Serological varieties of Klebsiella pneumoniae in pneumonia

118 K. pneumoniae cultures isolated from the pulmonary tissue samples, taken during autopsy from 33 patients who had died of pneumonia, and from the sputum of 19 living patients with chronic pneumonia, as well as 2 strains, K1 and K2, from the International Reference Klebsiella collection, formerly known as Friedländer's bacilli A and B, were studied. Besides K. pneumoniae K1 and K2, 10 other serovars of these bacteria, viz. K9, K11, K13, K16, K18, K19, K20, K62, K64, K82, were isolated, both as pure cultures and in association with other organisms, from the foci of inflammation in the pulmonary tissue in acute pneumonia. The K. pneumoniae serovars isolated from the sputum samples were essentially the same as those isolated from the autopsy material. The disease was found to have similar clinical and pathological manifestations irrespective of a K. pneumoniae serovar isolated in each particular case, which was indicative of the similar pattern of pulmonary tissue lesions characteristic of Friedländer's pneumonia. A new name for the nosological form of this disease is proposed: Klebsiella pneumonia instead of Friedländer's pneumonia. K. pneumoniae should be considered as pathogenic microorganisms, which was formerly known in respect of Friedländer's bacilli.