Cytomegalovirus infection after acute rejection therapy in seropositive kidney transplant recipients

Management of cytomegalovirus in adult solid organ transplant patients: GESITRA-IC-SEIMC, CIBERINFEC, and SET recommendations update

Cytomegalovirus (CMV) infection remains a significant challenge in solid organ transplantation (SOT). The last international consensus guidelines on the management of CMV in SOT were published in 2018, highlighting the need for revision to incorporate recent advances, notably in cell-mediated immunity monitoring, which could alter the current standard of care. A working group including members from the Group for the Study of Infection in Transplantation and the Immunocompromised Host (GESITRA-IC) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) and the Spanish Society of Transplantation (SET), developed consensus-based recommendations for managing CMV infection in SOT recipients. Recommendations were classified based on evidence strength and quality using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The final recommendations were endorsed through a consensus meeting and approved by the expert panel.

Prevention of Cytomegalovirus Infection in Solid Organ Transplant Recipients: Guidelines by the Korean Society of Infectious Diseases and the Korean Society for Transplantation

Cytomegalovirus (CMV) is the most important opportunistic viral pathogen in solid organ transplant (SOT) recipients. The Korean guideline for the prevention of CMV infection in SOT recipients was developed jointly by the Korean Society for Infectious Diseases and the Korean Society of Transplantation. CMV serostatus of both donors and recipients should be screened before transplantation to best assess the risk of CMV infection after SOT. Seronegative recipients receiving organs from seropositive donors face the highest risk, followed by seropositive recipients. Either antiviral prophylaxis or preemptive therapy can be used to prevent CMV infection. While both strategies have been demonstrated to prevent CMV infection post-transplant, each has its own advantages and disadvantages. CMV serostatus, transplant organ, other risk factors, and practical issues should be considered for the selection of preventive measures. There is no universal viral load threshold to guide treatment in preemptive therapy. Each institution should define and validate its own threshold. Valganciclovir is the favored agent for both prophylaxis and preemptive therapy. The evaluation of CMV-specific cell-mediated immunity and the monitoring of viral load kinetics are gaining interest, but there was insufficient evidence to issue recommendations. Specific considerations on pediatric transplant recipients are included.

Epidemiology, management, and burden of cytomegalovirus in solid organ transplant recipients in selected countries outside of Europe and North America: A systematic review

BACKGROUND

Cytomegalovirus (CMV) is a frequent infectious complication following solid organ transplantation (SOT). Considering significant differences in healthcare systems, a systematic review was conducted to describe the epidemiology, management, and burden of CMV post-SOT in selected countries outside of Europe and North America.

METHODS

MEDLINE, Embase, and Cochrane databases were searched for observational studies in SOT recipients across 15 countries in the regions of Asia, Pacific, and Latin America (search period: January 1, 2011 to September 17, 2021). Outcomes included incidence of CMV infection/disease, recurrence, risk factors, CMV-related mortality, treatment patterns and guidelines, refractory and/or resistant CMV, patient-reported outcomes, and economic burden.

RESULTS

Of 2708 studies identified, 49 were eligible (n = 43/49; 87.8% in adults; n = 34/49, 69.4% in kidney recipients). Across studies, selection of CMV preventive strategy was based on CMV serostatus. Overall, rates of CMV infection (within 1 year) and CMV disease post-SOT were respectively, 10.3%-63.2% (9 studies) and 0%-19.0% (17 studies). Recurrence occurred in 35.4%-41.0% cases (3 studies) and up to 5.3% recipients died of CMV-associated causes (11 studies). Conventional treatments for CMV infection/disease included ganciclovir (GCV) or valganciclovir. Up to 4.4% patients were resistant to treatment (3 studies); no studies reported on refractory CMV. Treatment-related adverse events with GCV included neutropenia (2%-29%), anemia (13%-48%), leukopenia (11%-37%), and thrombocytopenia (13%-24%). Data on economic burden were scarce.

CONCLUSION

Outside of North America and Europe, rates of CMV infection/disease post-SOT are highly variable and CMV recurrence is frequent. CMV resistance and treatment-associated adverse events, including myelosuppression, highlight unmet needs with conventional therapy.

