Prevalence of Human Herpesvirus-8 and BK Polyoma Virus Infections in End-stage Renal Disease and the Influence of Renal Transplantation

Viral infections lead to significant morbidity and mortality in kidney transplant recipients. We evaluated 49 kidney transplant recipients for human herpesvirus 8 (HHV-8) and BK polyomavirus infections in conjunction with data obtained from 43 donors. The seroprevalence of HHV-8 was 6.9% in donors and 12.2% in recipients. HHV-8 DNA was detected below the limit of quantification (<5000 copies/mL) in a recipient with HHV-8 seropositivity at the pretransplant period and was undetectable at month 3 after transplantation. Transient viruria with BK polyomavirus was recorded in 10.2% of recipients without viremia. Multiple factors contribute to viral reactivation, particularly immunosuppressive treatment. Reduction in maintenance immunosuppression seems beneficial in terms of viral reactivation. At our center, routine use of valganciclovir for antiviral prophylaxis may be effective for the prevention of HHV-8 reactivation.

Corrected Panel-Reactive Antibody Positivity Rates for Hypersensitized Patients in Turkish Population With Calculated Panel-Reactive Antibody Software

INTRODUCTION

High rates of panel-reactive antibody (PRA) may decrease the chance of kidney transplantation and may result in long waiting periods before transplantation. The calculated PRA (cPRA) is performed based on unacceptable HLA antigens. These antigens are identified by a program that was created based on the antibodies that developed against the HLA antigens circulating in serum and on the risk of binding of these antibodies to antigens. The antigen profile of the population and antigen frequencies can be measured, and more realistic cPRA positivity rates may be obtained using this method.

MATERIALS AND METHODS

We developed a program based on the HLA antigens of 494 blood donors in 2 European Federation for Immunogenetics-accredited Tissue Typing Laboratories in Turkey. Next-generation sequencing-based tissue typing (HLA-A, -B, -C, -DR, -DQ, 4 digits) of the samples was performed. The PRA screening test was performed on 380 patients who were waiting for organ transplant from a cadaver in Istanbul Faculty of Medicine. The single antigen bead assay testing was performed to identify the antibody profiles on 48 hypersensitized patients.

RESULTS

The PRA testing results using the current methods were 44.6% ± 18.5%, and the cPRA rate was 86.2% ± 5.1%. The mean PRA positivity of the sensitized patients using the current methods was 44.6%; however, the rate was 86.2% using the cPRA.

DISCUSSION

cPRA shows the rate of the rejected donors according to all unacceptable antigens. The need for a list of unacceptable antigens in place of the PRA positivity rate is a real change in the sensitization-dependent calculation as cPRA positivity rate.

CONCLUSION

In principal, implementation of cPRA will encourage many centers and laboratories to adopt a standard measurement of sensitization in Turkey. It will increase the chances of better donor match, particularly for hypersensitized patients, by the creation of an unacceptable mismatch program using cPRA software.

Comparison of Two Different Inhalation Anesthetics on Grafted Kidney Function in Patients Undergoing Renal Transplantation Surgery: Desflurane or Sevoflurane?

BACKGROUND

Anesthetic management of patients during renal transplantation is vitally important for ensuring proper functioning of kidneys that have undergone ischemia-reperfusion damage. The goal of this prospective study was to compare the effects of 2 different inhalation agents (sevoflurane and desflurane) on grafted kidney function in renal transplantation surgery.

METHODS

Sixty-five patients who were scheduled for living donor renal transplantation were enrolled in the study. General anesthesia was performed on all patients. Thirty-five pairs of recipients and donors were anesthetized with sevoflurane (group S) and 30 pairs of recipients and donors were anesthetized with desflurane (group D). Each patient's demographic characteristics, immunologic and clinical data, and hemodynamic parameters were recorded. The estimated glomerular filtration rate was calculated in the preoperative period and on postoperative days 1 and 7. The blood samples were collected before the operation and on postoperative days 1 and 7 for measurement of serum creatinine, neutrophil gelatinase-associated lipocalin, and interleukin 18.

