Cavitary necrosis complicating pneumonia in children: sequential findings on chest radiography.

Abstract
The objective of this study was to describe the sequential clinical and radiographic findings of cavitary necrosis complicating pneumonia in childhood. A study group of 17 children (mean age, 6 years) was identified by reviewing CT examinations of all patients who underwent CT of the chest to evaluate possible complications of pneumonia over a 3-year period. Children included in the study group were those who met the criteria for cavitary necrosis: loss of lung architecture, decreased enhancement, and multiple cavities with thin, nonenhancing walls. In the 17 identified cases, sequential chest radiographs were reviewed for visibility of a lung cavity. Long-term follow-up radiographs were evaluated for persistent abnormalities. Ten of the 17 cases of cavitary necrosis seen on CT showed cavities at some time on radiography: one cavity was visible at the time of diagnosis on CT and nine were visible only later. All three cavities that were predominantly air-filled on CT were revealed by radiography, whereas 50% (7/14) of predominantly fluid-filled cavities were revealed by radiography. Eleven children underwent follow-up radiography more than 40 days after the diagnosis of cavitary necrosis. Radiographs of those 11 children showed clear lungs without pulmonary sequelae. In children, cavitary necrosis is associated with severe illness; however, cases usually resolve without surgical intervention, and long-term follow-up radiography shows clear lungs without pulmonary sequelae. Evidence of cavitary necrosis complicating pneumonia is often seen on CT before or in the absence of findings on chest radiography.