Delayed graft function and rejection are risk factors for cytomegalovirus breakthrough infection in kidney transplant recipients

Terminally differentiated effector memory T cells in kidney transplant recipients: New crossroads

Immunosenescence, the age-related dysregulation of innate and adaptive immunity, impairs immune response and increases inflammation, leading to higher infection and cardiovascular risks, particularly outside the field of transplantation. In kidney transplant recipients (KTRs), conditions like cytomegalovirus infection, old age, uremia, smoking, and diabetes, linked to poor outcomes, are associated with enhanced immunosenescence. Recent studies highlight the pathogenic role of cytotoxic T cells, particularly terminally differentiated effector memory T cells that reexpress CD45RA (TEMRA), in graft dysfunction. A higher proportion of circulating CD8+ TEMRA cells is observed in KTRs with chronic rejection. In antibody-mediated rejection, they invade the graft by superior chemotactic properties and binding to human leukocyte antigen (HLA) antibodies through FcγRIIIa (CD16). Also in microvascular inflammation without donor-specific antibodies, and even in patients without rejection but faster decline of kidney function, intragraft CD8+ TEMRA cells were instrumental. CD8+ TEMRA cells may explain the unresolved dismal graft outcomes associated with donor age and cytomegalovirus-serostatus mismatching and could become a novel therapeutic target in KTRs.

Challenges for the improvement of valganciclovir prophylaxis in solid organ transplantation and the possible role of therapeutic drug monitoring in adults

Cytomegalovirus (CMV) infection frequently occurs after solid organ transplantation and is associated with an increased morbidity and mortality. Fortunately, the development of valganciclovir prophylaxis has lowered the incidence of CMV infection and its complications in immunosuppressed solid organ transplant recipients. However, breakthrough infections during valganciclovir prophylaxis and late CMV infection after cessation of valganciclovir prophylaxis still occur with the current prophylactic strategy. Additionally, valganciclovir resistance has emerged among CMV strains, which complicates the treatment of CMV infections. Furthermore, the use of valganciclovir is associated with myelotoxicity, which can lead to the premature withdrawal of prophylaxis. It is important to address these current issues in order to improve the standard care after solid organ transplantation. This paper will therefore discuss the clinical practice of valganciclovir prophylaxis, elaborate on its issues and suggest how to improve the current prophylactic strategy with a possible role for therapeutic drug monitoring.

Delayed Graft Function Among Kidney Transplant Recipients Is Associated With an Increased Risk of Urinary Tract Infection and BK Viremia

Background

Delayed graft function (DGF) among deceased donor kidney transplant recipients (DDKTRs) is a well-known risk factor for allograft rejection, decreased graft survival, and increased cost. Although DGF is associated with an increased risk of rejection, it is unclear whether it also increases the risk of infection.

Methods

We reviewed all adult DDKTRs at our center between 2010 and 2018. The primary outcomes of interest were BK viremia, cytomegalovirus viremia, pneumonia, and urinary tract infection (UTI) within the first year of transplant. Additional analysis was made with censoring follow-up at the time of allograft rejection.

Results

A total of 1512 DDKTRs were included, of whom 468 (31%) had DGF. As expected, several recipient, donor, and baseline immunological characteristics differed by DGF status. After adjustment, DGF was significantly associated with an increased risk of BK viremia (hazard ratio: 1.34; 95% confidence interval, 1.0-1.81; P = 0.049) and UTI (hazard ratio: 1.70; 95% confidence interval, 1.31-2.19; P < 0.001) but not cytomegalovirus viremia or pneumonia. Associations were similar in models censored at the time of rejection.

Conclusions

DGF is associated with an increased risk of early infectious complications, mainly UTI and BK viremia. Close monitoring and appropriate management are warranted for better outcomes in this unique population.

The effect of late-onset CMV infection on the outcome of renal allograft considering initial graft function

BACKGROUND

Delayed graft function (DGF) increases the renal allograft failure risk. Late-onset Cytomegalovirus (CMV) infection's effect on the association between DGF and allograft failure has not been determined.

METHODS

In this retrospective cohort, we included all renal allograft recipients at London Health Sciences Centre from January 1, 2014 to December 30, 2017, and continued clinical follow-up until February 28, 2020. We determined whether late-onset CMV infection affects the association between DGF and allograft failure in stratified and Cox proportional hazard analyses.

RESULTS

Of 384 patients (median age [interquartile range]: 55 [43.3-63]; 38.7% female), 57 recipients (14.8%) were diagnosed with DGF. Patients with DGF were at a greater risk of CMV infection than patients without DGF (22.8% vs. 11.3%, p = .017). Late-onset CMV infection (odds ratio [OR]: 4.7, 95% CI: 2.07-10.68) and rejection (OR: 9.59, 95% CI: 4.15-22.16) significantly increased the risk of allograft failure in recipients with DGF. Patients with DGF had a significantly greater risk of graft failure than those without DGF (17.5% vs. 6.1%, p = .007). In the adjusted Cox hazard model, CMV infection significantly increased the risk of allograft failure (aHR: 3.19, 95% CI: 1.49-6.84).