RESULTS

There were no significant differences in demographic characteristics or immunologic data between group D and group S. Intraoperative heart rate and mean arterial blood pressure were the same between groups. Creatinine, estimated glomerular filtration rate, neutrophil gelatinase-associated lipocalin, and interleukin 18 values did not differ between groups (P > .05) in the preoperative period and postoperative days 1 and 7.

CONCLUSIONS

Sevoflurane and desflurane had no adverse effects on grafted kidney functions according to short-term graft outcomes in patients undergoing living donor renal transplantation.

Re-evaluation of glomerulitis using occlusion criteria based on the Banff 2013 revision: a retrospective study

The presence of occlusion/near-occlusion of glomerular capillaries was recently added to the existing definition of glomerulitis (g). We retrospectively re-evaluated 135 renal allograft biopsies regarding g to ensure no antibody-damaged grafts were missed. Previous and revised g scores (pg and rg, respectively) were compared for clinicopathologic correlations. The g score did not change in 100 (74.1%) biopsies. Thirty-five (25.9%) biopsies were changed to a lower score. Sensitivity and specificity of pg and rg for the presence of donor-specific antibodies (DSA) were 76% vs. 58% and 70% vs. 79%, respectively. Pg score indicated graft loss with 65% sensitivity and 63% specificity, whereas rg showed 46% sensitivity and 71% specificity. Area under the curve (AUC) values in ROC analysis for DSA and graft loss were as follows: pg, 0.773; rg, 0.693; and pg, 0.635; rg, 0.577, respectively. A comparison of the two AUC values revealed a significant difference between pg and rg only for DSA (P = 0.0076). Pg and post-transplant time of biopsy independently predicted graft loss, whereas rg did not. In conclusion, revised g scores showed lesser sensitivity but higher specificity for DSA and graft loss. Recent definition of g missed antibody-mediated rejection in few cases, and it was not an independent predictor for graft loss.

Pregnant Woman with Atypical Hemolytic Uremic Syndrome Delivered a Healthy Newborn under Eculizumab Treatment

Pregnancy-associated thrombotic microangiopathy is a very rare condition; however, it significantly increases fetal or maternal morbidity and mortality. Pregnancy may trigger atypical hemolytic uremic syndrome (aHUS) or thrombotic thrombocytopenic purpura. The risk for pregnancy-associated aHUS is highest during the second pregnancy. The outcome is usually poor with 50–60% mortality; renal dysfunction and hypertension are the rule in those who survive the acute episode. After the development of complement regulation mechanisms and aHUS pathogenesis, eculizumab has been widely used as a first-line treatment in aHUS. Eculizumab has been produced to minimize immunogenicity and Fc-mediated functions, including recruitment of inflammatory cells and complement activation, and using eculizumab in first-line treatment improves kidney function. Recent studies showed that early diagnosis and rapid use of eculizumab in first-line treatment improve outcomes. We demonstrate a case with pregnancy-triggered aHUS occurring in the second trimester, who was successfully treated and delivered a healthy baby under eculizumab treatment.

Serum Osteoprotegerin Levels Related With Cardiovascular Risk Factors in Chronic Kidney Disease

BACKGROUND

To evaluate osteoprotegerin (OPG) levels in relation to cardiovascular (CV) risk factors in patients with chronic kidney disease (CKD) on different regimens of renal replacement therapy.

METHODS

A total of 143 patients with CKD and 30 healthy controls were included in this study and divided into five categories, including predialysis patients with chronic renal failure (preD; n = 36), chronic peritoneal dialysis patients (PD; n = 36), hemodialysis patients (HD; n = 35), renal transplant patients (RT; n = 36), and controls (n = 30). Data on demographics, concomitant diseases and CV risk factors, serum OPG levels, and correlates of serum OPG levels were determined.

RESULTS

Serum OPG (pmol/l) levels were significantly higher in HD (P <0.001 for each), PD (P <0.001 for each), and preD (P <0.01 vs. control, P <0.05 vs. RT) groups than RT and control groups. Diabetics than nondiabetics in HD (P = 0.008), PD (P = 0.024), and RT (P = 0.004) groups and males than females in PD group (P = 0.021) had higher OPG levels. Serum OPG levels were associated positively with age in HD (P <0.001), PD (P = 0.001), and in overall population (P <0.001).

