Observations on the L-Organism of Klieneberger

Abstract

The streptobacillus moniliformis, under various names, has been reported to occur in rats in pulmonary disease, 1 , 2 , 3 otitis media, 4 and as inhabitant of the nasopharynx; 5 in mice, as an agent of systemic disease; 5 , 6 , 7 in humans, in fevers following the bite of rats or other small animals, 8-11 or as an epidemic 12 or isolated 13 infection of variable transmission. A similar organism has been observed by Smith 14 in pneumonia of calves. All organisms described in the above reports are characterized morphologically by huge bulbous or club-like swellings, which appear early in a developing culture, and later make up a large part of it. These swollen forms gained great theoretical importance when Klieneberger 15 observed that they really represent an organism separate from the bacillus, which could be cultivated and grown alone, showing no reversion to bacillary forms in the 2 years of observation. Furthermore, the properties of this organism (designated “L” by Klieneberger) differ in many respects from those of bacteria and fungi, and resemble the curious organisms of pleuropneumonia bovis and of agalactia. The L-or-ganism being very soft and fragile, its real form is difficult to ascertain. It is known, however, to be very pleomorphic, exhibiting large disc-like forms, small filter-passing granules, and filaments of greatly varying size. Thus we have an entirely new type of observation before us: The cultures of a bacillus causing disease both in animals and in man appear to consist of 2 organisms, one of which shows properties associating it with organisms usually classed with the filtrable viruses. Recently Klieneberger 3 has found that the pleuropneumonia-like organism is frequently found alone, without the bacillus, in the lung-abscesses of rats. In contrast, however, all observations indicate that the streptobacillus cannot be freed of the characteristic swollen forms of the L-organism.