Differential diagnosis between SARS and other community acquired pneumonia and evaluation of prognosis with multi-slice spiral CT / 中华放射学杂志

ABSTRACT

Objective To discuss the diagnostic value of multi-slice spiral CT (MSCT) in distinguishing the severe acute respiratory syndrome (SARS) from community acquired pneumonia (CAP), and to evaluate the prognosis in these two groups. Methods A retrospective study was performed on 64 cases with SARS (28 men, 36 women, aged 18-93 yrs, mean age 42.3 yrs) and 46 inpatients with CAP (29 men,17 women, aged 28-88 yrs, mean age 70.1 yrs). Pathogens of respiratory tract were found in 23 patients of CAP. All of patients underwent MSCT scanning of the chest. Results The sensitivity, specificity, and accuracy for diagnosis of SARS using a combination of 3 factors, including ground-glass opacities of lung parenchyma in chest CT, age, and WBC counts were 93.8%, 60.9% and 80.0%, respectively. The sensitivity, specificity, and accuracy for excluding SARS using a combination of consolidation of lung lesions, fiber stripe components and thicken bronchus wall of lung CT in CAP patients were 91.3%, 82.8%, and 86.4%, respectively. The death in SARS and CAP was 7 (10.9%) and 4 (8.7%), respectively. The late follow-up results indicated that 48.8% (21/43 cases) of SARS cases left abnormal manifestations in the lung. The lung sequela of the patients over 50 yrs tended to be severe with the age. Conclusion In outbreak region of SARS, MSCT plays an important role in early diagnosis, but we need to closely combine the density features of lung lesions and other manifestations of lung with clinical condition of patients to increase the accuracy for the differential diagnosis of SARS from CAP. The prognosis of patients over 50 yrs with SARS is relatively poor.