A Simple Novel Technique to Estimate Tacrolimus Dosages During the Early Post Kidney Transplantation Period.

BACKGROUND: Tacrolimus pharmacokinetics prediction by CYP3A5 genotyping is not available in many Asian resource-limited settings. Therefore, an alternative technique is needed to estimate the dose of tacrolimus perioperatively. The 12-hour level after the first dose (C12-0) is an alternative technique for estimating the dose of tacrolimus. This simple and inexpensive calculation technique can be used by any transplantation center. METHODS: A prospective study on a cohort of 57 incident post-kidney transplant recipients was conducted. The whole-blood tacrolimus trough level (C12-0) was measured at 12 hours after the first dose (0.1 mg/kg) of orally administered tacrolimus during transplantation. Concomitant medications with CYP3A5 inhibitors/inducers were not allowed. Genotyping for CYP3A5 expression was carried out by reverse transcription polymerase chain reaction. The dosages and trough levels of tacrolimus at postoperative day 7 and postoperative months 1 to 3 were measured and analyzed for the dose requirements for therapeutic levels (mg/kg/d). RESULTS: The doses of tacrolimus were widely diverse, ranging from 0.049 to 0.260 mg/kg/d and 0.031 to 0.298 mg/kg/d at day 7 and months 1 to 3, respectively. There were 9, 28, and 20 patients (15.8%, 49.1%, and 35.1%) with CYP3A5 *1/*1, *1/*3, and *3/*3, respectively. The CYP3A5 genotypes were significantly correlated with the target tacrolimus dose at day 7 (r(2) = 0.307) and the stable dose at months 1 to 3 (r(2) = 0.337). The C12-0 level also was significantly correlated with the dose of tacrolimus at day 7 (r(2) = 0.546) and the stable dose at months 1 to 3 (r(2) = 0.406). CONCLUSIONS: There were strong correlations between the C12-0 level and the tacrolimus doses during the perioperative period at day 7 and the stable period at 1 to 3 months. Countries with limited resources for genotype testing can use the C12-0 level as an alternative to estimate the tacrolimus dose.

Risk Factors of Cytomegalovirus Disease in Kidney Transplant Recipients: A Single-Center Study in Thailand.

BACKGROUND: Cytomegalovirus (CMV) infection significantly causes morbidity in kidney transplant (KT) recipients. This study aims to investigate the incidence, timing, and risk factors of CMV infection in KT recipients. METHODS: This is a single-center retrospective study at a tertiary referral hospital. Patients who underwent KT from January 2012 to September 2014 were included. CMV infection was defined as the presence of CMV measured by polymerase chain reaction. Logistic regression analysis was performed to assess independent risk factors of CMV infection after KT. RESULTS: Of 121 KT patients enrolled, 120 patients had CMV D(+)/R(+) serostatus, and 1 had D-/R(+). CMV infection occurred in 33 (27.2%) of patients with a median follow-up time of 16 (IQR 4-25) months. Of those, 25 had CMV viremia and 8 had CMV disease mainly involving the gastrointestinal system. In total, 86% of CMV cases occurred within 3 months. All recipients received anti-IL-2 receptor antibody (IL-2 RA), low-dose rabbit antithymocyte globulin (rATG; total of 1.5 mg/kg), or standard-dose rATG (1.5 mg/kg/day for 3-5 days) for induction. Of those, the incidences of CMV infection were 19.6%, 50%, and 67%, respectively. Preemptive strategy was used in all but 1 patient in the IL-2 RA and low-dose rATG group, whereas universal prophylaxis was given in 67% of patients in the standard-dose rATG group. Independent risk factors of CMV infection were older recipient age (per 10-year increase, OR 1.5; 95% CI 1.04-2.23), and induction with standard (OR 8.19; 95% CI 2.29-34) and low-dose rATG (OR 3.87; 95% CI 1.06-12.23). CONCLUSIONS: More than 25% of KT recipients developed CMV infection within 6 months after KT. The risk is increased in older recipients and induction with rATG. The level of CMV risk in low-dose rATG is 52% lower than in standard-dose rATG. In a limited-resource setting such as Thailand, deferred or preemptive strategy may be acceptable in patients who received IL-2 RA and low-dose rATG, while prophylactic therapy should be given to patients who received standard-dose rATG.

