Ian Kracalik, Pallavi Annambhotla, David W. McCormick, Andrew I. Geller, Kelsey McDavid, Isabel Griffin, Raymond Lynch, Brianna Doby, Yoichiro Natori, Sofya Tokman, Christine M. Durand, Camille N. Kotton, Emily Blumberg, Ricardo M. La Hoz, Lauri Hicks, Stephanie M. Pouch, Sridhar V. Basavaraju, Donor-Derived KSHV Investigation Group, Donor-Derived KSHV Investigation Group, Adam Bregman, Costi D. Sifri, Megan Del Vecchio, Amir Emtiazjoo, Ghady Haidar, Kenneth T. Hughes, Nicholas Marschalk, Rachel A. Miller, Swati Rao, Mary Saputo, Benjamin Keebler, Darryl Nethercot, Matthew Niles, Patricia Carroll, Kerri Jones
Kaposi sarcoma-associated herpesvirus (KSHV) infection is the cause of Kaposi sarcoma (KS), certain lymphoproliferative disorders, and the inflammatory condition Kaposi sarcoma-associated herpesvirus inflammatory cytokine syndrome (KICS). In solid organ transplant recipients, KSHV-related complications can result from reactivation of latent infection, new posttransplant infection, or transmission of virus from the transplanted organ. However, testing of donors and recipients is not routinely performed. During January 2021-September 2025, after transplantation of 185 organs into 153 recipients, 46 deceased donors were identified whose transplanted organs were suspected of having transmitted KSHV, approximately five times the number of such donors (nine) reported during 2016-2020. As of February 2026, a posttransplantation KSHV infection has been identified among 74 (48%) of these 153 transplant recipients. Among the 74 recipients with KSHV infection, 45 (61%) developed KS; 10 (14%) of these recipients with KS also developed a lymphoproliferative disorder (multicentric Castleman disease [eight], posttransplant lymphoproliferative disorder [one], and primary effusion lymphoma [one]) and six (8%) developed KICS; four (5%) recipients developed a lymphoproliferative disorder alone (primary effusion lymphoma [one] and posttransplant lymphoproliferative disorder [three]); and one (1%) developed KICS alone. To date, 25 (16%) of the 153 transplant recipients have died. Most donors and recipients were HIV-negative, and nonmedical drug use was common among donors. Clinicians should maintain a high index of suspicion for KSHV in transplant recipients, particularly when donors have risk factors including nonmedical drug use, or when another recipient from the same donor is found to be infected. Development and implementation of effective testing strategies and timely reporting could guide clinical management, reduce risk for KSHV-related complications, and improve transplant safety.