Donor Cytomegalovirus Transmission Patterns in Solid Organ Transplant Recipients With Primary Infection

Abstract Background The epidemiology of single versus multiple cytomegalovirus (CMV) strain transmission from donor (D+) to seronegative solid organ transplant (SOT) recipients (R−) is uncertain, as is whether “relapsing” recipient infection represents changing strain predominance when multiple strains are transmitted. Here we characterized CMV strain transmission patterns in D+/R− SOT recipients. Methods We studied pairs or groups of D+/R− SOT recipients who received organs from a common donor (group A) and recipients who experienced ≥2 waves of CMV DNAemia (group B). CMV in plasma was characterized by genotype-specific real-time PCR for genes gB and gH. Results Single concordant genotypes were identified in 12 of 18 recipient pairs/group sharing a common donor (group A); at least 6 of 18 (33%) donors transmitted > 1 strain. A single CMV strain was detected in 14 of 15 recipients in group B; only 1 recipient had coinfection. A shift in CMV strain predominance occurred after the first posttransplant year in at least 4 recipients with coinfection. Conclusions Using a common donor approach, we confirmed that multiple CMV strain transmission from donors to R− SOT recipients is not uncommon. D+/R− SOT recipients with CMV coinfection can undergo changes in strain predominance in late waves of CMV DNAemia. Although multiple strain transmission by SOT donors is not uncommon, most D+/R− recipient recurrent CMV DNAemia was due to infection with the same single strain. In coinfected recipients, late CMV DNAemia waves frequently demonstrated CMV strain predominance shifts