Background: Cytomegalovirus (CMV) is the most important opportunistic pathogen after solid organ transplantation (SOT). For CMV seronegative recipients, the risk of CMV infection transmitted from seropositive donors is up to 50%. The ability of the donors graft to transmit CMV has been scarcely studied.
Methods: A retrospective study (2000-2011) was performed to assess CMV IgG seroconversion in high-risk (CMV D+/R-) adult and pediatric recipients of solid organ transplantation at the University of Alberta Hospital and Stollery Childrens Hospital in Edmonton.
Results: Out of 409 high risk patients, 284 patients (69%) seroconverted for CMV during follow-up (median 369 days, IQR 205-811) and 65% at two years (Figure 1). Almost 70% of patients who seroconverted (198/284) had a positive CMV DNAemia before or 30 days after the first detectable CMV Ig G. The stratified allograft, different rates of seroconversion at 2 years follow-up were observed, with the highest observed for lung and liver transplant recipients (78.6% and 68% respectively); 54% for kidneys and heart patients had the lowest rate (46%) (p=0.004). Analyzing donors who donated to at least 2 seronegative recipients, 65 donors donated graft to 151 recipients. Fifteen recipients were excluded from this analysis because inadequate follow-up, 57 donors and 128 recipients were therefore analyzed. At 2 years of follow-up, 9 out of 57 donors (16%) did not transmit CMV to any recipient (7 Hearts, 5 Kidneys, 4 Lungs, 3 Livers and 2 others; 2.3 recipients per donor), 21 donors transmitted CMV inconsistently to their different recipients (4/6 hearts, 10/14 lungs, 4/13 kidney, 6/12 liver, 1/4 other) and 27 donors transmitted CMV to all recipients (3 hearts, 11 lungs, 19 kidneys, 18 liver, 6 other).
Conclusion: At two years post-transplant, 35% of high-risk recipients did not seroconvert for CMV. The risk of transmission was different among allografts, being higher for lung transplant recipients. Despite recipient characteristics, some donors were less likely to transmit CMV and in up to 16% of donors there was no CMV transmission at two years post-transplant.
C. Mabilangan, None
J. Preiksaitis, None