The usefulness of transbronchial lung cryobiopsy for chronic lung allograft dysfunction: A case report.

A 27-year-old man underwent bilateral lung transplantation for bronchiolitis obliterans. Within eight months of lung transplantation, he developed recurrent fever, lung shadows, and elevated inflammatory markers three times. Although high-resolution computed tomography suggested infectious disease, antibiotic therapy did not improve his condition. Steroid pulse therapy temporarily improved his condition, but the same symptoms recurred when the steroids were reduced. Transbronchial lung cryobiopsy (TBLC) revealed bronchiolar fibrotic obstruction with inflammation, supporting the diagnosis of chronic lung allograft dysfunction. Although patient selection remains key due to procedural risks, TBLC may be useful in distinguishing between infection and rejection in lung transplant recipients.