Predicting COVID-19 Disease Severity via Thoracic Computerized Tomography

Patient in hospital during CT examination and radiologist
Could thoracic HRCT semiquantitative scoring offer a rapid and accurate method for identifying patients with severe COVID-19 who are at risk for poor outcomes?

In patients with COVID-19, use of thoracic high-resolution computerized tomography (HRCT) semiquantitative scoring may identify patients with severe disease who have a poor prognosis and are at risk of early death, according to study findings published in Clinical Respiratory Journal.

Researchers sought a rapid and accurate method for identifying patients with severe COVID-19. Toward that end, they conducted a retrospective study of patients with COVID-19 pneumonia to determine the effectiveness of using thoracic HRCT semiquantitative scoring to predict clinical and laboratory COVID-19 disease parameters indicative of disease severity and survival.

The investigators analyzed the records of 277 adult patients hospitalized for COVID-19 pneumonia from March to May 2020 who had undergone thoracic HRCT and semiquantitative scoring in the week after being diagnosed with COVID-19. Patients studied had a median age of 52 years and included 162 men, with 49% of patients having at least 1 comorbidity.

Each patient’s thoracic HRCT was reviewed by a radiologist and assigned what investigators termed “a semiquantitative score” of zero to 25 based on the distribution of lesions in each of the 5 regions of the lungs. Each lung region received a score of zero to 5, with a higher score indicative of more lesions. The final semiquantitative radiologic score represented the sum of scores for the 5 lung regions.

Survival was better in patients who had a radiologic score of less than15, according to Kaplan–Meier analysis (hazard ratio [HR], 4.71; 95% CI, 1.43-15.46; P <.01). The investigators therefore identified the radiologic score of 15 as the most appropriate cutoff value for determining survival (area under the curve [AUC], 0.615; 95% CI, 0.554-0.617; P =.106). When patients studied were divided based on the cutoff value of 15, a significant difference in survival was observed between patients with scores below 15 vs those with higher scores (95% Cl, 46.7-57.5; P <.001).

Using univariate analysis, investigators evaluated the relationships between patients’ radiologic scores and their age, sex, presence of comorbidity, laboratory values, and vital signs. The analysis found the radiologic scores were significantly correlated with advanced age, lymphopenia, low oxygen saturation, high ferritin level, D-dimer.

Positive correlations were also found between the radiologic score and C-reactive protein, aspartate aminodehydrogenase, lactate dehydrogenase, ferritin, D-dimer, and pro-B-type natriuretic peptide in the radiologic score and nonparametric correlation analyses; however, negative correlations were observed for oxygen saturation and partial oxygen pressure.

Study limitations include the retrospective design and analysis of data from a single center. In addition, although the researchers excluded cases with common sequelae changes that could affect the semiquantitative score, respiratory artifacts occurring during the HRCT may have affected scoring in patients with severe tachypnea and dyspnea.

Study authors concluded that patients with radiologic semiquantitative scores of 15 and above had a poor prognosis and were at risk for early death. In these patients, “close follow-up and early antiviral treatment may be effective to reduce mortality rates,” the investigators noted.


Komurcuoglu B, Susam S, Batum O, et al. Correlation between chest CT severity scores and clinical and biochemical parameters of COVID-19 pneumonia. Clin Respir J. Published online June 24, 2022. doi:10.1111/crj.13515

This article originally appeared on Pulmonology Advisor