Pneumatoceles on chest radiograms in a child with pneumonia are seen in infection

staphylococcal pneumonia : pneumonic process is diffuse but soon lesions suppurate and cause bronchoalveolar destruction multiple microabscesses erode the bronchial wall and discharge their contents in bronchi. several pneumatocoeles form and they fluctuate in size over time ultimately resolving and disappearing in few weeks to months in Xray pneumatocoeles persist as thin walled cysts.they are also seen in klebsiella pneumonia Ref : ESSENTIAL PEDIATRICS,O.P.GHAI, PG NO:353,7thedition