How to reduce lethal infectious complications in ABO-incompatible kidney transplantation

Polyoma BK Virus in Kidney Transplant Recipients: Screening, Monitoring, and Management

Polyomavirus BK virus (BKPyV) infection is an important complication of kidney transplantation and allograft failure. The prevalence of viremia is 10%-15%, compared with BK-associated nephropathy (BKPyVAN) at 3%-5%. Given that there are no effective antiviral prophylaxis or treatment strategies for BKPyVAN, active screening to detect BKPyV viremia is recommended, particularly during the early posttransplant period. Immunosuppression reduction to allow viral clearance may avoid progression to severe and irreversible allograft damage. The frequency and duration of screening are highly variable between transplant centers because the evidence is reliant largely on observational data. While the primary treatment goals center on achieving viral clearance through immunosuppression reduction, prevention of subsequent acute rejection, premature graft loss, and return to dialysis remain as major challenges. Treatment strategies for BKPyV infection should be individualized to the recipient's underlying immunological risk and severity of the allograft infection. Efficacy data for adjuvant therapies including intravenous immunoglobulin and cidofovir are sparse. Future well-powered and high-quality randomized controlled trials are needed to inform evidence-based clinical practice for the management of BKPy infection.

Effect of Different Rituximab Doses on B Cell Count, Anti-A/B Antibody Titer, Graft Function, and Infectious Complications in ABO-Incompatible Renal Transplantation: A Prospective Study

BACKGROUND

ABO-incompatible kidney transplantation (ABOiKT) has been accepted as a viable and cost-effective modality with outcomes comparable to ABO-compatible transplants, but there is a concern regarding higher infectious complications in ABOiKT because of the heightened immunosuppression. The desensitization protocol normally includes antibody removal, B cell depletion by rituximab (RTX), and immunomodulation with intravenous immunoglobulin. Efforts have been made over the years to decrease the dose of RTX in an effort to decrease the infective complications. There is limited literature about the minimum effective dose of RTX, which can cause an effective B cell depletion. This prospective study was designed to correlate the RTX dose with peripheral absolute B cell count, graft function, graft and patient survival, and infective complications.

METHODS

This study included 52 adult ABOiKT recipients with anti-A/B antibody titer up to a maximum of 1:512. The participants were divided into 2 groups of 26 each according to the RTX dosage used: Group A received 100 mg/patient, and Group B received 200 mg/patient. RTX was given 14 days prior to transplant after B cell measurement by flow cytometry. The outcomes were compared after 1 year of follow-up.

RESULTS

Both the dosages effectively depleted the absolute B cell count. Although patient survivals, graft survival, graft function, acute rejection episodes, and post-transplant hospital stay were similar in both groups, infective complications were significantly higher in group B.

CONCLUSION

A low dose (100 mg/patient) of RTX produces effective depletion of B cells while lowering the infective complications in ABOiKT.

Acute Rejection and Infectious Complications in ABO- and HLA-Incompatible Kidney Transplantations

Background

Patients receiving ABO-incompatible (ABOi) or human leukocyte antigen (HLA)-incompatible (HLAi) kidney transplantation (KT) require potent immunosuppression and are thus at a higher risk of infectious complications. We evaluated the clinical outcomes of KT stratified by ABO and HLA incompatibilities and identified the factors associated with the clinical outcomes.

Material/Methods

Recipients who underwent living-related KT between 2012 and 2017 were included and classified into 4 groups: ABO-compatible and HLA-compatible (ABOc/HLAc), HLA-incompatible (ABOc/HLAi), ABO-incompatible (ABOi/HLAc), and ABO-incompatible and HLA-incompatible (ABOi/HLAi). Cox proportional hazards regression analyses were carried out to evaluate the risk factors of acute rejection. Out of the 1732 patients who underwent KT, 1190, 131, 358, and 53 were in the ABOc/HLAc, ABOi/HLAc, ABOc/HLAi, and ABOi/HLAi groups, respectively.

Results

The ABO/HLAi group showed the lowest 5-year graft survival rate (91.7%). Death-censored graft survival was not significantly different among the groups. The mortality rate from infections was significantly higher in the ABOi/HLAi group (7.5%) than the other groups. Antibody-mediated rejection-free graft survival was the lowest in the ABOi/HLAi group, with significant differences compared with the ABOi/HLAc group (P=0.02) and the ABOc/HLAi group (P=0.03). ABOi/HLAi (hazard ratio [HR], 2.63; 95% confidence interval [CI], 1.04–6.65; P<0.01) and combined infection (HR, 1.91; 95% CI, 1.45–2.51; P<0.01) were significant risk factors for acute rejection.

