Short-Term Outcomes of ABO-Incompatible Living Donor Kidney Transplantation With Uniform Protocol: Significance of Baseline Anti-ABO Titer

Antibody-mediated rejection (AMR) is one of the major causes of poor outcomes in ABO-incompatible kidney transplantation (ABOi KT). Studies investigating AMR risk factors found that anti-ABO titer is a major issue. However, the significance of antibody titer has been debated. This retrospective study analyzed AMR risk factors in 59 patients who underwent ABOi KT between August 2010 and January 2015. We also analyzed AMR risk factors in recipients with high anti-ABO baseline titers (≥1:64 on dithiothreitol at 37°C phase or ≥1:256 on antihuman globulin phase). The 2-year patient survival rate was 95.8%, and the 2-year graft survival rate was 94.9%. Nine patients (15.3%) experienced clinical (6 of 59 [10.2%]) or subclinical (3 of 59 [5.1%]) AMR. One patient experienced graft loss from hyperacute rejection. AMR risk factor analysis revealed that baseline antibody titer was associated with incidence of AMR. In patients with high baseline titers, low doses of rituximab (200-mg single-dose), an antibody against CD20, was predictive for AMR. Six patients who received pretransplant intravenous immunoglobulin did not experience AMR even when they had high baseline antibody titers. Our results indicate that a high baseline antibody titer affected the incidence of AMR. ABOi KT candidates with high baseline titers need to undergo an intensified preconditioning protocol, including high-dose rituximab (375 mg/m(2)) and intravenous immunoglobulin.

Hormonal differences between female kidney transplant recipients and healthy women with the same gynecologic conditions

BACKGROUND

End-stage renal disease is associated with severe abnormalities in reproductive function. However, the abnormalities are reversed by successful kidney transplantation. The aim of the present study was to compare hormonal levels between recipients with successful kidney transplantations and healthy women with the same gynecologic conditions.

METHODS

The study group consisted of 31 women of reproductive age with end-stage renal disease who underwent successful kidney transplantation. The ratio of the control group, composed of healthy woman, to the study group was 3:1 matched for age and symptoms.

RESULTS

Abnormal bleeding (n = 14) and infertility were the most common gynecologic conditions in kidney transplant recipients. The levels of estrogen (E2) and follicle-stimulating hormone (FSH) in the study group were higher than in the control group, but the levels of progesterone (P4) and luteinizing hormone (LH) were lower in the study group than in the control group. There were no significant differences in prolactin and thyroid-stimulating hormone between the two groups. The incidence of infertility in patients who receive steroid was higher than those with no steroid use (P = .007).

CONCLUSIONS

Compared with healthy age- and symptom-matched women, female kidney transplant recipients have increased levels of E2 and FSH and decreased levels of P4 and LH. These differences in hormone profiles may predispose kidney transplant recipients to increased risk of gynecologic pathologies.

Erlotinib-associated rash correlates with plasma levels at steady state

13008

Background: Erlotinib is a small molecule epidermal growth factor receptor tyrosine kinase inhibitor that is approved for non-small cell lung cancer as a single agent and for pancreatic cancer in combination with gemcitabine. Significant inter-individual variation in drug exposure may explain differential patient outcomes. Genetic polymorphisms of metabolizing enzymes of erlotinib may explain this variability in exposure. Biotransformation assays have implicated cytochrome 3A4/5 (CYP3A4/5) as the predominant metabolizing enzyme. Methods: Patients were enrolled onto a phase-1 dose-escalation study of weekly docetaxel with fixed oral daily dosing (150 mg) of erlotinib. Pharmacodynamic data regarding grade of rash per CTCAE v. 2 were recorded on all 23 patients. Samples for erlotinib pharmacokinetics were obtained after 28 days of continuous daily dosing. Pharmacokinetic (PK) data was attained in 21 patients using LC/MS/MS and analyzed using noncompartmental analysis. Genomic DNA was available for analysis in all 23 patients. Analysis for single nucleotide polymorphisms CYP3A5*3 and CYP2D6*4 were performed by real-time polymerase chain reaction and confirmed by restriction fragment length polymorphism analysis when needed. Results: Average age of patients was 56 (34–76). Nine patients had grade 0–1 rash and 12 had grade 2 rash. As summarized in the table below, the AUC for patients exhibiting grade 2 rash was approximately twice that of patients with grade 0–1 rash. No significant association was found between PK parameters and either CYP3A5 or CYP2D6 polymorphisms. Conclusions: In patients treated with erlotinib the pharmacodynamic endpoint of rash, which has been previously linked with improved patient outcomes, is significantly correlated to the degree of exposure to the drug at steady state. Preliminary data in this small study analyzing pharmacogenetics of erlotinib found no significant correlation between CYP3A5*3 and CYP2D6*4 polymorphic status in either PK or pharmacodynamic measures.

[Table: see text]

[Table: see text]

Effect of panel-reactive antibody positivity on graft rejection before or after kidney transplantation

INTRODUCTION

Because it is well known that kidney transplant recipients with preformed lymphocytotoxic antibodies against HLA antigens have increased graft rejection rates, a serological crossmatch is routinely performed before kidney transplantation. But, the presence of these antibodies is not routinely monitored after transplantation. We investigated the panel-reactive antibody (PRA) response to know whether variations before or after kidney transplantation were associated with graft rejection.

METHODS

We prospectively analyzed sera from 350 renal allograft recipients from September 1998 to March 2003. Pretransplantation and posttransplantation sera at 3 or 5 weeks postoperatively were tested in PRA. Recipients were stratified into 3 groups according to their PRA levels group I, PRA = 0; group II, PRA = less than 50%, and group III, PRA = more than 50%.

