Assessment of Quantiferon®-CMV and Immuknow® Assays in CMV-seropositive Lung Transplant Recipients to Stratify Risk of CMV Infection.

Abstract

Lung transplant recipients (LTR) are at significantly higher risk for cytomegalovirus (CMV) infection compared to recipients of other solid organ transplants (SOT), with both the direct and indirect effects of CMV infection contributing to increased morbidity and mortality in this population. Current guidelines recommend universal antiviral prophylaxis for a duration of 6 to 12 months depending on the recipient’s CMV serostatus. However, prolonged antiviral use is associated with adverse effects, often necessitating early discontinuation of prophylaxis. To address this, several authors have proposed the use of the Quantiferon®-CMV assay as a tool to stratify the risk of CMV disease in SOT recipients, which could facilitate more personalized prophylaxis strategies. Nevertheless, its utility in CMV-seropositive lung transplant recipients (LTR+), who represent 80–90% of LTRs in Spain, remains unclear. Notably, it has been reported that up to 20% of LTR+ patients with high Quantiferon®-CMV responses still develop CMV infection. A potential explanation for this paradox is that high levels of immunosuppression may suppress other critical immune pathways involved in CMV control. The overall intensity of immunosuppression can be evaluated using the Immuknow® assay. Based on this, we hypothesized that the risk of CMV infection in LTR+ patients could be more accurately stratified by combining results from both the Quantiferon®-CMV and Immuknow® assays.