Lung
Infectious
Viral
SARS
Author: Elliot Weisenberg, M.D.
Last author update: 1 September 2011
Last staff update: 30 December 2020
Copyright: 2003-2024, PathologyOutlines.com, Inc.
PubMed search: SARS [title] pulmonary
Table of Contents
Clinical features | Microscopic (histologic) description | Positive stains | Additional referencesCite this page: Weisenberg E. SARS. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/lungnontumorSARS.html. Accessed April 24th, 2024.
Clinical features
- Severe Acute Respiratory Syndrome
- Caused by SARS associated coronavirus, a new member of Coronaviridae (Am J Clin Pathol 2004;121:574)
- Transmission by respiratory secretions
- Antibodies may not appear until 28 days after onset; molecular tests have greatest yield during second week of illness (Arch Pathol Lab Med 2004;128:1346)
- Outbreaks worldwide in 2002 - 2003 with more than 8,000 cases and over 750 deaths; the last reported case was laboratory associated and occurred in 2004
- Virus localized to pneumocytes (Am J Clin Pathol 2004;121:574)
Microscopic (histologic) description
- Diffuse alveolar damage (DAD) varying based on duration of illness
- 10 or fewer days: acute phase DAD, airspace edema, bronchiolar fibrin and small airway injury
- 11+ days: organizing phase DAD, type II pneumocyte hyperplasia and marked reactive atypia, squamous metaplasia, multinucleated giant cells and acute bronchopneumonia
- Acute phase DAD: hyaline membranes lining alveolar walls, interstitial and airspace edema, interstitial infiltrates of inflammatory cells and vascular congestion
- Organizing phase DAD: fibroblast proliferation in interstitium and air spaces
- Small airway injury: loss of cilia, bronchiole epithelial denudation, deposition of fibrin within the lumen and on exposed basement membranes
- May have coinfections with CMV, Aspergillosis
Positive stains
- SARS associated coronavirus by RT-PCR at autopsy (Mod Pathol 2005;18:1)
Additional references