Conclusions

Patients with both ABO and HLA incompatibilities showed inferior rates of overall patient and graft survival due to infectious complications. Infection was a prominent risk factor of acute rejection following KT after adjusting for possible confounders including ABO and HLA incompatibility.

Complication from Desensitization

Sensitization to human leukocyte antigens (HLAs) has been one of the major clinical challenges for successful kidney transplantation. In end-stage renal disease, kidney transplantation provides benefits compared with dialysis in terms of improved patient survival better quality of life, and lower ongoing costs after the first year. Living donor kidney transplantation has an advantage with improved allograft survival, and performed earlier and electively compared with deceased donor transplantation. However sensitized patients are increasing in number on transplant waiting lists, and their prospect of getting a transplant is less than nonsensitized patients due to immunological incompatibility with the donor. Strategy for sensitized patients are listing for a compatible deceased donor transplant or, if they have a living donor, either selecting a kidney exchange program or undergoing a desensitization procedure. Desensitization procedures may be undertaken to increase access to either living or deceased donor transplants, and in some situations may also be employed to facilitate participation in a kidney exchange, in less immunological barrier to be overcome. The question of whether individuals are better off with a desensitization treatment followed by HLA-incompatible living donor transplantation or waiting on the deceased donor kidney transplant list for a compatible transplant has recently been addressed by two large multicenter studies, with conflicting results. A multicenter study from the United States published in the New England Journal of Medicine [365;318 326.2011] concluded that there was a strong survival benefit for sensitized patients undergoing desensitization followed by HLA-incompatible living donor kidney transplant compared with those remaining on the waiting list. Of interest, a second study, published in the Lancet, [389;727 734.2017] found no significant survival advantage for desensitized patients compared with similar patients remaining on the waiting list in the United Kingdom. Controversies still remain regarding how desensitization can be achieved and which techniques are effective and safe.

In this chapter various complications from the desensitization will be dealt with in current use of medications or armamentum.

ABO-Incompatible Kidney Transplantation: Low Rates of Infectious Complications and Excellent Patient Survival

BACKGROUND

A significant gap exists between demand and supply of organs for patients with end-stage renal disease. To increase the donor pool, kidney transplantation is performed across ABO- and HLA-incompatible barriers. ABO-incompatible kidney transplant (ABOi-KT) recipients are at increased risk of antibody-mediated rejection, infection, and mortality. Hypogammaglobulinemia secondary to immunosuppression is highly prevalent after solid organ transplantation, and intravenous immunoglobulin (IVIG) has been reported to reduce the risks of infections in various settings. We use high-dose IVIG in ABOi-KT recipients perioperatively. We aimed to determine the rate of infectious complications along with graft and patient survival in our ABOi-KT recipients.

METHODS

We included all adult patients who underwent ABOi-KT from the year 2007 to 2016. Patients received rituximab, plasma exchange, and IVIG (2 g/kg body weight). Thymoglobulin and intravenous methylprednisolone were used as induction treatment. Oral prednisone, mycophenolate mofetil, and tacrolimus were used as maintenance therapy.

RESULTS

A total of 77 ABOi-KTs were performed, and the recipients were followed up for a median of 1557 days. Two patients were diagnosed as having BK nephropathy. No patients were diagnosed as having pneumocystis infection, cytomegalovirus disease, herpes simplex, varicella zoster, or fungal infection. One-year graft and patient survival was 94.8% and 100%, respectively.

CONCLUSIONS

In our series of ABOi-KTs, we observed a low risk of infectious complications and excellent patient survival. High-dose IVIG might have reduced infections.

A Study on the Attitude Toward Kidney Transplantation and Factors Among Hemodialysis Patients in China

BACKGROUND

Kidney transplantation (KT) is the most effective treatment for patients with end-stage renal disease. However, objective data regarding the willingness of patients with end-stage renal disease to undergo transplantation are lacking in China. The purpose of this study was to examine the attitudes and impact factors regarding KT among patients with end-stage renal disease undergoing hemodialysis.

