Single-centre experience with the treatment of high-prevalence metabolic syndrome in kidney transplant patients in Bosnia and Herzegovina

Aim To analyse prevalence of metabolic syndrome (MS) in kidney transplant recipients at the University Clinical Centre Tuzla in Bosnia and Herzegovina (B&H), and determine effects of a modern drug therapy in achieving target metabolic control in kidney transplant patients. Methods A single-centre prospective study that included 142 kidney transplant patients over one year follow-up period was conducted. Patient data were collected during post-transplant periodical controls every 3 months including data from medical records, clinical examinations and laboratory analyses. Results Out of 142 kidney transplant patients, MS was verified in 85 (59.86%); after a pharmacologic treatment MS frequency was decreased to 75 (52.81%). After a one-year period during which patients were receiving therapy for MS, a decrease in the number of patients with hyperlipoproteinemia, decrease in average body mass index (BMI), glycemia and haemoglobin A1C (HbA1C) were observed. Hypertension did not improve during this period, which can be explained by transplant risk factors in the form of immunosuppressive drugs and chronic graft dysfunction. Conclusion A significant reduction in components of the metabolic syndrome after only one year of treatment was recorded, which should be the standard care of kidney transplant patients.

The Effect of the Gut Microbiota on Transplanted Kidney Function

The intestinal microflora is extremely important, not only in the processes of absorption, digestion and biosynthesis of vitamins, but also in shaping the immune and cognitive functions of the human body. Several studies demonstrate a correlation between microbiota composition and such events as graft rejection, kidney interstitial fibrosis, urinary tract infections, and diarrhoea or graft tolerance. Some of those changes might be directly linked with pathologies such as colonization with pathogenic bacterial strains. Gut microbiota composition also plays an important role in metabolic complications and viral infections after transplantation. From the other side, gut microbiota might induce graft tolerance by promotion of T and B regulatory cells. Graft tolerance induction is still an extremely important issue regarding transplantology and might allow the reduction or even avoidance of immunosuppressive treatment. Although there is a rising evidence of the pivotal role of gut microbiota in aspects of kidney transplantation there is still a lack of knowledge on the direct mechanisms of microbiota action. Furthermore, some of those negative effects could be reversed by probiotics of faecal microbiota trapoinsplantation. While diabetes and hypertension as well as BKV and CMV viremia are common and important complications of transplantation, both worsening the graft function and causing systemic injuries, it opens up potential clinical treatment options. As has been also suggested in the current review, some bacterial subsets exhibit protective properties. However, currently, there is a lack of evidence on pro- and prebiotic supplementation in kidney transplant patients. In the current review, we describe the effect of the microbiota on the transplanted kidney in renal transplant recipients.

Analysis of Cadmium, Mercury, and Lead Concentrations in Erythrocytes of Renal Transplant Recipients from Northwestern Poland

Simple Summary

The aim of this study is to determine the blood erythrocyte concentrations of toxic metals (Cd, Pb, and Hg) in renal transplant recipients. Additionally, we analyzed the effect of selected biological and environmental factors, including the intake of various immunosuppressive drug regimens and smoking, on these xenobiotic concentrations. In summary, our data suggest that, smoking is associated with Pb and Cd concentrations, and gender, age change depending on Pb concentration in erythrocytes of renal transplant recipients. Additionally, this is the first research that suggests that immunosuppressive regimen, depending on type of immunosuppressive drugs combination affects Pb concentration in erythrocytes of the mentioned group of patients. It seems to be crucial information for patients who use immunosuppressive drugs.

Abstract

Cadmium (Cd), mercury (Hg), and lead (Pb) exhibit highly nephrotoxic properties, and their high concentrations can lead to renal failure. Much research has been conducted on the concentrations of heavy metals, microelements, and macroelements in the blood, but little is known about the concentration of Cd, Pb, and Hg in erythrocytes of renal recipients. The aim of this study is to determine the blood erythrocyte concentrations of toxic metals (Cd, Pb, and Hg) in renal transplant recipients (RTRs). Additionally, we analyzed the effect of selected biological and environmental factors, including the intake of various immunosuppressive drug regimens and smoking, on these xenobiotic concentrations. The material consisted of erythrocyte samples from 115 patients of the Department of Nephrology, Transplantology, and Internal Medicine at Independent Public Clinical Hospital No. 2, Pomeranian Medical University, Szczecin, in northwestern Poland. Cd, Hg, and Pb levels in the erythrocytes were quantified by inductively coupled mass spectroscopy (ICP-MS). Equal concentrations of Cd were found in erythrocytes of both female and male transplant recipients. The highest level of Hg was seen in women, and women overall had statistically higher concentrations of Pb than men. Comparison of metal concentrations between those over 50 years and those under it showed that Pb concentration was also significantly higher in renal transplant recipients over 50. Pb concentration was almost twice as high in RTRs who used tacrolimus with mycophenolate mofetil than in RTRs who used cyclosporine A with mycophenolate mofetil. The highest level of Cd was seen in smokers, who had 3.25 µg/L. This value was significantly higher than in ex-smokers (p = 0.001) and with RTRs who had never smoked. There were significantly higher levels of Pb in the erythrocytes of RTRs who were ex-smokers than in those who had never smoked. A statistically significant correlation was found between Cd and Pb concentrations. Additionally, we have noticed significant positive correlation between Pb and age (R = 0.37), gender (R = 0.24) and significant negative correlation of Pb with GFR (R = −0.33). We have also found significant positive correlation between Hg and age (R = 0.21). In summary, our data suggest that, smoking is associated with Pb and Cd concentrations, and gender, age change depending on Pb concentration in erythrocytes of RTRs. Additionally, this is the first research that suggests that immunosuppressive regimen, depending on type of immunosuppressive drugs combination affects Pb concentration in erythrocytes of RTRs. It seems to be crucial information for patients who use immunosuppressive drugs.

