Valganciclovir is not a risk factor of BK polyomavirus viremia

Is Polyomavirus-Associated Nephropathy More Common in Kidney Transplant Recipients Exposed to Valganciclovir? A Retrospective Single Center Analysis

BACKGROUND

BK polyomavirus-associated nephropathy (PVAN) is a frequent complication in the early phase after kidney transplantation. The most important risk factor for PVAN is the intensity of immunosuppression. A recent study suggests that exposure to valganciclovir (VGC) could also be a risk factor.

METHODS

We performed a retrospective, single-center study to investigate the effect of valganciclovir exposure on the risk for PVAN during the first 100 days post transplant. Cytomegalovirus (CMV) seronegative recipients of a CMV seropositive donor kidney received VGC prophylaxis, whereas CMV seropositive recipients were managed by a pre-emptive CMV strategy. Cox regression analysis was used to identify risk factors for PVAN development with VGC treatment and strength of immunosuppressive therapy as time-dependent variables.

RESULTS

A total of 211 adults who received a kidney transplant between 2014 and 2019 were included. Eighteen (9%) developed PVAN. Multivariate regression analysis showed that women have a lower risk of developing PVAN (hazard ratio [HR] 0.08 (confidence interval [CI] 0.01-0.58), P = .013), whereas age was associated with an increased risk for PVAN (HR 1.04 for every additional year [CI 1.00-1.08], P = .029). There was a trend toward a lower risk of PVAN for patients on reduced immunosuppressive therapy (HR 0.44 [CI 0.15-1.24], P = .12). VGC use was not associated with the risk for PVAN (HR 0.99 [CI 0.35-2.78], P = .98).

CONCLUSIONS

In our study, VGC exposure was not associated with the risk for PVAN. Our study is the first to reassess in depth the hypothesis that VGC treatment increases the risk of PVAN. The unique strength of this study is the correction for the degree of immunosuppression and the statistical use of time-dependent covariates. This methodological approach can provide a foundation for further studies needed to confirm our findings.

CMV infection, valganciclovir exposure, and the risk of BK viremia and associated nephropathy after kidney transplantation: Is there a link?

BACKGROUND

Immunomodulatory effects attributable to cytomegalovirus (CMV) would predispose to BK polyomavirus (BKPyV) infection after kidney transplantation (KT), although available evidence is conflicting. It has been suggested that (val)ganciclovir therapy may increase the risk of BKPyV viremia and BKPyV-associated nephropathy (BKPyVAN) as a result of drug-induced T-cell impairment.

METHODS

We investigated whether CMV replication and/or (val)ganciclovir exposure (either as prophylaxis or treatment) were associated with the development of BKPyV viremia or BKPyVAN in a prospective cohort of 399 KT recipients. CMV infection (any level or high-level viremia and area under the curve of DNAemia) and (val)ganciclovir exposure (any duration of therapy and cumulative days of treatment) during the first post-transplant year were explored through separate landmark survival analyses.

RESULTS

Cumulative incidence of BKPyV viremia and BKPyVAN after a median follow-up of 551 days was 23.1% and 2.5%, respectively. One-year rates of CMV infection and (val)ganciclovir therapy were 47.4% and 54.1%, respectively. No differences were observed in BKPyV viremia- or BKPyVAN-free survival according to previous CMV infection or (val)ganciclovir exposure in any of the landmark analyses. Adjusted Cox models confirmed this lack of association.

CONCLUSION

Our findings do not confirm the existence of a relevant impact of CMV infection or (val)ganciclovir therapy on the risk of post-transplant BKPyV events.

Trichodysplasia spinulosa: a comprehensive review of the disease and its treatment

Trichodysplasia spinulosa (TS) is a rare dermatological disease caused by TS‐associated polyomavirus (TSPyV) in immunosuppressed patients. The seroprevalence of TSPyV in immunocompetent adults is high and the number of immunosuppressed patients developing TS remains low, suggesting that TS is underdiagnosed and/or that additional unknown factors are needed in order to develop TS. There is no well‐established treatment for TS, and to date a majority of reported cases have consequently received ineffective therapies, likely due to the unavailability of reviews and recommendations of treatments for TS. The few treatments reported in case reports to be effective include topical cidofovir 3%, reduction of immunosuppression and oral valganciclovir. In this comprehensive review, we present all published cases to date, together with a summary of all treatments for TS categorized by overall clinical efficacy, thus addressing this rare disease and what appears to be its clinically efficacious treatment.

Clinical features of BK-polyomavirus and cytomegalovirus co-infection after kidney transplantation

BK polyomavirus (BKPyV) and cytomegalovirus (CMV) are the main viral pathogens affecting the graft and recipient outcome after allogenic kidney transplantation. It has recently been found that infection with both viruses has a greater impact on kidney graft function than a single infection. We retrospectively analyzed a cohort of 723 recipients who received kidney transplantation between 2007 and 2015 after living and postmortal donation for differences in risk and outcome parameters regarding BKPyV (DNAemia) and CMV (CMV DNAemia) co-infection compared to sole viremias and to patients without viremia. Of all kidney allograft recipients in our cohort, 8.2% developed co-infection with BKPyV DNAemia and CMV DNAemia, 15.1% showed BKPyV viremia alone and 25.2% sole CMV DNAemia. Acute rejection was closely linked with co-infection (multivariable analysis, p = 0.001). Despite the fact that the estimated glomerular filtration rate of patients with co-infection was noticeably reduced compared to patients with BKV or CMV infection alone, transplant survival and patient survival were not significantly reduced. Co-infection with BKPyV and CMV in kidney transplanted patients is significantly associated with inferior allograft function. Since co-infection is strongly associated with acute rejection, co-infected individuals should be considered a risk collective.

Cytomegalovirus Viremia after Living and Deceased Donation in Kidney Transplantation

Despite screening, effective anti-viral drugs and risk-balanced prophylaxis, cytomegalovirus (CMV) remains a major cause of morbidity in transplant patients. The objective of this study was to retrospectively analyze the risk factors associated with CMV viremia after kidney transplantation in a large European cohort with standardized valganciclovir prophylaxis in the present era. A special focus was placed on the comparison of living and postmortal donation. We conducted a longitudinal observational study involving 723 adult patients with a total of 3292 patient-years who were transplanted at our center between 2007 and 2015. Valganciclovir prophylaxis was administered over 100 days for CMV+ donors (D) or recipients (R), over 200 days for D+/R−, and none in D−/R−. A CMV+ donor, rejection episodes, and deceased donor transplantation were identified to be associated with increased incidences of CMV viremia. Although we did not find a reduced overall survival rate for patients with CMV viremia, it was associated with worse graft function. Since we observed a relevant number of CMV infections despite prescribing valganciclovir prophylaxis, a pre-emptive strategy in patients with (suspected) adherence restrictions could be favored. Our data can help transplant physicians educate their patients about their individual CMV risk and choose the most appropriate CMV treatment approach.