METHODS

This study used a cross-sectional approach. Between June and July 2015, a total of 326 hemodialysis outpatients completed a self-designed questionnaire to assess their attitudes toward KT and satisfaction with dialysis.

RESULTS

Patients' mean age was 49.47 years, and the mean duration of hemodialysis was 52 months. Among these patients, 34.9% would like to undergo transplantation, and 4.23% of patients have a potential related living donor. Among the patients wishing to undergo transplantation, 43.93% had started a procedure to be grafted. The minority of patients (45.93%) stated that KT offers a better quality of life; 78.5% believe that it is more expensive than hemodialysis. Overall, 13.36% of patients are willing to become organ donors after death. The main motivating factor for KT was because of study or work difficulties (56.1%). The effects of the following 7 independent variables on attitude were assessed: age, education level, monthly income, sex, duration of hemodialysis, dialysis satisfaction, and reimbursement level.

CONCLUSIONS

To improve hemodialysis patients' accessibility to KT, better information must be provided to patients, their families, and other support providers. Transplantation is the best treatment for patients undergoing hemodialysis, which should be given more attention and political support economically and publicly by the government and some closely related agencies.

Impact of ABO incompatible kidney transplantation on living donor transplantation

Background

ABO incompatible kidney transplantation (ABOi-KT) is an important approach for overcoming donor shortages. We evaluated the effect of ABOi-KT on living donor KT.

Methods

Two nationwide transplantation databases were used. We evaluated the impact of ABOi-KT on overall living donor transplant activity and spousal donation as subgroup analysis. In addition, we compared the clinical outcome between ABOi-KT and ABO compatible KT (ABOc-KT) from spousal donor, and performed a Cox proportional hazards regression analysis to define the risk factors affecting the allograft outcomes.

Result

The introduction of ABOi-KT increased overall living donor KT by 12.2% and its portion was increased from 0.3% to 21.7% during study period. The ABOi-KT in living unrelated KT was two times higher than that of living related donor KT (17.8 vs.9.8%). Spousal donor was a major portion of living unrelated KT (77.6%) and ABOi-KT increased spousal donation from 10% to 31.5% in living donor KT. In addition, increasing rate ABOi-KT from spousal donor was 10 times higher than that of living related donor. The clinical outcome (incidence of acute rejection, allograft function, and allograft and patient survival rates) of ABOi-KT from spousal donor was comparable to that of ABOc-KT. Neither ABO incompatibility nor spousal donor was associated with acute rejection or allograft failure on multivariate analysis.

Conclusions

ABOi-KT increased overall living donor KT, and ABOi-KT from spousal donor is rapidly increasing with favorable clinical outcomes.

Ongoing higher infection rate in ABO-incompatible kidney transplant recipient: is it a serious problem? A single-center experience

Purpose

Additional clinical experience and knowledge regarding the barrier to transplantation of ABO blood type incompatibility could reduce the higher rate of infectious complications in ABO-incompatible kidney transplantation.

Methods

A total of 79 ABO-incompatible kidney transplantation (ABOiKT) patients were compared with 260 ABO-compatible kidney transplantation (ABOcKT) patients for basic clinical characteristics, infectious complications, rejection episodes, and graft survival.

Results

There were no significant differences in baseline characteristics, rejection rates, or graft survival between the ABOiKT and ABOcKT patients. No significant difference in the infection rate was shown for cytomegalovirus (26.6% vs. 30.0%; P = 0.672), BK virus (19.0% vs. 21.5%; P = 0.752), herpes disease (10.1% vs. 5.0%; P = 0.082), pneumonia (5.3% vs. 3.8%; P = 0.746), or urinary tract infection (8.9% vs. 10.0%; P > 0.999). Female sex (hazard ratio [HR], 2.20; P = 0.003), advanced age (≥60 years) (HR, 2.5; P = 0.019), history of rejection episodes (HR, 2.28; P = 0.016), and history of surgical complications (HR, 4.64; P = 0.018) were significant risk factors for infection. ABO incompatibility demonstrated a tendency toward higher infection risk without statistical significance (HR, 1.74; P = 0.056).

Conclusion

In spite of immunosuppressant protocol modification, the rate of infectious complications following ABOiKT is still higher than with ABOcKT when a modified desensitization protocol is used. However, this was not sufficient to avoid ABOiKT.