[Clinical course of pulmonary eosinophilic granuloma--CT evidence of lesion evolution]

We reviewed a clinicopathological study of pulmonary eosinophilic granuloma focusing on the evolution of pulmonary lesions in chest CT scans. Between 1990 and 2002, five patients with pulmonary eosinophilic granuloma were admitted to our hospital. Clinical features, chest radiographs, pathological characteristics and treatments were evaluated. The scans were repeated in four patients at intervals of at least eight months. All patients were men who smoked. The age at onset of the pulmonary disorders ranged from 22 to 45 years, with a mean of 33 years. Most of the initial chest CT scans showed nodular lesions and thin-walled cysts, but the nodular lesions disappeared or were transformed into cystic lesions in the later scans. Most of the final scans revealed thin-walled cysts and emphysematous lesions. The histopathological characteristics of the nodular lesions in the chest CT were correlated with cellular granulomas mainly composed of Langerhans cells and eosinophils, and small granulomas were also seen in the thin fibrous walls of the cysts. All patients quitted smoking and three showed improvement of the pulmonary lesions within three months.