Spectrum of chronic lung allograft dysfunction pathology in human lung transplantation.
J Heart Lung Transplant
; 2024 Apr 23.
Article
in En
| MEDLINE
| ID: mdl-38663465
ABSTRACT
BACKGROUND:
Long-term survival after lung transplantation (LTx) remains limited by chronic lung allograft dysfunction (CLAD), which includes 2 main phenotypes bronchiolitis obliterans syndrome (BOS) and restrictive allograft syndrome (RAS), with possible overlap. We aimed to detail and quantify pathological features of these CLAD sub-types.METHODS:
Peripheral and central paraffin-embedded explanted lung samples were obtained from 20 consecutive patients undergoing a second LTx for CLAD, from 3 lobes. Thirteen lung samples, collected from non-transplant lobectomies or donor lungs, were used as controls. Blinded semi-quantitative grading was performed to assess airway fibrotic changes, parenchymal and pleural fibrosis, and epithelial and vascular abnormalities.RESULTS:
CLAD lung samples had higher scores for all airway- and lung-related parameters compared to controls. There was a notable overlap in histologic scores between BOS and RAS, with a wide range of scores in both conditions. Parenchymal and vascular fibrosis scores were significantly higher in RAS compared to BOS (p = 0.003 for both). We observed a significant positive correlation between the degree of inflammation around each airway, the severity of epithelial changes, and airway fibrosis. Immunofluorescence staining demonstrated a trend toward a lower frequency of club cells in CLAD and a higher frequency of apoptotic club cells in BOS samples (p = 0.01).CONCLUSIONS:
CLAD is a spectrum of airway, parenchymal, and pleural fibrosis, as well as epithelial, vascular, and inflammatory pathologic changes, where BOS and RAS overlap significantly. Our semi-quantitative grading score showed a generally high inter-reader reliability and may be useful for future CLAD histologic assessments.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
J Heart Lung Transplant
Journal subject:
CARDIOLOGIA
/
TRANSPLANTE
Year:
2024
Type:
Article