The outcomes of kidney transplantation in hepatitis B surface antigen (HBsAg)-negative recipients receiving graft from HBsAg-positive donors: a retrospective, propensity score-matched study.

The outcomes of kidney transplantation (KT) from hepatitis B surface antigen-positive [HBsAg(+)] donors to HBsAg(-) recipients remain inconclusive, possibly due to substantial differences in methodological and statistical models, number of patients, follow-up duration, hepatitis B virus (HBV) prophylactic regimens and hepatitis B surface antibody (anti-HBs) levels. The present retrospective, longitudinal study (clinicaltrial.gov NCT02044588) using propensity score matching technique was conducted to compare outcomes of KT between HBsAg(-) recipients with anti-HBs titer above 100 mIU/mL undergoing KT from HBsAg(+) donors (n = 43) and HBsAg(-) donors (n = 86). During the median follow-up duration of 58.2 months (range 16.7-158.3 months), there were no significant differences in graft and patient survivals. No HBV-infective markers, including HBsAg, hepatitis B core antibody, hepatitis B extracellular antigen and HBV DNA quantitative test were detected in HBsAg(+) donor group. Renal pathology outcomes revealed comparable incidences of kidney allograft rejection while there were no incidences of HBV-associated glomerulonephritis and viral antigen staining. Recipients undergoing KT from HBsAg(+) donors with no HBV prophylaxis (n = 20) provided comparable outcomes with those treated with lamivudine alone (n = 21) or lamivudine in combination with HBV immunoglobulin (n = 2). In conclusion, KT without HBV prophylaxis from HBsAg(+) donors without hepatitis B viremia to HBsAg(-) recipients with anti-HBs titer above 100 mIU/mL provides excellent graft and patient survivals without evidence of HBV transmission.

Effects of atorvastatin on the pharmacokinetics of everolimus among kidney transplant recipients.

BACKGROUND: Hyperlipidemia occurs in up to 50% of kidney transplant (KT) recipients who take everolimus (EVL). As a result of this, statins are the most commonly prescribed lipid-lowering drugs among these patients. However, we are concerned whether there are any drug interactions between EVL and statins, because both of these drugs use the same pharmacokinetics pathway. Therefore, we assessed the effects of concomitant use of EVL and atorvastatin. METHODS: In this randomized, open-label, crossover study, 20 KT patients were assigned (1:1) to receive EVL with or without 20 mg atorvastatin for 1 month. One-month washout period was used before crossover. Plasma EVL concentrations were measured by homogeneous particle-enhanced turbidimetric immunoassay. Twelve-hour area under the time-concentration curve (AUC0-12) of EVL was calculated with the use of whole-blood EVL concentrations from 10 different time points (0, 0.5, 1, 1.5, 2, 2.5, 4, 6, 8, and 12 hours). RESULTS: The mean (SD) AUC0-12 for EVL and EVL plus atorvastatin was 155.9 (41.6) ng·h/mL and 151.3 (51.4) ng·h/mL, respectively (P > .05; paired t test). No difference of EVL Cmax or Tmax was found after atorvastatin coadministration. Even though the EVL AUC0-12 levels were not affected by atorvastatin coadministration in one-half of the subjects, for the rest of the patients, there were unpredictable changes in the EVL AUC0-12 levels. This may be due to the high intrapatient variability of EVL drug concentration (coefficient of variation ranges from 9.8% to 34.1%). CONCLUSIONS: Coadministration of atorvastatin with EVL in KT recipients did not affect the pharmacokinetics of EVL.

Glutaraldehyde erythropoietin protects kidney in ischaemia/reperfusion injury without increasing red blood cell production.