CONCLUSION

Late-onset CMV infection considerably increased the risk of graft failure in patients with DGF. A hybrid preventive model including prophylaxis followed by CMV-specific cell-mediated immunity monitoring may decrease the risk of allograft failure in recipients with DGF.

Cytomegalovirus infection in transplant recipients: newly approved additions to our armamentarium

BACKGROUND

The burden that cytomegalovirus (CMV) portends for haematopoietic and solid-organ transplant recipients cannot be understated. Valganciclovir and ganciclovir have successfully been used for prevention and treatment of CMV infections, although with serious side effects such as leucopenia and some development of resistance. Until recently, available therapies for ganciclovir-resistant CMV have significant toxicities. Although advances have been made in the field, the unmet medical needs for effective and well-tolerated therapies are significant.

OBJECTIVES

This review aims to summarise the current and emerging CMV antiviral drugs and discusses future perspectives in the field.

SOURCES

We searched for relevant articles with pertinent keywords: "Cytomegalovirus OR CMV", "Transplant" and "Antiviral". Articles published after 2019 were given preference. Articles were reviewed by the authors for relevance and impact to the subject of interest.

CONTENT

We outline in this review current advances in prophylaxis of CMV infection with letermovir, breakthrough CMV infections while on or after prophylaxis, the development of resistant and refractory CMV infections, and the newly approved anti-CMV agent, maribavir, in haematopoietic and solid-organ transplant recipients.

IMPLICATIONS

Prevention of CMV infections after transplant has improved greatly over the past few years. Despite major advancements, breakthrough CMV infections and development of refractory and resistant CMV infections remain major complications post transplantation. We highlight emerging therapeutics that tolerably and effectively prevent and treat CMV infections, especially refractory and resistant cases.

Risk factors for cytomegalovirus infection and disease after kidney transplantation: A meta-analysis

OBJECTIVE

To investigate the risk factors for cytomegalovirus (CMV) infection and disease in kidney transplantation recipient, and provide references for the prevention and control of CMV infection and disease in kidney transplantation patients.

METHODS

Chinese and international literature related to risk factors for CMV infection and disease in renal transplant recipients was searched using databases, including China National Knowledge Infrastructure; WanFang Data; Wiper; Chinese Biomedical Literature database; PubMed; Embase; Web of Science, and the Cochrane Register of Controlled Trials. Two researchers independently screened the literature, extracted the data, and evaluated the quality of the literature according to published standards. A meta-analysis was performed using RevMan 5.4 software to extract the risk factors for CMV infection and disease in renal transplant recipients.

RESULTS

A total of 59,847 subjects were included in 24 studies. The risk factors for CMV infection were ATG [OR = 2.76, 95% CI (2.10, 3.63), P < 0.00001], Donor (D) CMV-IgG(+) Receptor (R)(-): (D+/R-) [OR = 2.97, 95% CI (1.63, 5.44), P = 0.004 < 0.05], recipient age [OR = 1.96, 95% CI (1.50, 2.54), P < 0.00001], lymphocytopenia [OR = 3.26, 95% CI (1.46, 7.31), P < 0.00001], and mycophenolate [OR = 3.22, 95% CI (2.02, 5.46), P < 0.00001]. The protective factor for CMV infection was glomerular filtration rate (GFR) [OR = 0.98, 95% CI (0.97, 0.99), P < 0.00001], and the uncertain factors were the use of tacrolimus [OR = 0.91, 95% CI (0.64, 1.28), P = 0.58 > 0.05], rejection [OR = 1.32, 95% CI (0.49, 3.53), P = 0.58 > 0.05], donor age [OR = 1.00, 95% CI (0.99, 1.01), P = 0.67 > 0.5], and preemptive therapy [OR = 0.51, 95% CI (0.11, 2.36), P = 0.86 > 0.05]. The risk factors for CMV disease were D+/R- [OR = 4.78, 95% CI (3.76, 6.07), P < 0.00001], ATG [OR = 1.83, 95% CI (1.25, 2.67), P < 0.00001], rejection [OR = 1.42, 95% CI (1.26, 1.59), P < 0.00001], mycophenolate [OR = 1.67, 95% CI (1.38, 2.02), P < 0.00001], recipient age [OR = 1.03, 95% CI (1.02, 1.03), P < 0.00001], donor age [OR = 1.01, 95% CI (1.00, 1.01), P = 0.001 < 0.05], Donor (D) CMV-IgG(+) Receptor(R)(+): (D+/R+) [OR = 1.92, 95% CI (1.49, 2.46), P < 0.00001], the use of prednisolone [OR = 1.59, 95% CI (1.32, 1.92), P < 0.00001], and diabetes mellitus[OR = 1.18, 95% CI (1.01, 1.37), P = 0.03 < 0.05], and the uncertain factors were donor type [OR = 4.10, 95% CI (0.28, 59.79), P = 0.30 > 0.05], time of transplantation [OR = 0.95, 95% CI (0.78, 1.16), P = 0.64 > 0.05], and the use of cyclosporine [OR = 1.50, 95% CI (0.62, 3.64), P = 0.37 > 0.05].

CONCLUSION

There are many factors influencing CMV infection and disease in kidney transplant patients. Risk factors should be carefully monitored, protective factors strengthened, and more attention paid to uncertain factors.