Cytomegalovirus in renal transplant recipients from living donors with and without valganciclovir prophylaxis and with immunosuppression based on anti-thymocyte globulin or basiliximab

BACKGROUND

In our population, anti-thymocyte globulin (ATG) of 1 mg/Kg/day for 4 days is used; which permits not using valgancyclovir (VGC) prophylaxis in some renal transplant recipients (RTR) with moderate risk (R+), to reduce costs. This study aimed to determine the incidence and risk of developing cytomegalovirus (CMV), with or without prophylaxis, when exposed to low doses of ATG or basiliximab (BSL).

PATIENTS AND METHODS

A retrospective cohort included 265 RTR with follow-up of 12 months. Prophylaxis was used in R-/D+ and some R+. Tacrolimus (TAC), mycophenolate mofetil, and prednisone were used in all patients. Logistic regression analysis was performed to estimate the risk of CMV in RTR with or without VGC.

RESULTS

Cytomegalovirus was documented in 46 (17.3%) patients: 20 (43.5%) with CMV infection, and 26 (56.5%) with CMV disease. Anti-thymocyte globulin was used in 39 patients (85%): 32 R+, six D+/R-, and one D-/R-. ATG was used in 90% (27 of 30) of patients with CMV and without prophylaxis. The multivariate analysis showed an association of risk for CMV with the absence of prophylaxis (RR 2.29; 95% CI 1.08-4.86), ATG use (RR 3.7; 95% CI 1.50-9.13), TAC toxicity (RR 3.77; 95% CI 1.41-10.13), and lymphocytes at the sixth post-transplant month (RR 1.77; 95% CI 1.0-3.16).

CONCLUSIONS

Low doses of ATG favored the development of CMV and a lower survival free of CMV compared with BSL. In scenarios where resources for employing VGC are limited, BSL could be an acceptable strategy.

Epidemiology, risk factors, and outcomes associated with cytomegalovirus in adult kidney transplant recipients: A systematic literature review of real-world evidence

Kidney transplant recipients (KTRs) have increased risk for cytomegalovirus (CMV) infection/disease given the necessity of drug-induced immunosuppression. A comprehensive review of published literature reporting real-world data on prevention strategies utilized and associated CMV burden outcomes is limited. Such data could help inform future clinical practice and identify unmet needs in CMV management. We conducted a systematic review of observational studies published in Medline or EMBASE from January 2008 to November 2018 to identify current real-world CMV management approaches, CMV infection/disease risk factors, and outcomes associated with CMV infection. Descriptive statistics and pooled quantitative analyses were conducted. From 1608 records screened, 86 citations, including 69 803 adult KTR, were included. Prophylaxis and preemptive therapy (PET) were predominant approaches among D+/R- and R + CMV serostatus transplants, respectively. Valganciclovir and ganciclovir were frequently utilized across CMV risk strata. Despite prevention approaches, approximately one-fourth of KTR developed CMV infection. Age and D+/R- CMV serostatus were consistent risk factors for CMV infection/disease. CMV infection/disease was associated with increased mortality and graft loss. CMV was similarly associated with acute rejection (AR) risk, but with high heterogeneity among studies. Limited data were available on CMV and opportunistic infections (OIs) risk. CMV remains a significant issue. New strategies may be needed to optimize CMV management.

The risk of cytomegalovirus infection after treatment of acute rejection in renal transplant recipients

The risk of cytomegalovirus infection (CMV) after rejection treatment is poorly understood. To investigate this, we conducted a case/control (1:2) analysis of adult renal transplant recipients between January 1, 2005 and December 31, 2015, via incidence density sampling and survival analysis. Our objective was to evaluate the association of prior acute rejection with subsequent CMV, including epidemiology and outcomes. There were 2481 eligible renal transplants within the study period and 251 distinct CMV infections. Despite the use of antiviral prophylaxis rejection was a significant risk factor for CMV on unadjusted (HR 1.73 [1.34, 2.24] P < 0.05) and adjusted analysis (HR 1.46 [1.06, 2.04] P < 0.05). When matching cases to controls patients with CMV had significantly more rejection prior to CMV diagnosis (26.7% vs 14.2%, P < 0.01). CMV was associated with a twofold increased risk of prior rejection on unadjusted (OR 1.94, 95%CI: 1.28-2.96, P < 0.01) and adjusted analysis (OR 2.16, 95% CI: 1.31-3.58, P < 0.01). Patients with rejection preceding CMV had significantly increased graft loss (HR 2.89, 95% CI: 1.65-5.09, P < 0.01) and mortality (HR 1.82, 95% CI: 1.12-4.24, P = 0.03) as compared to those CMV cases without rejection. In conclusion, rejection is a risk factor for CMV infection that appears to persist for 1 year. Preceding rejection events increased risk of graft loss and mortality in CMV patients. Given this, prolonged surveillance monitoring for CMV after rejection may be warranted. Studies are needed investigating optimal monitoring strategies.