BACKGROUND AND PURPOSE: Recombinant human erythropoietin (rHuEPO) is currently the mainstay of renal anaemia treatment. Recently, rHuEPO has been shown to provide pleiotrophic tissue protection in various pathological conditions. However, the benefits of rHuEPO beyond anaemia treatment are limited because it increases red blood cell mass. Carbamylated erythropoietin (CEPO) is the first rHuEPO derivative that lacks erythropoietic activity but retains tissue protection properties. Since carbamylation targets lysine residues on rHuEPo, we hypothesized that targeted lysine modifications of rHuEPO may result in a novel non-erythropoietic erythropoietin. EXPERIMENTAL APPROACH: rHuEPO was subjected to various targeted lysine modifications. In vitro cytoprotection and apoptosis were evaluated using P19 and HEK293 cells. In vivo erythropoiesis was performed by administering the derivatives to animals for 2 weeks. Renoprotection was tested on an ischaemia/reperfusion (I/R) model. KEY RESULTS: We synthesized a novel derivative, a glutaraldehyde erythropoietin (GEPO). This construct abolished in vivo erythropoiesis. Biochemical characterization showed that GEPO was more electrostatically negative than rHuEPO. Immunoprecipitation experiments revealed that GEPO bound to the IL3RB/EPOR heterotrimeric receptor and ameliorated cellular apoptosis via the activation of Bcl-2. Notably, Bcl-2 activation was suppressed by the JAK2 inhibitor, tyrphostin AG490. In vivo experiments showed that GEPO also ameliorated kidney damage due to I/R injury both functionally and histologically. CONCLUSIONS AND IMPLICATIONS: Herein, we describe a novel lysine-modified rHuEPO, glutaradehyde-EPO (GEPO), obtained from a simple reaction. This derivative has no erythropoietic properties but retains cell-protective characteristics both in vitro and in vivo, with promise for future use as an adjunctive treatment of kidney disease.

Endothelial progenitor cells in Asian kidney transplant patients.

BACKGROUND: Endothelial progenitor cells (EPC) involved in endothelial repair and maintenance are restored following renal transplantation. There are scarce data regarding EPC in Asian kidney allograft patients. AIM: We determined the EPC numbers in Thai renal allograft patients to compare with various other parameters. PATIENTS AND METHODS: The EPC numbers which were verified as CD 133+/VEGFR-2 cells in peripheral blood of 38 renal transplant recipients were measured by flow cytometry, and by a cell culture assay using acetylated low-density lipoprotein and Ulex europaeus agglutinin-1 immunofluorescence. Renal function calculated as estimated glomerular filtration rate (eGFR) was obtained by the abbreviated Modification of Diet in Renal Disease (MDRD) formula. RESULTS: Renal allograft patients had lower EPC numbers than normal controls (P < .05). The EPC numbers showed a significant correlation with renal allograft function (P < .05). Recipients with stable eGFR at 12 months of follow-up displayed significantly greater EPC numbers at baseline compared with those subjects who experienced a decline in eGFR (P < .05). Recipients using angiotensin receptor blockers had greater EPC numbers at baseline and better 12-month renal allograft function (P < .05). CONCLUSION: EPC numbers may influence the fate of renal allograft function. Enhancing EPC numbers may be a new strategy to improve long term renal allograft function.

A prevalence of posttransplantation cancers compared with cancers in people with human immunodeficiency virus/acquired immunodeficiency syndrome after highly active antiretroviral therapy.

BACKGROUND: Organ transplant recipients and human immunodeficiency virus & acquired Immunodeficiency Syndrome (HIV/AIDS) patients have immune deficiencies that are possible mechanisms to develop malignancy. The type of cancers associated with these 2 conditions might elucidate this premise. AIM: Our aim was to compare prevalence and type of cancers between kidney transplant recipients and patients with HIV/AIDS. PATIENTS AND METHODS: We retrospectively reviewed 344 patients who underwent kidney transplantation from 1973 to 2007 compared them with 863 subjects with HIV/AIDS at the HIV-Netherlands/Australia/Thailand Research Collaboration (HIV-NAT) from 1997 to 2007. AIDS-defining cancers were excluded from the analysis. We compared the relative tumor risk with the age- and gender- matched general population of metropolitan Bangkok. RESULTS: The overall cancer risk for kidney transplant recipients (standardized incidence ratio [SIR] = 4.21) was comparable with HIV-infected patients (SIR = 3.88). Uroepithelial cancer was the most prevalent type in kidney transplant recipients, whereas cervical cancer was the most common malignancy in HIV-infected patients. The risks of developing hepatoma and non-Hodgkin's lymphoma were comparable between the groups. CONCLUSION: Kidney transplant recipients and HIV-infected patients show increased overall risks of certain types of cancers.