CONCLUSION

Our findings revealed increased serum levels of OPG in dialysis and preD patients compared to RT and controls. In the patient groups receiving two dialysis treatment, the levels were worse, indicating a more pronounced vascular injury. Age, C-reactive protein (CRP), high-density lipoprotein cholesterol (HDL-C), and cystatin C (CysC) in CKD patients, CRP and PTH in the control subjects, and age and BMI in the overall population were the significant correlates of serum OPG levels.

The effect of histopathologic and clinical features on allograft survival in renal transplant patients with antibody-mediated rejection

Background: Antibody-mediated rejection is a frequent cause of graft failure; however, prognostic indications of this complication have not been well defined. The aim of this study was to evaluate the association of histopathological and clinical features and to determine the effect of these findings on allograft survival in patients with AMR.

Methods: Fifty-two patients suffered from AMR (30 male; mean age 39 ± 11 years) were included in the study. Data were investigated retrospectively and graft survival was analyzed. All transplant biopsies were evaluated according to Banff 2009 classification.

Results: Of the 52 cases, 45 were transplanted from living-donors. Twenty-one patients were diagnosed in the first 3-months after transplantation. Graft survival was 65% at 12 months and 54% at 36 months. Mean serum creatinine at time of biopsy was 3.8 ± 3.6 mg/dL. Thirty-five of the 52 cases showed diffuse C4d positivity, 12 cases showed focal and 5 remained C4d negative. One of the patients died, 13 experienced graft loss and 38 survived with functioning grafts. Serum creatinine levels at time of biopsy were correlated with graft survival (p = .021: OR = 1.10: 95 % CI = 1.015–1.199). In terms of the impact of pathological findings; tubulitis (p=.007: OR = 2.62: 95 % CI = 1.301–5.276), intimal arteritis (p=.017: OR = 2.85: 95% CI = 1.205–6.744) and interstitial infiltration (p=.004: OR = 3.37: 95% CI = 1.465–7.752) were associated with graft survival.

Conclusions: Serum creatinine at time of biopsy, tubulitis, intimal arteritis and interstitial infiltration were significantly associated with graft survival. Antibody-mediated rejection is associated with reduced long-term graft survival.

A simulator for perfusion training

In this study, a patient simulator was designed and fabricated to train students to respond to various clinical situations associated with heart-lung bypass machine operation and to respond to changes in patient clinical parameters. The students will use the simulator to gain pre-clinical experience. The training system will initially simulate normal heart-lung bypass conditions. During a training session, the instructor will be able to simulate problems that may happen during a real procedure. Some of these problems are stopping of rotation of one of the roller pump heads, abnormal changes in the vital parameters, such as oxygenation level or biochemical values, high blood pressure, and occlusion in arterial or venous lines. The simulator will train students to respond properly to these situations, hence, allowing them to gain clinical experience without impacting patient safety and the outcome of real life procedures. The simulator can also be used for assessment of the students’ competency levels.

Effect of Donor Nephrectomy Technique on Recipient Lymphatic Drainage

AIM

We sought to evaluate the postoperative recipient lymphatic drainage depending on open donor nephrectomy (ODN) or laparoscopic (LDN) techniques.

METHOD

Between March 2012 and August 2014, 58 patients underwent renal transplantation from living-related donors. Thirty donors underwent ODN (group 1), and 28 LDN (group 2). Operations were performed by the same surgeons. Both cranial and caudal drainage catheters for lymphatic leakage were placed preoperatively and all the recipients received tacrolimus, mycophenolate mofetil, and steroid as immunosuppressive regimen. None of the patients had coagulation abnormalities.

RESULTS

All grafts were functioning during the early postoperative period and diuresis was ensured. No difference was observed on early postoperative period regarding to acute rejection (P = .329) or infection (P = .546). No difference was seen concerning mycophenolate mofetil and mycophenolate sodium regimens among the 2 groups (P = .227). In groups 1 and 2, the cranial drainage catheters were not taken out until postoperative days 5.5 ± 2.5 (range, 0-11) and 6.4 ± 3.8 (range, 0-14) and the caudal catheters stayed in place until days 8.8 ± 3.5 (range, 1-16) and 9.9 ± 5.9 (range, 3-22), respectively. No difference was found when comparing the cranial (P = .308) and caudal (P = .426) drainage periods. However, during clinical acute rejection episodes the cranial drainage period was longer in group 1 (P = .003). Three patients developed lymphoceles, 1 requiring drainage, in group 2.

