Serendipity on surveillance: an unusual transbronchial biopsy finding in a lung transplant recipient

Flexible bronchoscopy is routinely utilized to monitor allograft function after lung transplantation (LT). While transbronchial lung biopsy (TBLB) is valuable as it permits direct histological assessment of the allograft, unexpected findings are occasionally encountered. We report a 72-year-old male with advanced chronic obstructive pulmonary disease who underwent a right single LT. His early posttransplant course was uneventful, and he presented for 6-week surveillance bronchoscopy. Although TBLB of the right lower lobe showed no evidence of rejection, one section revealed a small blood vessel with an organized intravascular thrombus. This prompted hospital admission, and an acute segmental pulmonary embolus was confirmed. Further workup identified acute deep vein thrombosis of the right soleal vein, likely the source of the embolism. The patient was treated with standard anticoagulation and discharged without complications. He was doing well at the 3-month follow-up. This case highlights the high incidence of venous thromboembolism among LT recipients and the unique challenges specific to this population. We emphasize the importance of following through on unexpected findings on TBLB, which may facilitate the timely diagnosis of posttransplant complications.