FEATURES OF CLINICAL STAGES AND TYPES OF SEVERE ACUTE RESPIRATORY SYNDROME AND THEIR CLINICAL SIGNIFICANCE / 解放军医学杂志

ABSTRACT

Objective To study features and significance of clinical stages and types of severe acute respiratory syndrome (SARS). Methods The clinical features of 330 patients with SARS were analyzed by SPSS 11.0 and SDAS software packages, and the standard for classification of clinical stages and types of SARS were studied. Results The disease course of SARS could be divided into four stages, namely, incubation stage, initial stage, climax stage and convalescence stage. The period of incubation stage was 1~12 (5.70?2.45) days. The initial stage was the pathoformic phase during 1 st~10 th (3.98?2.48) days after the onset. The fever was the first symptom and there were usually no catarrhal symptoms. Meanwhile, no abnormality was found in the chest X-ray examination. The climax stage included 3 sequential phases of pulmonary inflammatory exudation, pulmonary tissue consolidation and ARDS or multi-organ failure. In the phase of pulmonary inflammatory exudation, there were serious cough, mild shortness of breath and hypoxemia. Furthermore, chest X-ray examination showed that there was exaggeration of lung markings, haziness or patchy opacity. In the phase of pulmonary tissue consolidation, type I respiratory failure was usually seen in the patients. Shortness of breath and hypoxemia became more serious. Chest X-ray examination showed that the area of consolidation continued to enlarge to include the entire lung. The convalescence stage usually appeared 3 weeks after the onset and lasted for 5～56 (24.37?8.81) days. This stage could further be divided into phase I (complete recovery) and phase II (possible existence of pulmonary fibrosis). SARS could be clinically classified into mild type (ordinary type), severe type and extremely severe type (fulminant type) with a mortality of zero, 5.76% and 61.54%, respectively. There were very great differences in clinical features in three types of SARS. Conclusions SARS could be divided into the incubation stage, initial stage, climax stage and convalescence stage. The climax stage included 3 phases, i.e. pulmonary inflammatory exudation, pulmonary tissue consolidation, and ARDS or MOF. The convalescence stage could be divided into phase I (complete recovery) and phase II (possible existence of pulmonary fibrosis). SARS could be classified as mild type, severe type and extremely severe type.