Respiratory infections complicate lung transplantation and increase the risk of allograft dysfunction. Allograft lungs may have different susceptibilities to infection than native lungs, potentially leading to different disease severity in lungs of single lung transplant recipients (SLTRs).


To study whether infections affect allograft and native lungs differently in SLTRs but similarly in double LTRs (DLTRs).


Using an institutional database of LTRs, medical records were searched, chest computed tomography studies were systematically reviewed, and histopathologic features were recorded per lung lobe and graded semiquantitatively. A multilobar-histopathology score (MLHS) including histopathologic data from each lung and a bilateral ratio (MLHSratio) comparing histopathologies between both lungs were calculated in SLTRs and compared to DLTRs.


Six SLTRs died of infection involving the lungs. All allografts showed multifocal histopathologic evidence of infection, but at least 1 lobe of the native lung was uninvolved. In all 5 DLTRs except 1, histopathologic evidence of infection was seen in all lung lobes. On computed tomography, multifocal ground-glass and/or nodular opacities were found in a bilateral distribution in all DLTRs but in only 2 of 6 SLTRs. In SLTRs, the MLHSAllograft was higher than MLHSNative (P = .02). The MLHSratio values of SLTR and DLTR were significantly different (P < .001).


Allograft and native lungs appear to harbor different susceptibilities to infections. The results are important for the management of LTRs.

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Author notes

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Villalba is currently with the Infectious Diseases Pathology Branch, Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases, at the Centers for Disease Control and Prevention, Atlanta, Georgia. Villalba and Cheek-Norgan contributed equally to this study.

Competing Interests

Roden received honoraria from up-to-date and the Pathology Learning Center, is consultant to Bristol Myers Squibb, and serves on the advisory board of Sanofi Oncology. The other authors have no relevant financial interest in the products or companies described in this article.

Previously presented as abstract at the 12th Pulmonary Pathology Society Biennial Meeting; June 25-27, 2022; Cork, Ireland.

Supplementary data