The Third International Consensus Guidelines on the Management of Cytomegalovirus in Solid-organ Transplantation

Despite recent advances, cytomegalovirus (CMV) infections remain one of the most common complications affecting solid organ transplant recipients, conveying higher risks of complications, graft loss, morbidity, and mortality. Research in the field and development of prior consensus guidelines supported by The Transplantation Society has allowed a more standardized approach to CMV management. An international multidisciplinary panel of experts was convened to expand and revise evidence and expert opinion-based consensus guidelines on CMV management including prevention, treatment, diagnostics, immunology, drug resistance, and pediatric issues. Highlights include advances in molecular and immunologic diagnostics, improved understanding of diagnostic thresholds, optimized methods of prevention, advances in the use of novel antiviral therapies and certain immunosuppressive agents, and more savvy approaches to treatment resistant/refractory disease. The following report summarizes the updated recommendations.

Is antibody-mediated rejection in kidney transplant recipients a risk factor for developing cytomegalovirus or BK virus infection? Results from a case-control study

BACKGROUND

Data are scarce on cytomegalovirus (CMV) and BK virus (BKV) infection after antibody-mediated rejection (ABMR).

OBJECTIVES

We hypothesized that the immunological response in patients with ABMR or the immune modulation associated with its treatment could predispose to CMV and BKV infection. Our objective was to investigate this hypothesis.

STUDY DESIGN

We conducted a single-center, matched case-control study (1:2 ratio) to analyze CMV and BKV replication during the first year after the ABMR diagnosis in kidney transplant recipients. Adult recipients with a histopathological diagnosis of ABMR between 2007-2015 were included as cases. Controls were kidney recipients who underwent transplantation immediately before and after the index case.

RESULTS

Fifty-eight patients diagnosed with ABMR (33 chronic active ABMR and 25 acute ABMR), with their matched controls (116) were included. Forty-four cases received treatment for ABMR, including plasmapheresis (41), immunoglobulins (40), and rituximab (31). Within 1 year after ABMR, cases showed CMV replication more often than controls (9/58, 15.5% vs 7/116, 6%, OR = 4.21, CI 1.10-16.16, p = 0.04). Over the study period, CMV PCR determinations were requested more frequently in cases than controls (46/58, 79.3% vs 63/116, 54.3%, OR = 4.58, CI 1.92-10.9, p = 0.001). On multivariate analysis adjusted for CMV PCR determinations, retransplantation, antithymocyte globulin treatment and methylprednisolone treatment for acute rejection, CMV replication remained more common in cases than in controls (OR = 2.41, CI 0.49-11.73, p = 0.28). There were no differences in BKV replication in either urine or blood.

CONCLUSIONS

ABMR may be a risk factor for CMV but not for BKV replication in kidney transplant recipients.

Targeted preemptive therapy according to perceived risk of CMV infection after kidney transplantation

Background

Methods

Results

Conclusion

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.

Four-Year Analyses of Renal Graft Biopsies: A Single-Center Pathology Experience

OBJECTIVES

Kidney transplant is the best treatment for patients with end-stage renal disease. Long-term graft survival depends on the protection of renal allograft function. Renal allograft biopsy is the most important method for examining an allograft function. Biopsy provides critical information, enabling diagnosis and grading of pathologic changes, prediction of response to therapy, and long-term graft prognosis.