De novo sirolimus-based regimen in Thai renal transplant recipients.

BACKGROUND: Calcineurin inhibitor (CNI) toxicity is a common cause of chronic allograft nephropathy. Although de novo sirolimus (SRL) with CNI minimization may provide better graft function, studies in Asian recipients are lacking. AIM: We sought to determine the 1-year outcomes of renal transplant patients who received a de novo SRL-based regimen with CNI minimization. PATIENTS AND METHODS: A single-center, prospective study of de novo SRL-based, reduced-dose cyclosporine regimen was performed from 2004 to 2007. The control group was a historical cohort of a cyclosporine-based regimen (cyclosporine, prednisolone, and mycophenolate mofetil). The 1-year outcome parameters included renal function, rate of acute rejection, biopsy-proven CNI toxicity, graft and patient survivals. RESULTS: The SRL-based regimen achieved 100% 1-year graft and patient survivals. The renal function was comparable between the SRL-based and CNI-based regimens (serum creatinine 1.32 +/- 0.45 and 1.45 +/- 0.43 mg/dL; P = .27). The rate of biopsy-proven acute rejection was comparable (9.5% and 13%; P = .68). The SRL-based regimen had a higher rate of biopsy-proven CNI toxicity (28.5% and 9.7%; P = .03). CONCLUSIONS: De novo SRL-based regimen with CNI minimization provides excellent transplant outcomes. The strategy to minimize or withdraw CNIs may achieve excellent graft function. A prospective study targeting lower CNI trough levels in Asian transplant recipients is required.

Efficacy of enteric-coated mycophenolate sodium in patients with resistant-type lupus nephritis: a prospective study.

The role of mycophenolate mofetil (MMF) is still controversial in the treatment of cyclophosphamide-resistant proliferative lupus nephritis (PLN). Enteric-coated mycophenolate sodium (EC-MPS) has less gastrointestinal adverse effects than MMF and is, therefore, increasingly utilised in organ transplantation. The aim of this study was to compare the efficacy and safety of EC-MPS versus an extended-course of intravenous cyclophosphamide (ED-IVCY) in resistant-type PLN. Thirty-one, biopsy-proven PLN, patients who failed to respond to an induction of IVCY were enrolled in a prospective, open-labelled, historically controlled study. Patients received 6 month of EC-MPS (720 mg b.i.d.) treatment. The patients in the ED-IVCY group, collected from a database, received a repeated 6-month course of monthly IVCY 0.5-1 g/m(2) of body surface area. Both groups received 0.5-1 mg/kg/day of prednisolone. Primary outcomes were partial or complete responses. A repeated kidney biopsy was performed to evaluate the histological response. No serious adverse events or patient deaths were observed during the study. Both groups had comparable baseline characteristics. At 6 months, the EC-MPS group had a comparable response rate with the ED-IVCY group. There were significantly less adverse events in the EC-MPS group. Repeated biopsies showed significant improvement in the EC-MPS group. EC-MPS provides salutary efficacy and safety in the treatment of resistant-type PLN and can be a suitably alternative treatment to ED-IVCY.

A novel simple hemoglobin dilution technique to measure hemodialysis vascular access flow.

Measurement of the vascular access flow rate (Q(a)) is a widely accepted method for surveillance and predicting access failure. Among current practical methods, the ultrasound dilution technique is standard, but this requires a costly device available in few hemodialysis (HD) centers. Here, we devised a simple hemoglobin dilution technique to accurately measure Q(a) without the need for any special machines. Before HD, values of Q(a) were determined in each of 30 patients by hemoglobin dilution and then, in the same session, by ultrasound dilution. There was a significant correlation between the two techniques using automated hemoglobin and hematocrit or centrifuge-measured hematocrit levels to calculate HD fluid-derived Q(a) values. Our study shows that the HD dilution technique, using no special device, is economical, highly accurate, and easy to perform, and can be used as an alternative to standard ultrasound dilution for vascular access surveillance.

Measurement of urinary chemokine and growth factor messenger RNAs: a noninvasive monitoring in lupus nephritis.