RESULTS

The total graft rejection rate among 350 recipients was 9.4% (n = 33). Twenty-four pretransplantation PRA-positive recipients had a graft rejection rate of 20.8% (n = 5), compared with an 8.6% (n = 28) rate among 326 pretransplantation PRA-negative recipients. Six of 24 posttransplantation PRA-positive recipients (25%) experienced a graft rejection versus 27 (8.3%) of 326 posttransplantation PRA-negative subjects. Among the pretransplantation PRA stratae, the rejection rate in group III was 25% (1 of 4) versus 20% (4 of 20) in group II and 8.6% (28 of 326) in group I (P < .05). According to the postransplantation PRA level, 37.5% (3 of 8) in group III versus 18.8% (3 of 16) in group II and 8.3% (27 of 326) in group I (P < .05) had a graft rejection.

CONCLUSION

Our study suggests that the PRA response pretransplantation and in the early posttransplantation period correlates with the kidney allograft rejection rate.

Randomized trial of tacrolimus versus cyclosporine in steroid withdrawal in living donor renal transplant recipients

The introduction of new immunosuppressants has prompted trials of steroid withdrawal. However, several groups have reported a higher incidence of rejection. We conducted a randomized two-arm, parallel-group, open-label, prospective study to compare steroid withdrawal (at 6 months posttransplant) from the regimens of tacrolimus + mycophenolate mofetil (MMF) (FK group) versus cyclosporine + MMF (CSA group). The entry criteria were recipients of first living donor transplants with no diabetes mellitus (DM), congestive heart failure, chronic liver disease, or acute rejection within 6 months posttransplant. The primary endpoint was a biopsy-proven acute rejection episode or treatment failure within 1 year posttransplant. While 87 recipients were assigned to FK (n = 43) and CSA groups (n = 44) before transplantation, 76 recipients (FK 39, CSA 37) could be tapered off steroids at 6 months posttransplant, since 11 were excluded due to acute rejection within 6 months posttransplant (FK two, CSA three) or protocol violations (FK two, CSA four). After steroid withdrawal, the incidence of acute rejection episodes was 0% in the FK group and 13.5% in the CSA group (P < .05). Other results at 12 months posttransplantation were comparable: the incidences of DM 7.8% versus 0% (FK group vs CSA group), hypercholesterolemia 41.0% versus 59.5%, hypertensives 48.7% versus 59.6% as well as the levels of plasma creatinine 1.21 +/- 0.24 versus 1.31 +/- 0.50 mg/dL (P > .05 in every variable). These data suggest that steroid withdrawal is successful in first living donor renal transplant recipients. Tacrolimus may be significantly more effective than cyclosporine to prevent acute rejection after steroid withdrawal.

Prognostic factors affecting graft and patient survival in cadaveric and living kidney transplantation

Numerous studies have reported various prognostic factors that affect graft and patient survival in living and cadaveric donor kidney transplantation (KT). The purpose of this study was to evaluate the clinical outcomes and prognostic factors affecting graft and patient survivals in living and cadaveric donor KT. Between February 1995 and December 2001, 421 patients who had undergone cadaveric donor KT (group I: 216 cases, 51.3%) or living donor KT (group II: 205 cases, 48.7%), were retrospectively analyzed. Five-year overall graft survival rates in living was significantly better than that in cadaveric donor KT, respectively (P = .0234). There was no difference in patient survival rates between the two groups. Such factors as absence of rejection, female donor, female recipient, adult KT according to recipient age (>14 years), and donor serum creatinine level just before transplantation (< 2.5 mg/dL) were significantly associated with good graft survival among cadaveric donor KT, whereas two factors-absence of rejection and adult KT according to recipient age (>14 years)-influenced graft survival in living donor KT. In multivariate analysis, the only significant prognostic factor related to graft survival was the presence of rejection. In conclusion, we suggest that the presence of rejection is the only factor that impairs graft survival in both cadaveric and living donor KT, while other factors affected graft survival differently in the two groups.

Polymerase chain reaction for the diagnosis of human polyomavirus-associated nephropathy in renal transplant recipients

Human polyomavirus type BK may be related to interstitial nephropathy or renal-allograft dysfunction. Patients with nephropathy due to infection with human polyomavirus may be identified early using the polymerase chain reaction(PCR). We attempted to evaluate whether the positive response in the PCR test of BK virus DNA in the plasma of renal transplant recipients affects the function of the renal allograft. Seventy-seven patients were prospectively analyzed according to the operative sex, age, sources of allograft, serum creatinine levels during PCR test for BK virus, postoperative type of immunosuppressant, and presence of graft rejection. Two groups were distinguished according to the PCR result for BK virus: group 1 (n = 12) positive PCR reaction and group 2 (n = 65) negative reaction. The mean follow-up was 32.6 weeks. The incidence of positive PCR tests for BK virus replication after renal transplantation was 15.6%. Decoy cells in the urine were detected in 20.7%. The incidence of BK virus nephropathy was 1.3%. The mean serum creatinine levels of group 1 and 2 at the time of the PCR tests were 1.34 and 1.22, respectively. The rejection rates in group 1 and 2 were 8% and 4.5%, respectively (P > .05). We consider that a PCR assay to detect BK virus in renal recipients blood may be useful to identify patients at risk for nephropathy. It may serve as a noninvasive indicator of BK virus replication, although this study is limited by the short follow-up and small numbers.