Objective: The objective of our study was to describe lung changes on serial chest radiographs from patients infected with the acute Middle East respiratory syndrome corona-virus (MERS-CoV) and to compare the chest radiographic findings and final outcomes with those of health care workers (HCWs) infected with the same virus. Chest radiographic scores and comorbidities were also examined as indicators of a fatal outcome to determine their potential prognostic value.

Materials and methods: Chest radiographs of 33 patients and 22 HCWs infected with MERS-CoV were examined for radiologic features indicative of disease and for evidence of radiographic deterioration and progression. Chest radiographic scores were estimated after dividing each lung into three zones. The scores (1 [mild] to 4 [severe]) for all six zones per chest radiographic examination were summed to provide a cumulative chest radiographic score (range, 0-24). Serial radiographs were also examined to assess for radiographic deterioration and progression from type 1 (mild) to type 4 (severe) disease. Multivariate logistic regression analysis, Kaplan-Meier survival curve analysis, and the Mann-Whitney U test were used to compare data of deceased patients with those of individuals who recovered to identify prognostic radiographic features.

Results: Ground-glass opacity was the most common abnormality (66%) followed by consolidation (18%). Overall mortality was 35% (19/55). Mortality was higher in the patient group (55%, 18/33) than in the HCW group (5%, 1/22). The mean chest radiographic score for deceased patients was significantly higher than that for those who recovered (13 ± 2.6 [SD] vs 5.8 ± 5.6, respectively; p = 0.001); in addition, higher rates of pneumothorax (deceased patients vs patients who recovered, 47% vs 0%; p = 0.001), pleural effusion (63% vs 14%; p = 0.001), and type 4 radiographic progression (63% vs 6%; p = 0.001) were seen in the deceased patients compared with those who recovered. Univariate and logistic regression analyses identified the chest radiographic score as an independent predictor of mortality (odds ratio [OR], 1.38; 95% CI, 1.07-1.77; p = 0.01). The number of comorbidities in the patient group (n = 33) was significantly higher than that in the HCW group (n = 22) (mean number of comorbidities, 1.90 ± 1.27 vs 0.17 ± 0.65, respectively; p = 0.001). The Kaplan-Meier analysis revealed a median survival time of 15 days (95% CI, 4-26 days).

Conclusion: Ground-glass opacity in a peripheral location was the most common abnormality noted on chest radiographs. A higher chest radiographic score coupled with a high number of medical comorbidities was associated with a poor prognosis and higher mortality in those infected with MERS-CoV. Younger HCWs with few or no comorbidities had a higher survival rate.