Recent studies showed that the sensitivity of ultrasound for diagnosing pneumonia is at least comparable to chest x-ray. However, little is known about the ultrasound characteristics of different types of pneumonia. Therefore the aim of our study was to evaluate and compare the ultrasound characteristics of lung infiltrates in different types of pneumonia in children.
In our prospective study, we included 117 children hospitalized because of community acquired pneumonia, caused by bacteria, viruses and Mycoplasma pneumoniae (atypical pneumonia) in 50, 39 and 28 subjects, respectively. Lung ultrasound was performed in the first 24 hours after admission and the investigation was repeated after 48-72 hours in 105 subjects. Size (largest diameter) and localisation (unilateral/bilateral) of infiltrates were recorded.
Lung infiltrates were detected with ultrasound in 115 (98.3%) subjects, compared to 95 (81.2%) subjects with infiltrates seen on chest x-ray (p<0.01). Bilateral infiltrates were present on ultrasound altogether in 28 (24.4%) subjects, of them in 2 (4%) with bacterial pneumonia, in 9 (32.1%) with atypical pneumonia and in 17 (45.9%) subjects with viral pneumonia (p<0,01). Mean infiltrate size was 3.9 cm, 3.3 cm and 1.8 cm for bacterial, atypical and viral pneumonia, respectively (p=0.03). Second ultrasound showed significant regression in 41 (85.4%) subjects with bacterial pneumonia, in 3 (12.5%) subjects with atypical pneumonia and in 3 (9.1%) subjects with viral pneumonia (p<0.01).
Chest ultrasound is not only sensitive method for the detection of pneumonia in children, but it can also help in the determination of etiology. However, larger prospective studies are warranted to support our findings.