CONCLUSIONS

There seems to be no difference in recipient lymphatic drainage by donor nephrectomy technique. A laparoscopic procedure may be advantageous owing to shorter lymphatic drainage during clinical acute rejection episodes.

Genetic association of interleukin-2, interleukin-4, interleukin-6, transforming growth factor-β, tumour necrosis factor-α and blood concentrations of calcineurin inhibitors in Turkish renal transplant patients

Cytokines are essential for the control of the immune response as most of the immunosuppressive drugs target cytokine production or their action. The calcineurin inhibitors (CNIs) cyclosporine (CsA) and tacrolimus are immunosuppressive drugs widely used after renal transplantation to prevent allograft rejection. They are characterized by large interindividual variability in their pharmacokinetics; therefore, monitoring their blood concentrations is important to predict their optimal dosage following transplantation. Calcineurin inhibitors inhibit the phosphatase activity of calcineurin, thereby suppressing the production of other cytokines such as transforming growth factor (TGF-β), tumour necrosis factor-α (TNF-α), interleukin (IL)-6, IL-2, and IL-4. The aim of this study was to investigate the relationship between polymorphisms of cytokines and blood concentrations of CNIs in renal transplant patients. The study included 53 CsA-treated renal transplant patients and 37 tacrolimus-treated renal transplant patients. Cytokine polymorphisms were analysed using polymerase chain reaction (PCR) sequence-specific primers with the cytokine CTS-PCR-sequence-specific primers Tray Kit; University of Heidelberg. Blood concentrations of CNIs were determined with Cloned Enzyme Donor Immunoassay (CEDIA) method. Patients with TC genotype of TGF-β at codon 10 had lower CsA blood concentrations than the TT and CC genotypes (P = 0.005) at 1 month in CsA treatment group. The ratio of blood concentration/dose of CsA for patients with TGF-β1-codon 10 TC genotype was lower than for patients with TT, CC genotypes, and the dose given to these patients was higher in the first month (P = 0.046). The ratio of blood concentration/dose of CsA for patients with IL-2-330 GG genotype was higher than for patients with GT, TT genotypes, and the dose given to these patients was lower at first month and sixth months (P = 0.043, P = 0.035 respectively). The tacrolimus blood concentrations were significantly higher in patients with the genotype GG of IL-2-330 (P = 0.012) at the third month. Patients who had the TC genotype TGF-β codon 10 had lower CsA blood concentrations and this group had higher acute rejection (P = 0.033). These results suggest that the genotyping for TGF-β-codon 10, IL-2-330 and IL-6-174 polymorphisms may help individualized immunosuppressive dosage regiments.

Renal transplantation in a patient with chronic granulomatous disease: case report

Chronic granulomatous disease (CGD) is a genetic disease caused by structural mutations in the enzyme NADPH oxidase that results in severe immunodeficiency. End-stage renal disease occurs in this patient population and is attributed to various factors, including infections, amyloidosis, and nephrotoxic anti-infective agents. In this report, we present our experience in transplantation for a patient with CGD complicated by isolated hepatic tuberculosis abscess. The course of the case demonstrates the absolute requirements for a multidisciplinary and compulsive approach before, during, and after transplantation. This case report also highlights the unexpectedly benign effects of immunosuppressive therapy in this patient population.

Pentraxin 3 and C-reactive protein as inflammatory markers after a kidney transplant

OBJECTIVES

There are numerous changes in inflammatory status that occur after a kidney transplant. Pentraxin 3 is a marker of inflammation, but little information is available about pentraxin 3 levels after a kidney transplant. We evaluated the relation between pentraxin 3 and other inflammatory markers including high sensitivity C-reactive protein, interleukin 6, and tumor necrosis factor alpha in kidney transplant recipients.

MATERIALS AND METHODS

Adult patients (40 patients; aged, 18-80 y; mean age, 38 ± 10 y) who had a kidney transplant from living-related donors were studied. Patients who had comorbidities associated with chronic inflammation were excluded. Blood samples were obtained before starting immunosuppressive treatment and 2 months after kidney transplant for measurement of pentraxin 3, high sensitivity C-reactive protein, interleukin 6, and tumor necrosis factor α levels.