Eplet incompatibility in pediatric renal transplantation

Eplet incompatibility appears to be a better predictor of the de novo appearance of DSA post-Tx than HLA antigen matching in adults. We evaluated the HLA Matchmaker® software (version 2.1) in our pediatric cohort to predict the appearance of DSA post-Tx. We included 70 pediatric patients (26 girls, 10 living donors, mean age 11.2 ± 3.9 years) after a first R-Tx (January 2010-August 2016), without prior immunization, having complete HLA typing (A, B, C, DRB1 and DQB1) and DSA follow-up for at least one year. The mean of HLA and eplet incompatibilities was 4.7 ± 1.3 and 15.5 ± 6.1, respectively, with a correlation coefficient r² between these two variables of 0.34 (P < .001). The eplet load was 12.8 ± 5.0 in living donors vs 15.9 ± 6.2 in deceased donors (P = NS), 12.6 ± 6.1 in preemptive R-Tx (n = 14) vs 16.3 ± 5.9 for non-preemptive R-Tx (P = .04). Seven patients (10%) developed DSA during the 3.5 ± 1.2 years post-Tx. The eplet load was 13.7 ± 5.5 for those who developed DSA vs 15.7 ± 6.1 for the others (P = NS). In our single-center series of pediatric R-Tx with good HLA matching and lower eplet load than previously published series, eplet incompatibilities do not predict the development of DSA. The question of the HLA matching requirement and the daily interest of the HLA Matchmaker® software to help select the grafts remain open.

Screening for Transplant Renal Artery Stenosis: Ultrasound-Based Stenosis Probability Stratification

OBJECTIVE

The objective of our study was to evaluate which spectral Doppler ultrasound parameters are useful in patients with clinical concern for transplant renal artery stenosis (TRAS) and create mathematically derived prediction models that are based on these parameters.

MATERIALS AND METHODS

The study subjects included 120 patients with clinical signs of renal dysfunction who had undergone ultrasound followed by angiography (either digital subtraction angiography or MR angiography) between January 2005 and December 2015. Five ultrasound variables were evaluated: ratio of highest renal artery velocity to iliac artery velocity, highest renal artery velocity, spectral broadening, resistive indexes, and acceleration time. Angiographic studies were categorized as either showing no stenosis or showing stenosis. Reviewers assessed the ultrasound examinations for TRAS using all five variables, which we refer to as the full model, and using a reduced number of variables, which we refer to as the reduced-variable model; sensitivities and specificities were generated.

RESULTS

Ninety-seven patients had stenosis and 23 had no stenosis. The full model had a sensitivity and specificity of 97% and 91%, respectively. The reduced-variable model excluded the ratio and resistive index variables without affecting sensitivity and specificity. We applied cutoff values to the variables in the reduced-variable model, which we refer to as the simple model. Using these cutoff values, the simple model showed a sensitivity and specificity of 96% and 83%. The simple model was able to categorize patients into four risk categories for TRAS: low, intermediate, high, and very high risk.

CONCLUSION

We propose a simple model that is based on highest renal artery velocity, distal spectral broadening, and acceleration time to classify patients into risk categories for TRAS.

Evidence of hepatitis E virus transmission by renal graft

Hepatitis E virus (HEV) can cause chronic infection among immunocompromised patients, especially solid organ transplant recipients, and can evolve to cirrhosis. Several modes of transmission are known. Here we describe the first two cases, to our knowledge, of HEV infection transmitted by a kidney graft from the same infected donor that led to chronic hepatitis. Consequently, systematic screening of donors by HEV serology and HEV RNA detection by polymerase chain reaction, particularly in endemic regions, should be considered.

