Donors Infectious Risk Stratification: Activity of the Italian National Transplant Center

Background: The use of organs from donors at increased infectious risk represents an effort to broaden the donor pool, but case-by-case evaluation may be needed. The Italian National Transplant Center (CNT) is supported by a second opinion task force of experts consulted for donors with complicated infectious assessment. Methods: Retrospective observational study to describe infectious disease second opinion (IDSO) activity between June 2022 and October 2023. We analyzed the distribution of the infectious risk level, assigned according to the CNT protocol in five categories. Results: IDSO evaluation was requested for 1246 of the 4153 (30%) of the donors. The mean age was 58.2 years, 56.8% were male, and most of them were Italians (91%). Donors had on average 1.5 (SD 0.9, range 1–6) infectious problems, the most frequent being pneumonia (453, 36.4%), inflammatory marker elevation (299, 24%), and bacteremia (125, 10%). The infectious risk was classified in most cases as increased but acceptable risk (60.8%), followed by negligible risk (19.2%) and increased but acceptable risk only for critical recipients (12.4%). Only 5.2% of donors were unacceptable, the main reason being inappropriately treated multidrug-resistant organism bacteremia or candidemia (21/65, 32.3%). Lung was the most frequently excluded organ (18.2%). In 284 donors (24%), additional testing was recommended, and in 299 recipients (25.3%), a specific therapeutic indication was given. Conclusions: IDSO activity allowed the acceptance of the donor pool in almost 95% of the reviewed cases. Prospective international studies are necessary to understand the real impact of donors at increased infectious risk on recipient outcomes.