RESULTS

After transplant, mean levels of high sensitivity C-reactive protein and interleukin 6 decreased but levels of pentraxin 3 and tumor necrosis factor alpha did not change. There were significant correlations between interleukin 6 and high sensitivity C-reactive protein before transplant (r = 0.71; P ≤ .0001) and after transplant (r = 0.45; P ≤ .003). There was no correlation between tumor necrosis factor alpha and high sensitivity C-reactive protein before transplant, but there was a significant correlation between tumor necrosis factor alpha and high sensitivity C-reactive protein after transplant (r = 0.36; P ≤ .03). There was no correlation between interleukin 6 and pentraxin 3, tumor necrosis factor alpha and pentraxin 3, or high sensitivity C-reactive protein and pentraxin 3 before or after transplant.

CONCLUSIONS

After a kidney transplant, pentraxin 3 may not be useful in determining inflammatory status, and high sensitivity C-reactive protein may be better than pentraxin 3 as a marker of inflammation.

Effect of MDR1 polymorphisms on the blood concentrations of tacrolimus in Turkish renal transplant patients

BACKGROUND

Tacrolimus, a calcineurin inhibitör, is prescribed to prevent allograft rejection in renal transplantation. Tacrolimus not only has a narrow therapeutic index, but also shows significant interindividual differences. The absorption and metabolism of this drug are affected by multidrug resistance (MDR) 1 gene polymorphisms that correlated with single-nucleotide polymorphisms (SNPs) affecting in vivo P-glycoprotein activity. This study investigated associations of MDR1 gene C3435T polymorphism with tacrolimus blood concentrations and dose requirements as well as acute rejection episodes among Turkish renal transplant patients.

METHODS

One hundred living-donor transplant recipients and 150 healthy control subjects underwent C3435T genotyping using polymerase chain reaction-restriction fragment length polymorphism. Blood concentrations of tacrolimus were determined with the cloned enzyme donor immunoassay.

RESULTS

The CC, CT, and TT genotype frequencies among patients were, respectively, 44.0%, 33.0%, and 23.0% versus 36.7%, 43.3%, and 20.0% among control subjects. There was no significant difference between (P = .061; P = .102; P = .211; respectively). The ratio of blood concentration to dose of tacrolimus for patients with mutant homozygous 3435 TT genotype was higher than that of wild-type 3435 CC genotype homozygous individuals. The doses for these patients were lower at 1, 3, and 12 months (P = .048; P = .03; P = .041, respectively). There were no significant differences between the groups regarding coprescription of drugs that affect tacrolimus concentrations, such as diltiazem. Acute rejection episodes were not associated with the CC vs CT or TT genotypes: odds ratio (OR), 0.517 (95% confidence interval [CI], 0.190-1.407; P = .192); OR 1.558 (95% CI, 0.587-4.136; P = .372); OR 1.346; (95% CI, 0.456-3.968; P = .590), respectively.

CONCLUSIONS

Determination of MDR1 polymorphism may help to achieve target of tacrolimus blood concentrations.

Eculizumab for salvage treatment of refractory antibody-mediated rejection in kidney transplant patients: case reports

Antibody-mediated rejection (AMR) in a group of preoperatively desensitized patients may follow a dreadful course and result in loss of the transplanted kidney. In several cases, conventional therapies including plasmapheresis, intravenous immunoglobulin, and anti-CD 20 therapy can resolve AMR successfully. But in some cases the load of immunoglobulins that can activate complement cascade may submerge the routine desensitization therapy and result in the formation of membrane attack complexes. Eculizumab, monoclonal antibody against C5, was reported to be an option in cases with severe AMR that are resistant to conventional therapy. Here, we present two cases of acute-onset AMR in preoperatively desensitized patients. Eculizumab was used as a salvage agent in addition to conventional therapy. Given the bad prognosis for renal transplants displaying acute injury progressing rapidly to cortical necrosis on the biopsy, the prompt use of eculizumab could have the advantage of immediate effects by stopping cellular injury. This can provide a therapeutic window to allow conventional treatment modalities to be effective and prevent early graft loss.