Purpose: The purpose of this study was to assess the high-resolution CT findings of paediatric patients who had pulmonary infections following bone marrow transplantation (BMT), and to evaluate the differential diagnosis through high-resolution CT of the various pathogens responsible for pulmonary infections after BMT.
Patients and methods: The study included 35 consecutive patients who had documented pulmonary infection, high-resolution CT of the chest performed within 24h of the beginning of symptoms, and proven diagnosis within 1 week of the onset of symptoms. The pulmonary infections were due to viruses (n=16), bacteria (n=9), fungi (n=9), and protozoa (n=1). Two radiologists analyzed the CT scans and reached final decisions regarding the findings by consensus.
Results: Four patients with confirmed pneumonia had normal high-resolution CT scans. Regarding the viral infections, the most frequent features were areas of ground-glass attenuation (43.7%) and small centrilobular nodules (31.2%). Airspace consolidation (88.9%), small centrilobular nodules (22.2%) and ground-glass attenuation (22.2%) were the most frequent findings in patients with bacterial pneumonia following BMT. Large nodules were seen in 66.7% of the patients with fungal pneumonia, and in only one case of virus infection. The "halo sign" (n=5) was seen only in patients with fungal pneumonia.
Conclusion: In conclusion, the main causes of pulmonary infection in paediatric patients following BMT share similar high-resolution CT findings. Large nodules and "halo sign" are more common in patients with fungal infections.