Pre-Emptive Therapy for the Treatment of Cytomegalovirus After Kidney Transplantation

Molecular monitoring of viral infections in immunocompromised patients in a large university hospital in Italy: reflections after thirteen years of real-life activity

PURPOSE

This study aimed to investigate the prevalence and viral reactivations of clinical interest in the immunocompromised patient with particular focus on hematologic and solid organ transplant recipients.

METHODS

Molecular screening data of CMV, EBV, JCV and BKV from 2011 to 2023 were analyzed. This extensive time span allowed the access to more than 100,000 samples from over 20,000 patients treated at Policlinico Umberto I. It was possible to temporally investigate patient attendance patterns, average age distribution, seasonality of infections, and positivity rates of the analyzed viruses.

RESULTS

Between 2019 and 2022 a significant reduction in organ transplants performed and in the positive molecular detection of EBV, JCV and BKV was observed. Additionally, there has been a noteworthy decrease in CMV reactivations, with a reduction of up to 50% starting in 2019. A remarkable reduction of 39% in the rate of CMV viral reactivation has been also achieved in SOT between 2016 and 2023.

CONCLUSION

The years following 2019 were profoundly impacted by the COVID-19 pandemic era. This period resulted in a substantial reduction in healthcare services and hospital visits. Furthermore, the introduction of the drug Letermovir in Italy in 2019 demonstrated remarkable efficacy, evidenced by a reduction in CMV reactivations. Additionally, the adoption of a novel clinical approach centered on personalized therapy facilitated improved management of immunocompromised patients.

Significant Increase in Cytomegalovirus (CMV) Infection in Solid Organ Transplants Associated With Increased Use of Thymoglobulin as Induction Therapy?

BACKGROUND

Cytomegalovirus (CMV) infection remains one of the most common viral pathogens affecting solid organ transplants (SOT). In 10 years of following the outcome of transplants, we noticed an increased incidence of CMV infection, along with increased use of rabbit anti-thymocyte globulin (rATG). The study aims to assess the incidence of active CMV infection and disease, response to treatment, and recurrence in a cohort of SOT. Furthermore, we look for correlating the CMV incidence with the type of induction therapy: r-ATG or interleukin 2 receptor-blocking antibody (basiliximab).

METHODS

This was a single-center, retrospective 10-year study in patients submitted to kidney, kidney-liver, and kidney-pancreas transplants who used a preemptive therapy protocol for CMV.

RESULTS

Among the 476 enrolled transplant recipients, 306 (64.2 %) had at least one episode of CMV infection (replication), and 71/306 patients (23.2 %) presented CMV-related disease. The most frequent clinical conditions associated with CMV disease were gastrointestinal. Among the 476 transplant patients, 333 received immunosuppressive induction with rATG (69.9 %); 140 (29.4 %) received induction with interleukin 2 receptor-blocking antibody (basiliximab). The initial maintenance immunosuppressive therapy in the patients who presented CMV infection was primarily performed with prednisone, tacrolimus, and sodium mycophenolate (91.7 %). The induction with rATG increased from 35.2%-94.6% in 10 years. The incidence of CMV infection was 20.7 % in the first year of observation and gradually increased to 87.3 % in the last year.

CONCLUSIONS

The data suggest that the increase in the use of rATG in recent years could be responsible for the very expressive increase in the incidence of CMV infection/disease.

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.