Since February 21 2020, when the Italian National Institute of Health (Istituto Superiore di Sanità–ISS) reported the first autochthonous case of infection, a dedicated surveillance system for SARS‐CoV‐2‐positive (COVID+) cases has been created in Italy. These data were cross‐referenced with those inside the Information Transplant System in order to assess the cumulative incidence (CI) and the outcome of SARS‐COV‐2 infection in solid organ transplant recipients (SOTRs) who are assumed to be most at risk. We compared our results with those of COVID+ nontransplanted patients (Non‐SOTRs) with follow‐up through September 30, 2020. The CI of SARS‐CoV‐2 infection in SOTRs was 1.02%, higher than in COVID+ Non‐SOTRs (0.4%, p < .05) with a greater risk in the Lombardy region (2.89%). The CI by type of organ transplant was higher for heart (CI 1.57%, incidence rate ratio [IRR] 1.36) and lower for liver (CI 0.63%, IRR 0.54). The 60‐day CI of mortality was 30.6%, twice as much that of COVID+ Non‐SOTRs (15.4%) with a 60‐day gender and age adjusted odds ratio (adjusted‐OR) of 3.83 for COVID+ SOTRs (95% confidence interval [3.03–4.85]). The lowest 60‐day adjusted‐OR was observed in liver SOTRs (OR 0.46, 95% confidence interval [0.25–0.86]). More detailed studies on disease management and evolution will be necessary in these patients at greater risk of COVID‐19.

Background. SARS-CoV-2 infection is heterogeneous in clinical presentation and disease evolution. To investigate whether immune response to the virus can be influenced by genetic factors, we compared HLA and AB0 frequencies in organ transplant recipients and waitlisted patients according to presence or absence of SARS-CoV-2 infection. Methods.A retrospective analysis was performed on an Italian cohort composed by transplanted and waitlisted patients in a January 2002 to March 2020 time frame. Data from this cohort were merged with the Italian registry of COVID + subjects, evaluating infection status of transplanted and waitlisted patients. A total of 56 304 cases were studied with the aim of comparing HLA and AB0 frequencies according to the presence (n = 265, COVID + ) or absence (n = 56 039, COVID -) of SARS-CoV-2 infection. Results. The cumulative incidence rate of COVID-19 was 0.112% in the Italian population and 0.462% in waitlisted/ transplanted patients (OR = 4.2; 95% CI, 3.7-4.7; P < 0.0001). HLA-DRB1*08 was more frequent in COVID + (9.7% and 5.2%: OR = 1.9, 95% CI, 1.2-3.1; P = 0.003; P c = 0.036). In COVID + patients, HLA-DRB1*08 was correlated to mortality (6.9% in living versus 17.5% in deceased: OR = 2.9, 95% CI, 1.15-7.21; P = 0.023). Peptide binding prediction analyses showed that these DRB1*08 alleles were unable to bind any of the viral peptides with high affinity. Finally, blood group A was more frequent in COVID + (45.5%) than COVIDpatients (39.0%; OR = 1.3; 95% CI, 1.02-1.66; P = 0.03). Conclusions. Although preliminary, these results suggest that HLA antigens may influence SARS-CoV-2 infection and clinical evolution of COVID-19 and confirm that blood group A individuals are at greater risk of infection, providing clues on the spread of the disease and indications about infection prognosis and vaccination strategies.

Organ transplantation, e.g., of the heart, liver, or kidney, is nowadays a routine strategy to counteract several lethal human pathologies. From literature data and from data obtained in Italy, a striking scenario appears well evident: women are more often donors than recipients. On the other hand, recipients of organs are mainly males, probably reflecting a gender bias in the incidence of transplant-related pathologies. The impact of sex mismatch on transplant outcome remains debated, even though donor-recipient sex mismatch, due to biological matters, appears undesirable in female recipients. In our opinion, the analysis of how sex and gender can interact and affect grafting success could represent a mandatory task for the management of organ transplantation.

Angelico and Trapani contributed equally for first authorship.

This study showed a low risk of donor-recipient CPE transmission, indicating that donor CPE colonization does not necessarily represent a contraindication for donation unless colonization regards the organ to be transplanted. Donor and recipient screening remains essential to prevent CPE transmission and cross-infection in transplantation centres.