[The clinical characteristics and staging of severe acute respiratory syndrome]

To investigate the clinical characteristics and to initiate a clinical staging of severe acute respiratory syndrome (SARS).

Retrospective analysis was conducted in the clinical symptoms, physical signs and the results of laboratory examinations from 1170 cases with SARS in Beijing, and the clinical characteristics in different stages of the disease were compared.

The initial symptom of SARS was pyrexia and the temperature was > 38 degrees C. The natural course of fever was about 14 days. In almost all cases, the respiratory symptoms and systemic toxic manifestations were observed. They came to a climax at the second week and then decreased or nearly disappeared after the third week. The physical signs of SARS were not obvious. The moist rales were observed in 43.3% of patients. Hypoxemia was a common characteristic in SARS. The decrease in partial pressure of oxygen in artery and oxygen saturation in pulse oximeter with normal partial pressure of carbon dioxide was found in most patients at the second week. Abnormal chest X-ray including infiltration and consolidation shadows were seen in 100% of patients. The abnormal images could be found at the first day, enlarged during the second week (to a climax at the 8th or 9th day), and then recovered from the 2 week. The amounts of CD(4)(+), CD(8)(+), and CD(3)(+) of peripheral blood were decreased at the early stage and recovered after 2 or 3 weeks. Some patients suffered from temporary multiple organ dysfunctions (mainly impairments of liver and myocardium).

The main clinical manifestations of SARS included respiratory and systemic toxic symptoms. The typical course of the disease was about 4 weeks. The first week could be considered as early stage, the second week as fastigium stage, and from the next two weeks as recovery stage.