Radiological features of round pneumonia in children: 10 years of experience

Abstract

Aim: Round pneumonia (RP) is a type of pneumonia that appears round on imaging studies and usually occurs in children. Although round pneumonia is a well-known clinical condition, few publications available in the literature describing the imaging findings and features of round pneumonia. The purpose of the review was to evaluate the chest radiographs, chest ultrasonography and CT findings associated findings of round pneumonia as compared to the published literature. Material and Method: 65 children who were diagnosed with round pneumonia in our hospital between December 2010 and July 2020 were included in our study. Initial chest radiographs and CT scans were evaluated for lesion parameters: number, margin, opacity, size, location, and hilar LAP and air bronchogram accompaniment. Follow-up chest radiographs were evaluated for temporal variation (resolution or progression to lobar pneumonia). The findings of the patients who underwent chest ultrasonography were recorded. Results: The mean age of the 65 children with round pneumonia included was 6.2 years and their ages ranged from 9 months to 16 years. Evaluation of chest radiographs showed one lesion in each of 63 children (96%, 63/65) and two lesions in two children (4%, 2/65). Lesion margins were sharp in 84% (55/65) and the mean diameter of lesions was 2,5 cm with a range of 1.5–9.5 cm. On the radiograph, the opacity of round pneumonia was low (60%, 39/65) and hilar lymphadenopathy was detected in 1 out of 5 patients (20%, 13/65). The location of the lesion tended to be posterior (51%, 33/65) and upper lobe (54%, 35/65). On chest ultrasonography, consalidation was seen in 8 patients, consalidation and pleural effusion were seen in 3 patients. CT images were available in 11 (17%) children. Pleural thickening or satellite lesions were not observed in any of the patients on tomography. Follow-up radiographs tended to show resolution in 95% (62/65) and progression to lobar pneumonia in 4.6% (3/65). 1 patient progressed to lobar pneumonia and died. 2 patients developed cavitary pneumonia. Conclusion: Round pneumonia is a benign type of pneumonia that is mostly seen in children due to its physiopathology. Most patients with RP recover clinically and radiologically after antibiotic therapy. Although there are many diseases in the differential diagnosis, knowing the radiological features facilitates the diagnosis and prevents unnecessary diagnostic and imaging studies.

Keywords

• Round pneumonia
• Children
• Radiology
• Chest Radiogarphy
• Computed Tomography.

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