MATERIALS AND METHODS

We reviewed the medical records of patients who underwent renal transplant from living and deceased donors at Baskent University Adana Teaching and Research Hospital between 2010 and 2014 and who had an indication for biopsy. Clinical characteristics and laboratory results of patients were recorded. Patient biopsy samples were examined according to the Banff 2009 classification.

RESULTS

Between 2010 and 2014, there were 175 renal transplants performed at our hospital, with 134 recipients (76.6%) having living-donor and 41 recipients (23.4%) having deceased-donor transplants. Fifty-one patients (29.1%) were children, and 124 patients (70.9%) were adults. We found that there were 123 biopsies made from 75 transplant patients over a 4-year period. When examined according to Banff 2009 criteria, the biopsy samples revealed acute T-cell-mediated rejection alone in 14.1% of the samples, acute antibody-mediated rejection in 4%, and a combination of the 2 rejections in 5.7%. Specific infections were detected in 12 patients. The graft nephrectomy rate was 5.1%.

CONCLUSIONS

This study investigated biopsy results, their relation with patient clinical status and 4-year survival rates, and our pathology experience and found that rejection and infection rates were similar to the literature. Our future studies with a longer follow-up and a larger sample size will likely provide more accurate information about graft survival and biopsy results.

In Kidney Transplant Recipients With a Positive Virtual Crossmatch, High PRA was Associated With Lower Incidence of Viral Infections

BACKGROUND

There is little information on the incidence, risk factors, and outcomes associated with CMV and BK infections in sensitized patients.

METHODS

We examined 254 consecutive kidney transplant recipients with positive virtual crossmatch and negative flow crossmatch.

RESULTS

A total of 111 patients (43%) developed CMV disease or BK infection or nephropathy (BKVN). Specifically, 78 patients (30.7%) developed BK infection, 19 (7.5%) had BKVN, and 33 (12.9%) presented with CMV disease. Four patients (1.5%) developed both infections. Mean time from transplant to diagnosis for BK and CMV was 4.07 ± 3.10 and 8.35 ± 5.20 months, respectively. African American (HR, 2.64; 95% CI, 1.37-5.07; P = 0.003), thymoglobulin induction (HR, 2.18; 95% CI, 1.38-3.43; P = 0.0008), DSA greater than 500 MFI at transplant (HR, 1.64; 95% CI, 1.05-2.57; P = 0.03), history of diabetes (HR, 1.62; 95% CI, 1.01-2.60; P = 0.04), CMV D+/R- (HR, 2.30; 95% CI, 1.06-5.01; P = 0.03), and acute rejection (HR, 1.49; 95% CI, 0.99-2.24; P = 0.05) were associated with increase incident of BK/CMV, whereas rituximab (HR, 0.47; 95% CI, 0.24-0.91; P = 0.02), peak PRA greater than 80% (HR, 0.48; 95% CI, 0.27-0.84; P = 0.01), and living donor transplant (HR, 0.57; 95% CI, 0.36-0.87; P = 0.01) were associated with a lower likelihood of infection. Thymoglobulin induction (HR, 2.50; 95% CI, 1.02-6.13; P = 0.04), and peak PRA greater than 80% (HR, 0.45; 95% CI, 0.23-0.86; P = 0.02) remained significant predictors of infection after multivariate adjustment.

CONCLUSIONS

Although more than 40% of patients with a positive virtual crossmatch presented with BK infection/CMV disease, high PRA greater than 80% seemed to be protective.

Low dose of mycophenolate mofetil is enough in desensitized kidney transplantation using rituximab

Background

Rituximab is widely used in kidney transplantation. However, it is not clear whether the conventional doses of maintenance immunosuppressant in rituximab-treated kidney transplantation (KT) are appropriate. In our previous study, decreasing mycophenolate mofetil (MMF) dose due to infection did not increase the incidence of rejection or graft failure. Based on these experiences, we developed a new protocol with a lower dose of MMF and studied its clinical outcomes in rituximab-treated KT.

