Although indications for admission were not clearly defined in this study, the majority of the inpatients were those who were suspected to have severe disease such as pneumonia and to have risk factors for severe disease such as infants and bronchial asthma. However, it might be possible that excessive concern of parents on fatality of this infection in part affected on admission of the uncomplicated cases. Among the 217 inpatients, we selected 80 patients with pneumonia and 137 patients without pneumonia, based on the chest radiographs. The chest radiographic patterns of admitted patients were reviewed and classified by two pediatricians (KY Lee and JW Rhim) and one pediatric radiologist (JC Kim). The patients with chest radiographic patterns that showed increased nodular densities along the bronchial trees unilaterally or bilaterally, were designated the bronchopneumonia group (49 patients). Patients with a distinctive large patch of infiltration, segmental or lobar consolidations were designated the segmental/lobar pneumonia group and regarded as having a severe pneumonia (31 patients). The first day of fever was regarded as the first day of illness. Among pneumonia patients, we tried corticosteroid treatment for 17 patients with severe pneumonia. As for indication of corticosteroids (methyprednisolone, MP or prednisolone), the subjects had severe respiratory distress with hypoxemia at presentation (12 cases) or during hospitalization (5 cases) requiring O 2 therapy (9,10). We compared the clinical and laboratory characteristics of the different groups.