BACTERIUM GRANULOSIS 901 



Metabolism. — Strict anaerobe. Grows best at 37° C. ; no growth at room tempera- 

 ture. When used to artificial conditions, it grows best on Fildea' agar and blood agar ; 

 it also grows well in coli-broth. In our experience it does not grow on the V or X factors, 

 either alone or in combination (see Chapter 33). Does not hsemolyse horse blood. 

 Optimum pH for growth 7-6 ; limits 7-0-8-0. 



Biochemical. — Acid is produced in dextrose. Indole negative. Nitrates not reduced. 

 Catalase negative. Methylene blue reduction negative. 



Serological. — Agglutinins are formed by injection of cultures into rabbits, but a 

 serological study of different strains of the organism has not been made. 



Pathogenicity. — Was originally suspected of being responsible for human influenza, 

 but is now regarded as having no causal relationship to this disease. Is mildly patho- 

 genic for rabbits, but loses its virulence after artificial culture for some time in the labora- 

 tory. Injection of mass cultures intratracheally into rabbits produces a rise of tem- 

 perature in 24 hours ; usually a conjunctivitis, and a mononuclear leucojiaenia. The 

 symptoms disappear in 2 to 3 days, and the rabbit recovers. If killed during the reaction, 

 the rabbits are found to have voluminous lungs, affected with ojdema and emphysema. 

 Numerous haemorrhages, discrete or diffuse, are seen on the surface of the lungs. The 

 pleura is not involved. On section the lungs drip a frothy, blood-stained fluid, and haemor- 

 rhages are seen scattered through the parenchyma. The trachea and bronchi contain 

 a muco-purulent exudate, covering an exfoliated and haemorrhagic epithelium. The 

 organisms may be recovered from the lungs in pure culture, using Smith- Noguchi medium. 

 Much the same reaction is produced by intratracheal moculation of guinea-pigs. Non- 

 pathogenic to monkeys, injected intratracheally or subconjunctivally. 



Several other tiny anaerobic bacilli have been isolated from the nasopharynx of healthy 

 and diseased persons, differing from Bact. pneumosintes in cultural reactions, patho- 

 genicity, and certain other respects (OUtsky and Gates 19226, Gates 1926). Olitsky 

 and McCartney (1923) found them in the nasal washings of persons with colds and in 

 normal persons. Mills, Shibley and Dochez (1928) found them in 75 per cent, of normal 

 persons. This high percentage was observed only when buffered broth was used for 

 the nasal irrigation ; Ringer's fluid gave much lower figures. The bacilli were of variable 

 morphology, and appeared by agglutination tests to belong to several different types. 

 In this country Garrod (1928) has demonstrated similar filter-passing, anaerobic. Gram- 

 negative organisms in the upper respiratory, tract of both healthy and diseased subjects. 

 He states that morphologically they appear either as very tiny cocci, about \ the diameter 

 of a staphjHococcus, or as very short, sometimes curved bacilli. These organisms can 

 be cultivated anaerobically on rabbit blood agar. 



Bacterium granulosis. 



This organism was isolated by Noguchi (1927) from American Indians suffering from 

 trachoma. It is a very small Gram-negative bacillus, with a tendency to pointed ends 

 and a diploid arrangement. In young blood-agar cultures it measures 0-8-1-2 /j, in length 

 and 0-2-0-3 /u in breadth. In older cultures large irregular involution forms are common. 

 In the condensation water of blood-agar slopes the organism is actively motile by a single 

 polar flagellum. It has a superficial resemblance to G. xerosis, but it is smaller. Gram- 

 negative and motile. It was first cultivated on semi-solid leptospiral medium, in which 

 it gives rise to a diffuse nebulous greyish-white growth in the uppermost centimetre, extend- 

 ing for some distance down the stab. No growth occurs on agar, but on horse blood agar 

 incubated at 30° C. minute, shiny, almost transparent or slightly greyish, circular, convex 

 colonies are evident in 48 hours, which later increase in size and acquire a greyish opalescence 

 and a viscous consistency. Growth occurs best at 30" C, and hardly at all at 37° C. ; 

 the lower limit appears to be about 15° C. The optimum H-ion concentration for growth 

 is pH 7-8, and the range 6-8-8-8. No growth occurs under strict anaerobic conditions. 

 When freshly isolated the organism is devoid of fermentative activity, but after cultivation 

 in the laboratory for some months it is said to produce acid from a number of sugars. 



