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

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.

Age-related changes in blood lymphocyte subsets of south Indian children.

BACKGROUND: Enumeration of lymphocyte subsets has been widely used for the diagnosis and monitoring of several haematological and immunological disorders. Various studies have demonstrated age, sex and racial differences in lymphocyte subset expression. Reference values are not available for Indian children and there is a need for this information to replace commonly used, but inappropriate, adult lymphocyte subset ranges. METHODS: One hundred thirty-eight healthy children between 3 and 15 years of age, attending a local government school in Chennai, South India were Included in the study. Haemoglobin levels, and total and differential cell counts were determined using an automated counter and lymphocyte subsets were analysed by flowcytometry. RESULTS: The mean (SD) absolute lymphocyte count declined with age from 4338 (1031) at 3 years to reach a plateau of 3096 (914) at 11-13 years (p < 0.05). A significant decline was also observed in the absolute numbers of CD3+, CD4+, CD8+ and CD19+ cells. However, the percentage values of CD3+, CD4+, CD8+, CD16/56+ cells and the CD4/CD8 ratio remained fairly stable across the age range. CONCLUSION: Our data would prove useful in interpreting disease-related changes in lymphocyte subsets in Indian children of different age groups. Age-related decrease in the absolute lymphocyte count as well as numbers of CD4 and CD8 cells was found to occur between the ages of 3 and 11 years. A normogram relating age to CD4 count has been developed.