CHRONIC PULMONARY INFECTION DUE TO THE FRIEDLÄNDER BACILLUS

Abstract

Friedländer's pneumonia is an acute pulmonary infection, usually fatal, caused by Bacillus mucosus-capsulatus and characterized particularly by a viscid, bloody sputum and lobular involvement of the lung parenchyma with a marked tendency to the formation of secondary multiple abscesses. In 1882, Friedländer described a "micrococcus" which he took to be the cause of lobar pneumonia. However, after Frankel and Weichselbaum had shown in 1886 that the pneumococcus was the causative organism in most cases of acute lobar pneumonia, it was found that the so-called "micrococcus" of Friedländer was in reality a short, gramnegative bacillus. This bacillus occurs either as a primary or a secondary invader in about 5 or 10 per cent of all cases of acute lobar pneumonia. BACTERIOLOGY The bacillus of Friedländer varies greatly in size and morphology. Usually it is short and rather broad, with rounded ends. Its length varies from 0.6 to 5 microns and its