Korean J Radiol.  2007 Dec;8(6):466-474. 10.3348/kjr.2007.8.6.466.

A Correlation between the Severity of Lung Lesions on Radiographs and Clinical Findings in Patients with Severe Acute Respiratory Syndrome

• Wan YL
• Tsay PK
• Cheung YC
• Chiang PC
• Wang CH
• Tsai YH
• Kuo HP
• Tsao KC
• Lin TY

• KMID: 1089433
• DOI: http://doi.org/10.3348/kjr.2007.8.6.466

Abstract

OBJECTIVE: The purpose of this study was to quantify lesions on chest radiographs in patients with severe acute respiratory syndrome (SARS) and analyze the severity of the lesions with clinical parameters. MATERIALS AND METHODS: Two experienced radiologists reviewed chest radiographs of 28 patients with SARS. Each lung was divided into upper, middle, and lower zones. A SARS-related lesion in each zone was scored using a four-point scale: zero to three. The mean and maximal radiographic scores were analyzed statistically to determine if the scorings were related to the laboratory data and clinical course. RESULTS: Forward stepwise multiple linear regression showed that the mean radiographic score correlated most significantly with the number of hospitalized days (p < 0.001). The second most significant factor was the absolute lymphocyte count (p < 0.001) and the third most significant factor was the number of days of intubation (p = 0.025). The maximal radiographic score correlated best with the percentage of lymphocytes in a leukocyte count (p < 0.001), while the second most significant factor was the number of hospitalized days (p < 0.001) and the third most significant factor was the absolute lymphocyte count (p = 0.013). The mean radiographic scores of the patients who died, with comorbidities and without a comorbidity were 11.1, 6.3 and 2.9, respectively (p = 0.032). The corresponding value for maximal radiographic scores were 17.7, 9.7 and 6.0, respectively (p = 0.033). CONCLUSION: The severity of abnormalities quantified on chest radiographs in patients with SARS correlates with the clinical parameters.

Keyword

Lung, diseases; Lung, radiography; Severe acute respiratory syndrome

MeSH Terms

Adolescent
Adult
Aged
Aged, 80 and over
Biological Markers/blood
Blood Gas Analysis/statistics & numerical data
Female
Humans
Intubation, Intratracheal/statistics & numerical data
Length of Stay
Lung/*radiography
Lymphocyte Count/statistics & numerical data
Male
Middle Aged
Observer Variation
Predictive Value of Tests
Prognosis
Retrospective Studies
Severe Acute Respiratory Syndrome/blood/*diagnosis/mortality
Severity of Illness Index
Survival Analysis

Figure

• 

  Fig. 1 Serial radiographic changes in a 26-year-old female with SARS who recovered after one month. A. A close-up view of a chest radiograph in the posteroanterior projection obtained 4 days after fever onset shows a subtle ground glass density in the lateral aspect of the right upper lung (arrows) (radiographic score = 1). B. A close-up view of a follow-up chest radiograph in the anteroposterior projection obtained 8 days after fever onset shows progression of air space opacities to consolidation (black arrows), extending to the upper (small white arrow) and middle (large white arrow) zones of the right lung (radiographic score = 3). C. A follow-up chest radiograph in the anteroposterior projection obtained 14 days after fever onset shows progression of the opacities involving the upper, middle and lower zones of the right lung, as well as the middle and lower zones of the left lung. The lesions had progressed to a maximal radiographic score of 13, as shown on this radiograph in the clinical course. D. A follow-up chest radiograph in the anteroposterior projection obtained 24 days after fever onset shows regression of the lung opacities involving the right lung, and the middle and lower zones of the left lung (radiographic score = 6). E. A follow up chest radiograph in the posteroanterior projection obtained one month after fever onset. The lung lesions had completely resolved. The patient recovered and was discharged after one month of hospitalization.

• 

  Fig. 2 Serial radiographic changes in a 34-year-old female with SARS. The patient expired on the tenth day after fever onset. A. A close-up view of a chest radiograph in the posteroanterior projection obtained 3 days after fever onset shows opacity (arrow) mainly in the medial aspect of the right middle lung (radiographic score = 1). B. A close-up view of a chest radiograph in the posteroanterior projection obtained 4 days after fever onset shows progression of the right perihilar opacity (black arrow) in the right middle and right lower lung zone (white arrows) (radiographic score = 3). C. A Follow-up chest radiograph in the anteroposterior projection obtained 8 days after fever onset shows progression of the right perihilar opacity to the right upper zone (white arrow), middle and lower lung zones (black arrows) (radiographic score = 4). D. A follow-up chest radiograph in the anteroposterior projection obtained 9 days after fever onset shows marked progression of lung opacities to the right lung as well as to the middle and lower zones of the left lung (radiographic score = 12). E. A follow-up chest radiograph in anteroposterior projection obtained 10 days after fever onset shows progression of lung opacities to involve mainly the middle and lower zones of bilateral lungs (radiographic score = 14). The patient expired on the tenth day after fever onset.

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