Multiple organ infection and the pathogenesis of SARS

Gu, Jiang; Gong, Encong; Zhang, Bo; Zheng, Jie; Gao, Zifen; Zhong, Yanfeng; Zou, Wanzhong; Zhan, Jun; Wang, Shenglan; Xie, Zhigang; Zhuang, Hui; Wu, Bingquan; Zhong, Haohao; Shao, Hongquan; Fang, Weigang; Gao, Dongshia; Pei, Fei; Li, Xingwang; He, Zhongpin; Xu, Danzhen; Shi, Xeying; Anderson, Virginia M.; Leong, Anthony S.-Y.

In contrast, the suspected, but unconfirmed, cases demonstrated a wide range of pathology that varied with the etiology of each case. In three cases, the pathologic changes in the lungs were similar to those seen in the confirmed cases of SARS. However, the edema, consolidation, hyaline membrane formation, and fibrosis were less prominent, and there was no damage to the pulmonary epithelial cells. Multiple organ infection was a characteristic feature for confirmed cases of SARS, but not for the other patients. The damage to the immune system was found only in the patients who had SARS, but not in patients who had similar symptoms but did not harbor the virus. Neuronal changes with demonstrated SARS virus infection were unique to patients who had SARS, and were not found in the misdiagnosed cases. All controls used in SARS assays were negative, and thereby established the specificity of in situ hybridization and immunohistochemistry procedures. Additional controls, including those for the double labeling, excluded the possibility of interference between the in situ hybridization and the immunohistochemical reactions when performed in combination.