Logical versus absolute lymphocyte count–guided preemptive therapy for cytomegalovirus prevention in kidney transplant recipients: a randomized controlled trial

Abstract

Objectives A preemptive approach using plasma cytomegalovirus (CMV) DNA load monitoring is recommended for CMV-seropositive solid organ transplant recipients. However, limited access to CMV quantitative nucleic acid amplification testing poses challenges in resource-constrained settings. We hypothesized that absolute lymphocyte count (ALC)-guided monitoring could provide an effective alternative strategy. Methods We conducted an open-label, randomized controlled trial at a single transplant center in Thailand (February-November 2023). Adult CMV-seropositive kidney transplant (KT) recipients who did not receive anti-thymocyte globulin induction were randomized in a 1:1 ratio to either the logical (LOG) group, defined as routine plasma CMV quantitative nucleic acid amplification testing performed every 4 weeks for 12 weeks, or the ALC group, which underwent testing only when the ALC was <1000 cells/mm³. Participants were followed for 6 months after transplantation to compare CMV infection rates and testing costs. Results A total of 98 KT recipients were enrolled (49 per group; mean ± SD age, 46 ± 11 years; 66.3% male). Baseline demographic characteristics were comparable between groups. Overall, 25 participants (25.5%) developed CMV infection within 6 months after KT. CMV infection occurred in 13 participants (26.5%) in the LOG group and 12 participants (24.5%) in the ALC group (P = 0.817). No significant differences were observed between groups in the rates of CMV DNAemia, CMV disease, anti-CMV therapy, or mortality (all P >0.05). The total cost of plasma CMV DNA load testing was significantly lower in the ALC group than in the LOG group ($2320 vs $10,014; P = 0.002). Conclusions ALC-guided monitoring could demonstrate effectiveness comparable to that of routine CMV DNA surveillance for CMV infection prevention in KT recipients. Given its simplicity and availability, ALC may serve as a feasible and cost-efficient adjunct for guiding preemptive therapy in low- to moderate-risk solid organ transplant recipients.