Methods

We enrolled all patients who underwent ABO-incompatible or human leukocyte antigen (HLA)-sensitized living donor KT with the new immunosuppressant protocol after preconditioning with rituximab, but without splenectomy from November 2011 to May 2013. Seventy-two patients (group 1) were consecutively enrolled in this study and followed until November 2013. Patients from our previous study served as control groups. Sixty-seven patients received KT using rituximab with a conventional dose of MMF (group 2), and 87 patients received ABO compatible KT without need for rituximab (group 3). Clinical outcomes, including rejection, infection, and graft survival, were compared between the groups. The χ² test and Fisher’s exact test were used for categorical variables, the Student’s t-test and Mann-Whitney U test were used for continuous variables, and a log-rank test was used for mortality analysis.

Results

Doses of postoperative MMF (g/day) were lower in group 1 than in the other groups (1.03 ± 0.19, 1.48 ± 0.34 and 1.48 ± 0.32 g/day at 1 week, p < 0.001). Infectious complications occurred more often in groups with conventional MMF doses (group 2 and 3) than in group 1 (16.7 vs. 37.3 %, p = 0.007 and 16.7 vs. 34.5 %, p = 0.012, respectively). Notably, group 1 showed a lower incidence of cytomegalovirus infection than group 2. However, reduction in MMF dose did not increase the incidence of acute rejection (4.2, 4.5 and 10.3 %). Only one graft failure occurred in group 2 due to vessel kinking after operation. There were no significant differences in the incidence of malignancy and mortality between groups.

Conclusions

A low MMF dose reduces infection without increasing rejection or graft loss and it may be appropriate to reduce the dose of MMF for rituximab-treated KT patients.

Reduced Incidence of Cytomegalovirus Infection in Kidney Transplant Recipients Receiving Everolimus and Reduced Tacrolimus Doses

This study compared the incidence of CMV infection/disease in de novo kidney transplant recipients receiving everolimus or mycophenolate and no CMV pharmacological prophylaxis. We randomized 288 patients to receive a single 3 mg/kg dose of antithymocyte globulin, tacrolimus, everolimus, and prednisone (r-ATG/EVR, n = 85); basiliximab, tacrolimus, everolimus, and prednisone (BAS/EVR, n = 102); or basiliximab, tacrolimus, mycophenolate, and prednisone (BAS/MPS, n = 101). The primary end-point was the incidence of first CMV infection/disease in the intention-to-treat population at 12 months. Patients treated with r-ATG/EVR showed a 90% proportional reduction (4.7% vs. 37.6%, HR 0.10, 95% CI 0.037-0.29; p < 0.001), while those treated with BAS/EVR showed a 75% proportional reduction (10.8% vs. 37.6%, HR 0.25, 95% CI 0.13-0.48; p < 0.001) in the incidence of CMV infection/disease compared to BAS/MPS. There were no differences in the incidence of acute rejection (9.4 vs. 18.6 vs. 15.8%, p = 0.403), wound-healing complications, delayed graft function, and proteinuria. Mean estimated glomerular filtration rate was lower in BAS/EVR (65.7 ± 21.8 vs. 60.6 ± 20.9 vs. 69.5 ± 21.5 ml/min, p = 0.021). In de novo kidney transplant recipients receiving no pharmacological CMV prophylaxis, reduced-dose tacrolimus and everolimus was associated with a significant reduction in the incidence of CMV infection/disease compared to standard tacrolimus dose and mycophenolate (ClinicalTrials.gov NCT01354301).

Cytomegalovirus post kidney transplantation: prophylaxis versus pre-emptive therapy?

Cytomegalovirus is the most important pathogen causing opportunistic infections in kidney allograft recipients. The occurrence of CMV disease is associated with higher morbidity, higher incidence of other opportunistic infections, allograft loss and death. Therefore, an efficient strategy to prevent CMV disease after kidney transplantation is required. Two options are currently available: pre-emptive therapy based on regular CMV PCR monitoring and generalized antiviral prophylaxis during a defined period. In this review, we describe those two approaches, highlight the distinct advantages and risks of each strategy and summarize the four randomized controlled trials performed in this field so far. Taken this evidence together, pre-emptive therapy and anti-CMV prophylaxis are both equally potent in preventing CMV-associated complications; however, the pre-emptive approach may have distinct advantages in allowing for development of long-term anti-CMV immunity. We propose a risk-adapted use of these approaches based on serostatus, immunosuppressive therapy and availability of resources at a particular transplant centre.