKD stage 3a) group, respectively. Longer duration of dialysis (odds ratio [OR] = 1.007, 95% confidence interval [CI], 1.000-1.014, P = 0.047), older donors (OR = 1.064, 95% CI, 1.031-1.098, P < 0.001), delayed graft function (OR = 3.601, 95% CI, 1.031-1.098, P < 0.001), BK virus infection (OR = 2.567, 95% CI, 1.242-5.305, P = 0.011), and pneumonia (OR = 4.451, 95% CI, 1.388-14.279, P = 0.012) were contributing factors to eGFR 30-44 mL/min. Especially, ureteral stricture occurred more frequently in eGFR 30-44 group of deceased donor KT. However, acute rejection was not a significant risk factor of lower eGFR. Graft survival was better in the eGFR 45-59 group. However, this difference was smaller in deceased donor KT. Infections and urologic complications are also important contributing factors of lower graft function in CKD stage 3. In addition, dividing CKD stage 3 into subgroups might be more useful in living donor kidney transplantation.

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.

Evaluation of molecular profiles in calcineurin inhibitor toxicity post-kidney transplant: input to chronic allograft dysfunction

The molecular basis of calcineurin inhibitor toxicity (CNIT) in kidney transplantation (KT) and its contribution to chronic allograft dysfunction (CAD) with interstitial fibrosis (IF) and tubular atrophy (TA) were evaluated by: (1) identifying specific CNIT molecular pathways that associate with allograft injury (cross-sectional study) and (2) assessing the contribution of the identified CNIT signature in the progression to CAD with IF/TA (longitudinal study). Kidney biopsies from well-selected transplant recipients with histological diagnosis of CNIT (n = 14), acute rejection (n = 13) and CAD with IF/TA (n = 10) were evaluated. Normal allografts (n = 18) were used as controls. To test CNIT contribution to CAD progression, an independent set of biopsies (n = 122) from 61 KT patients collected at 3 and ~12 months post-KT (range = 9-18) were evaluated. Patients were classified based on 2-year post-KT graft function and histological findings as progressors (n = 30) or nonprogressors to CAD (n = 31). Molecular signatures characterizing CNIT samples were identified. Patients classified as progressors showed an overlap of 7% and 22% with the CNIT signature at 3 and at ~12 months post-KT, respectively, while the overlap was <1% and 1% in nonprogressor patients, showing CNIT at the molecular level as a nonimmunological factor involved in the progression to CAD.

Eculizumab in renal transplantation

Antibody-mediated rejection, be it acute, subacute or chronic, is currently recognized as the major cause of graft loss in kidney transplant recipients. Anti-HLA donor-specific antibodies are deleterious to the graft fate whether they pre-exist to the transplantation or appear in the course of transplantation. The role of complement is therefore prominent in most instances. As well, the role of complement activation is crucial in the recurrence of atypical hemolytic uremic syndrome post-transplantation (aHUS) as well as following ischemia-reperfusion injury leading to delayed graft function. Eculizumab, a fully humanized monoclonal antibody directed against the C5 component of the complement cascade is efficient in chronically and safely blocking complement activation for example in paroxysmal nocturnal hemoglobinuria. In the setting of kidney transplantation, there is convincing but still limited evidence that eculizumab is efficient in preventing both acute and chronic antibody-mediated rejection in highly sensitized recipients requiring desensitization before getting a living donor kidney transplant. Studies are currently ongoing to determine its efficacy and safety in ABO incompatible transplantation, in the prevention of acute and chronic rejection either with a living or a deceased donor kidney as well as in the prevention of delayed graft function. Similar to its efficacy in aHUS on native kidneys, eculizumab prevents or treats recurrence after kidney transplantation. There is still a lot of research to be performed in order to determine precisely the exact indications and the length of treatment with this very active but also very expensive drug that will undoubtedly revolutionize the current management of patients with donor specific antibodies (DSAs) and at risk of HUS recurrence.