Lung long distance: histopathological changes in lung tissue after COVID-19 pneumonia

Scientific paper - Original scientific paper

• Author: Grgur Salai
• Author: Jasna Tekavec-Trkanjec
• Author: Ivona Kovačević
• Author: Čedna Tomasović-Lončarić
• Author: Arijana Pačić
• Author: Mirna Vergles
• Author: Đivo Ljubičić
• Author: Daria Cvetković-Kučić
• Author: Ivica Lukšić
• Author: Bruno Baršić
• Author's institution: University of Zagreb; School of Medicine; (Department of Infectious Diseases)
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences; Infectology

Abstract (english)

Aim: To investigate histopathological changes in the lung tissue of long-COVID patients.

Methods: In this cross-sectional study, transbronchial lung biopsy was performed in long-COVID patients with persisting symptoms and radiological abnormalities. Histopathologic analyses were performed by using hematoxylin-eosin, Martius, Scarlet and Blue, Movat's, thyroid transcription factor 1, CD34, and CD68 staining.

Results: Adequate biopsy samples were obtained from 29/32 patients. The median (Q1-Q3) time from disease onset to biopsy was 13 (9-20) weeks. We observed several histopathologic patterns: DAD with vascular abnormalities (VA) (n=8); VA with inflammatory pattern (n=4); inflammatory pattern (n=13), and fibrotic pattern (n=4). VA included capillary thrombi, dilated venules, and dissection of small pulmonary arteries. DAD with VA was detected up to the 9th week from the onset of disease; inflammatory pattern from the 8th to 28th week (4 patients with this pattern biopsied in the 11th-13th week had accompanying VA); and a predominantly fibrotic pattern was found at weeks 8, 10, 48, and 49.

Conclusion: Our study observed a slow recovery of lung tissue with long-lasting DAD and VA, likely followed by interstitial inflammation or focal fibrosis. These findings might be the underlying cause of the slow recovery of long-COVID patients.

• Keywords (english): Adult; Aged; Biopsy; COVID-19 / complications; COVID-19 / pathology; Cross-Sectional Studies; Female; Humans; Lung / pathology; Male; Middle Aged; SARS-CoV-2
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review
• Publication version: Published version
• Journal title: Croatian Medical Journal
• Numbering: vol. 65, no. 6, pp. 501-509
• p-ISSN: 0353-9504
• e-ISSN: 1332-8166
• DOI: https://doi.org/10.3325/cmj.2024.65.501
• URN:NBN: urn:nbn:hr:105:574975
• Publication: 2024-12-30
• Document URL: https://www.cmj.hr/2024/65/6/39812099.htm
• Type of resource: Text
• Access conditions: Open access
• Created on: 2025-01-24 12:40:42