Cytological monitoring of peripheral blood, bronchoalveolar lavage fluid, and transbronchial biopsy specimens during acute rejection and cytomegalovirus infection in lung and heart-lung allograft recipients

Study objectives: Acute rejection and cytomegalovirus (CMV) infection are i mportant complications after lung and heart-lung transplantation. We sought to investigate whether acute rejection and CMV infection demonstrated as C MV antigenemia had an effect on the cell profiles of peripheral blood (PB), bronchoalveolar lavage fluid (BAL-F), or TBB histology. Patients and design: In this prospective study, composition of cells in PB, BAL-F, and TBB samples from 20 lung or heart-lung transplantation patients were analyzed during episodes of acute rejection or CMV antigenemia, Rejec tion was graded according to the International Society for Heart and Lung T ransplantation criteria. As controls, samples with no evidence of rejection or infection were used. To evaluate the effect of time on cellular finding s, samples were divided into three groups according to time after transplan tation: 1-30, 31-180, and more than 180 d after transplantation. Results: Acute rejection was associated with mild blood basophilia (p < 0.0 5; specificity 94%, sensitivity 42%). In BAL-F during rejection, the number of basophils (p ( 0.05), eosinophils (p < 0.05), and lymphocytes (p < 0.05 ; specificity 77%, sensitivity 64%) was increased compared to controls duri ng the post-operative month 1. Later-occurring rejections were associated w ith increased amounts of neutrophils in BAL-F (p < 0.05; specificity 82%, s ensitivity 74%). In TBB histology, acute rejections were associated with pe rivascular and/or peribronchial infiltration of lymphocytes (p < 0.001) and plasma cells (p ( 0.05) compared to controls. In our patients receiving ga ncyclovir prophylaxis, CMV antigenemia did not significantly alter the cell profiles in PB and BAL-F nor the inflammatory cell picture in TBB histolog y. Conclusion: TBB histology remains the 'gold standard' for diagnosing reject ion in lung and heart-lung transplantation patients, as the inflammatory ce ll findings in TBB specimens are highly specific for rejection. The cellula r changes associated with rejection, mild PB basophilia and increased propo rtions of lymphocytes in early- and neutrophils in later-occurring rejectio n, observed in BAL-F cannot be considered specific for rejection, but may w arrant clinical suspicion of rejection.