[The early warning signs of deterioration of severe acute respiratory syndrome].

Zhao, Min; Fan, Rong; Jiang, Tian-jun; Chen, Zuo; Xie, Gao-qiang; Xiao, Feng; Wu, Yang-feng; Chen, Bo-wen; Han, De-min

OBJECTIVE To explore the risk factors related to severe cases of severe acute respiratory syndrome (SARS) in order to find the early warning signs of deterioration of this disease. METHODS Three hundred and fifty-five patients with severe SARS and 841 patients with regular SARS from Beijing were studied. RESULTS Patients with elder age or with comorbid conditions were more likely to develop into severe cases. Data also showed the following characteristics in those severe cases: sustained fever, tachycardia (pulse rate being over 100 per minute), persistent decrease in lymphocytes (< 0.9 x 10(9)/L), increase in neutrophils (> 7.1 x 10(9)/L, 80%), and rapid changes in abnormal chest X-ray. The Cox proportional hazard multi-variable stepwise analysis showed the prediction model of severe SARS included age, comorbid disease, body temperature being still abnormal after 2 days of hospitalization, neutrophil percentage began to increase steadily to more than 80% after 3 days of hospitalization, counts of lymphocytes persisted < 0.9 x 10(9)/L after 4 days of hospitalization. CONCLUSIONS According to patient's age, comorbid conditions, one can effectively predict the development of the severe SARS by closely monitoring temperature, pulse rate, the counts of lymphocytes and percent of neutrophils.