Noninvasive molecular tests of urine cells have been developed to monitor the activity of kidney diseases. We evaluate whether measurement of urinary messenger RNA (mRNA) levels of chemokine and growth factor genes could distinguish between diffuse proliferative lupus nephritis (class IV LN) and others and whether it is able to predict the response to therapy. Prebiopsy urine samples were collected from 26 LN patients. Urine specimens were serially collected over a period of 6 months from class IV LN patients who were receiving standard immunosuppressive treatments. Urinary interferon-producing protein 10 and its CXC chemokine receptor (CXCR)3, transforming growth factor-beta (TGF-beta), and vascular endothelial growth factor (VEGF) mRNA levels were analyzed by quantitative real-time polymerase chain reactions. Levels of chemokine or growth factor mRNAs in urine could distinguish class IV LN from others, with a sensitivity of 85% and a specificity of 94%. The receiver-operative characteristic curve demonstrated that urine mRNA levels of these genes could identify active class IV LN with an accuracy greater than the current available clinical markers, namely systemic lupus erythematosus (SLE) disease activity index, proteinuria, renal function, or urinalysis. A significant reduction of interferon-producing protein 10 (IP-10), CXCR3, TGF-beta, and VEGF mRNA levels from baselines was observed in patients who responded to therapy, whereas the levels tended to increase in those who resisted to treatment. Measurement of urinary chemokine and growth factor mRNAs can precisely distinguish class IV LN from others. Temporal association between these markers and therapeutic response is demonstrated. This noninvasive approach serves as a practical tool in diagnosis and management of LN.

New concepts in organ transplantation.

Long-term graft survival is the desired outcome of organ transplantation. The surrogate metric elimination of acute rejection episodes is not only inadequate but also deceptive, since this freedom does not promise long-term graft survival. Current clinical immunosuppressive agents have reduced acute rejection, but not prolonged graft survival. New paradigms in organ transplantation focus on adhesion-migration events using a selectin antagonist, an antisense oligonucleotide, and FTY 720; on peptide or allochimeric antigens on cytokine disruption, and on inhibition of costimulatory signals. Due to the array of adverse reactions to the available immunosuppressive drugs, these new approaches aim not only to augment long-term graft survival, but also minimize the associated toxicities.

Convective-controlled double high flux hemodiafiltration: a novel blood purification modality.

Convective-controlled double high flux hemodiafiltration (CC-DHF) was set-up using two high flux dialyzers. The convection occurred in the first while the fluid replacement took place in the second dialyzer. The system of CC-DHF basically resembled that of hemodiafiltration. CC-DHF was performed in 9 chronic hemodialysis Thai patients who had been treated with high flux hemodialysis for at least 6 months. When compared with high flux hemodialysis, CC-DHF could provide higher Kt/Vurea (2.4+/-0.4 vs. 2.0+/-0.4, p<0.05) and beta2-microglobulin clearance (106.2+/-15.4 vs. 48.9+/-6.1 ml/min, p<0.01). Following 6-month therapy of CC-HDF, the predialysis beta2-microglobulin levels were reduced by 12.7% while the values of Kt/Vurea were consistently higher than 2.7. The quality of life consistently improved during the 6 months of CC-DHF treatment. There were no differences in clinical and technical complications between CC-DHF and high flux hemodialysis. In conclusion, CC-DHF could provide performance comparable to hemodiafiltration without the need for expensive hemodiafiltration machines.

Monitoring of T-cell subsets in patients treated with anti-CD 25 antibody.

Daclizumab and basiliximab, the antibodies to the interleukin-2 receptor (anti-IL-2R), decrease the incidence of acute rejection in renal transplantation. However, prolonged blockade of IL-2 receptor (IL-2R:CD25) may hamper apoptosis of reactive T-cell clones and thus may obstruct tolerance induction. We determined the effect of varying doses of anti-IL-2R on the number of CD3+CD25+ cells as an index of CD 25 blockade. The number of CD3+CD25+ cells was determined in four groups of induction therapies: no antibody induction; two doses of 50 or 25 mg daclizumab on day 0 and day 14; and two doses of 20 mg basiliximab at day 0 and day 4 (n=10, 24, 10, and 10, respectively). The number of CD3+CD25+ cells were monitored in whole blood before antibody infusion as well as 24 hours thereafter and weekly after transplantation. With two doses of 50 mg daclizumab, two doses of 25 mg daclizumab, and two doses of 20 mg basiliximab, the expression of CD3+CD25+ cells was completely suppressed for 12, 10, and 12 weeks posttransplantation, respectively. The reappearance of CD3+CD25+ cells above the baseline for each induction regimen was: 17 weeks for two doses of 50 mg daclizumab, 11 weeks for two doses of 25 mg daclizumab, and 13 weeks for two doses of 20 mg basiliximab. Monitoring of CD3+CD25+ cells may be utilized to tailor anti-IL-2R administration at a minimal dosage, yet retaining adequate IL-2R blockade for at least 3 months posttransplantation.

