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PubMed search: SARS [title] pulmonary

Elliot Weisenberg, M.D.
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Cite this page: Weisenberg E. SARS. website. Accessed September 26th, 2023.
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
Additional references
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