Pneumococcal pneumonia in hospitalized patients. Clinical and radiological presentations.

The clinical and radiological features of pneumococcal pneumonia were studied in 94 hospitalized patients. Fifty-seven (61%) had a bronchopneumonic pattern on roentgenogram, and 37 (39%), a lobar pattern. Eighty-two (87%) of the patients in both roentgenographic classifications had one or more underlying disease states. There was no difference in the frequency of heart disease, diabetes, chronic pulmonary disease, or malignancy between the two categories. Sputum Gram's stains were also similar in both patterns. Twenty (54%) of the 37 patients with the lobar pattern were bacteremic compared with only five (9%) of the 57 patients with the bronchopneumonic pattern; all five patients with bronchopneumonia and bacteremia had an associated malignancy. Although a lobar pattern is usually emphasized in the diagnosis of pneumococcal pneumonia, this study showed that the majority of patients hospitalized with pneumococcal pneumonia had a roentgenographic bronchopneumonic pattern rather than the classic lobar pattern. Thus, patients with the bronchopneumonic pneumococcal pneumonia pattern may be underdiagnosed. The implications are important both for treatment and for epidemiologic data used in the selection of pneumococcal types for prophylactic vaccines.