Severe Acute Respiratory Syndrome: Relationship between Radiologic and Clinical Parameters

Abstract

PURPOSE: To quantify severity of severe acute respiratory syndrome (SARS) on chest radiographs and to determine its relationship with clinical parameters. MATERIALS AND METHODS: Forty patients (mean age, 42.90 years ± 14.01 [SD]; median age, 41.5 years; age range, 25-82 years) with clinically diagnosed SARS were evaluated. Heart rate, oxygen saturation, temperature, and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were recorded daily. Severity of lung changes on chest radiographs was scored according to percentage of involved lung. Radiographic scores at days of admission, treatment, and maximal radiographic score were extracted for statistical analysis with clinical parameters. Time to maximal radiographic score from admission and days between onset and beginning of treatment were determined. Correlations between radiographic and clinical parameters were evaluated with Spearman rank correlation. Sex differences with respect to clinical and radiographic parameters were evaluated with Mann-Whitney test. RESULTS: Median chest radiographic scores peaked 5 days after beginning of treatment before they declined. Maximal and treatment radiographic scores were inversely related to oxygen saturation (r = -0.67, P < .001; r = -0.35, P = .03). Admission radiographic score was correlated with admission AST level (r = 0.53, P = .003); treatment radiographic score, with treatment ALT and AST levels (r = 0.43, P = .007; r = 0.42, P = .019); and time to maximal radiographic score, with AST level at maximal radiographic score (r = -0.45, P = .006), admission radiographic score (r = -0.55, P < .001), treatment radiographic score (r = -0.58, P < .001), and admission ALT and AST levels (r = -0.44, P = .007; r = -0.58, P = .001). Treatment delay was associated with AST level at maximal radiographic score (r = 0.53, P = .001), treatment radiographic score (r = 0.60, P < .001), and time to maximal radiographic score (r = -0.36, P = .02). No sex differences occurred with respect to radiographic and clinical parameters (P > .05). CONCLUSION: Severity of lung abnormalities quantified on chest radiographs correlates with clinical and laboratory parameters. © RSNA, 2003.