Upregulation of IL-2 but not IL-15 by allorecognition in human mixed lymphocyte culture.

The redundant and pleiotropic effects of cytokines in transplant models have been shown both in vitro and in vivo. IL-2 is clearly not necessary for allograft rejection, possibly due to upregulated IL-15. We examined IL-15 expression using mixed lymphocyte culture (MLC) as an allorecognition model. IL-2 and IL-15 levels were measured by enzyme-linked immunoassay after 120 hours of culture. Cell proliferation in MLC was examined using [(3)H]thymidine uptake in the presence of either anti-IL-2Ralpha chain antibody or anti-IL-2Rgamma chain antibody. While IL-2 was detectable in cell supernates of MLC, IL-15 was not. Stimulation with an Anti-IL-2 gamma chain antibody which blocks the IL-2 gamma chain, a common unit in IL-2/IL-15 receptors, failed to produce additive antiproliferative effects after maximum inhibition by anti-IL-2alpha chain antibody, which is specific for IL-2. In conclusion, experiments in the MLC model suggest that allorecognition upregulates IL-2 but not IL-15 expression.

Renal pathology and HIV infection in Thailand.

The existence of a human immunodeficiency virus (HIV)-associated nephropathy (HIVAN) as a distinct disease entity characterized by glomerulosclerosis is well established in North America and Western Europe. Although the large number of HIV-infected cases overwhelm the Asian countries, no cases of HIVAN are documented in the literature. We studied 26 cases of HIV-infected Thai patients with proteinuria greater than 1.5 g/d of protein during 1995 and 1996. None of the patients were treated with antiretroviral drugs at the time of renal biopsy. Intravenous drug addiction and sexual transmission were risk factors in 11 and 15 patients, respectively. Pathological examinations were performed by light microscopic and immunoperoxidase study. Mesangial proliferative glomerulonephritis was found in 17 cases, immunoglobulin A (IgA) nephropathy in 2 cases, and diffuse proliferative glomerulonephritis and interstitial nephritis secondary to cryptococcal infection in 2 cases each. One case each had membranous glomerulopathy, membranoproliferative glomerulonephritis, and granulomatous interstitial nephritis secondary to tuberculosis. The renal pathological findings of HIVAN with the unique features described in previous literature were not evident in these patients. Although the data in this study are limited to 26 HIV-infected Thai patients, we believe that HIVAN is uncommon in the Asian HIV-infected population.

Hepatitis virus and kidney.

Hepatitis A, B and C viruses are major causes of viral hepatitis in human. These infectious agents not only damage liver parenchyma but can also affect renal parenchyma. Hepatitis A virus could produce acute renal failure in a similar fashion to hepatorenal syndrome. Several lines of evidence have shown that chronic hepatitis B virus-infected patients could develop immune complex glomerulopathy. There are convincing data which incriminate hepatitis C virus as the proximate aetiology of certain forms of glomerulonephritis. In post-renal transplanted patients, hepatitis B and C virus could cause increased morbidity and mortality from chronic viral hepatitis. Whether renal transplantation should be performed, either as a donor or as a recipient, in subjects infected with hepatitis B or C virus, is still an issue of controversy.

Granulomatous interstitial nephritis in renal transplant recipient.

Tuberculosis of a transplanted kidney is a rare and serious complication. Search for renal tuberculosis as the cause of deterioration of graft function is mandatory in a renal transplant recipient with tuberculosis of other organs e.g. pulmonary tuberculosis in this patient. Renal histopathology is required for the diagnosis. Treatment with anti-tuberculosis drugs can improve renal function. Drug interactions should be considered when rifampicin is administered with cyclosporin A.