Diagnostic alignment to optimize inter-rater reliability among lung transplant pathologists.

Area of Science:

• Pulmonary Medicine
• Transplant Pathology
• Histopathology

Background:

• Inter-pathologist agreement in lung transplant (LTx) rejection assessment is often poor.
• Acute lung injury (ALI) and organizing pneumonia (OP) are newly identified risk factors for chronic lung allograft dysfunction (CLAD), alongside acute rejection (AR) and lymphocytic bronchiolitis (LB).
• Improving inter-rater reliability (IRR) for these histopathologic findings is crucial for patient management and clinical trial design.

Purpose of the Study:

• To assess and improve inter-rater reliability (IRR) among lung transplant pathologists for identifying histopathologic risk factors of CLAD.
• To establish standardized diagnostic criteria for high-risk histopathology in lung allografts.

Main Methods:

• Nine pathologists from eight North American LTx centers participated in the study.
• Diagnostic alignment sessions were conducted to discuss histomorphologic features of CLAD high-risk pathology.
• Pathologists blindly scored 75 digitized slides, and Fleiss' kappa was used to calculate IRR for individual findings and any high-risk finding.

Main Results:

• Good IRR was achieved for identifying any high-risk finding (k=0.578, 78.9% agreement).
• Individual findings showed moderate to good IRR: AR (k=0.582, 79.1%), LB (k=0.683, 83.5%), ALI (k=0.418, 70.9%), and OP (k=0.621, 81.0%).

Conclusions:

• Multicenter lung transplant pathologists achieved good IRR in identifying histopathology associated with CLAD after diagnostic alignment.
• Standardized assessment of these histopathologic risk factors can enhance diagnostic consistency in lung transplantation.