[Lung pathology of severe acute respiratory syndrome]

To study the morphological features of the lungs obtained from autopsies of severe acute respiratory syndrome (SARS) patients.

Bilateral lungs from 7 patients died from SARS were carefully studied grossly and microscopically. All tissues from these cases were routinely processed and carefully studied.

All lungs from these cases were extremely expanded and became solid. Microscopically, the edema and fibrin exudates in the alveoli was the most common findings, especially in the early phase of the disease. The hyaline membrane was almost always present in the lungs of these cases. The organization of intra-alveolar fibrin exudates along with the interstitial fibrosis led to obliteration of alveoli and consolidation of lungs. The desquamation and hyperplasia of alveolar lining cells was also apparent. Foci of haemorrhage and lobular pneumonia, even diffuse fungal infection were frequently seen in these specimens. Micro-thrombus were easily found in these lungs.

The lung of SARS from autopsy is characterized by edema, intra-alveolar fibrin exudates, hyaline membrane formation, organization of intra-alveolar exudates and fibrosis, which lead to the obliteration of alveoli and consolidation of lungs.