Endoureteral Management of Renal Graft Ureteral Stenosis by the Use of Long-Term Metal Stent: An Appealing Treatment Option

Background: Ureteral stenosis is part of the common complications of renal graft reported in 3% to 7% of cases. Multiple treatments have been introduced regarding length and position of the stenosis. Metal stents for urologic purpose were created in 1998. Double percutaneous antegrade and transurethral retrograde access to a ureteral stenosis to a long-term metal stent procedure has been rarely described. Case Presentation: Here, we present a case of a ureteral stricture in a double ipsilateral kidney graft with a common ureter. A 67-year-old patient presented with obstructive nephritis associated with acute renal failure 6 years after a double renal graft with a uretero-ureteral end-to-side anastomosis. Abdominal CT scan showed double pelvic dilation. The patient underwent double percutaneous nephrostomies and antegrade pyelogram showed both renal pelvic and ureter dilations caused by a severe chronic ureteral stenosis at junction into the bladder. A Double-J ureteric stent was then inserted retrogradely over a guidewire as first-line treatment. Due to recurrent urinary tract infections (UTIs), removal and replacement of Double-J stents were carried out by placing a thermoexpandable metal stent Memokath^® 051 (Bard, Pnn Medical) through the common ureter by a double antegrade and retrograde approach. Treatment was effective with a good renal function maintained after a 3-year follow-up without UTIs. Conclusion: Double antegrade and retrograde access to a long-term metal stent treatment can be seen as an alternative treatment to either endoscopy or open surgery. Further studies should be continued using larger series.

The value of Doppler ultrasound in predicting delayed graft function occurrence after kidney transplantation

The aim of this study was to assess the predictive value of blood flow velocity and vascular resistance measured by Doppler ultrasound in terms of pulsatility index (PI) and resistive index (RI) respectively, in the occurrence of delayed graft function (DGF) after kidney transplantation. This prospective study enrolled kidney transplant recipients operated from January 2005 to April 2009 in the 1st Department of General, Oncological and Gastroenterological Surgery, Jagiellonian University Medical College, Kraków, Poland. The medical records of 53 kidney transplant recipients from deceased donors were reviewed. PI and RI values of the graft arcuate artery were calculated immediately after blood flow restoration and on the 1st, 2nd, 4th and 8th post-operative day. DGF was observed in 20 patients (37.7%), while 33 patients (62.3%) had immediate restoration of the kidney function. The mean intraoperative values of RI and PI from patients with DGF were significantly higher in comparison to patients without DGF (0.9 vs. 0.74, p <0.001; 1.76 vs. 1.54, p = 0.019, respectively). Post-operatively, the RI and PI values remained stable and significantly higher in DGF group. The highest sensitivity of RI to predict DGF occurrence was observed intraoperatively and on the first postoperative day, with values of 77.8% and 72.2%, respectively. The risk of DGF occurrence with intraoperative RI value ≥0.9 increased by 13-fold, and with intraoperative PI value ≥1.9 by 12-fold. This increase was even more prominent during the first post-operative day with RI value ≥0.9 or PI value ≥1.9 with 19-fold increase in the risk of DGF occurrence. According to our study, the utilization of Doppler ultrasound with measurement of hemodynamic parameters (PI, RI), play a crucial role in predicting the outcomes of kidney transplantation.

Quantitative (99m)Tc DTPA renal transplant scintigraphic parameters: assessment of interobserver agreement and correlation with graft pathologies

Various (99m)Tc DTPA scintigraphic quantitative parameters for renal graft function assessment have been recommended, but none is universally accepted. In this study, 439 dynamic renal transplant scintigraphies (DRTS) were retrospectively analysed. In the first set of studies, four observers analysed the 47 random DRTS and interobserver agreement of eleven derived parameters was assessed. In the other set of studies, 181 instances of DRTS, performed on 127 recipients with renal biopsies within five days of each other were selected for correlation with pathology. Hilson's Perfusion index (HI), ΔP, P:Pl, P:U & T10 were selected for this analysis. The pathologies were categorized into renal vascular compromise (RVC; n = 20), acute tubular necrosis (ATN; n = 40), vascular rejection (VR; n = 34), interstitial rejection (IR; n = 33), normal (NOR; n = 36) and unclassified pathologies (n = 18). A majority of the parameters showed good Intraclass correlation (ICC). HI differentiated well between grafts with RVC and the remainder of the study cohort, (p < 0.0001; AUC = 0.84); at a cut-off > 278, it had 84% sensitivity and 78% specificity (Likelihood ratio = 3.8). At < 278, it had 98% 'negative' predictive value for RVC. HI also showed reasonable association with VR (p = 0.02; AUC = 0.62) and IR (p = 0.009; AUC = 0.65). However, significant overlap of HI values between various subgroups was noted. Other parameters had good ICC but were not effective in differentiating graft pathologies. Of the measured parameters, only HI proved to be useful for the pathological assessment, particularly in the identification of vascular compromise. This parameter, however, has lower specificity in differentiating the other pathologies.