Five-year single-center analysis of cytomegalovirus viremia in kidney transplant recipients and possible implication for novel prophylactic therapy approaches

BackgroundCytomegalovirus (CMV) infections are a common complication after kidney transplantation (KTx) and negatively affecting patient outcome. Valganciclovir (VGC) prophylaxis is often limited by drug-induced side effects and dose reduction due to decline in kidney function.MethodIn the present study, episodes of CMV viremia in the first year after KTx in a cohort of 316 recipients were analyzed retrospectively to identify risk factors linked to persistent infections.ResultsIn the studied cohort, 18.7% of patients showed a high-risk (HR) constellation (D+/R-) for CMV infections. CMV viremia affected 22% of our cohort, with HR patients being the most affected cohort (44.1%). Within this group, most viremic events (65.3%) occurred while patients were still on prophylactic therapy, showing significantly higher viral loads and a longer duration compared to seropositive recipients.ConclusionThe analysis at hand revealed that detection of viremia under ongoing antiviral prophylaxis bears an increased risk for sustained viral replication and antiviral drug resistance in HR patients. We identified low estimated glomerular filtration rate (eGFR) and lower dose VGC prophylaxis post-KTx as a risk factor for breakthrough infections in HR patients in our single center cohort. These patients might benefit from a closer CMV monitoring or novel prophylactic agents as letermovir.image In this single-center study, high-risk patients are at risk for prolonged and breakthrough cytomegalovirus infections. Most breakthrough infections appear under substantial valganciclovir prophylactic dose reduction and low estimated glomerular filtration rate.image