558 PATHOGENIC AEROBIC BACILLI 



BACILLUS OF PURPURA HJEMORRHAGICA OF TIZZONI AND GIO- 



VANNINI. 



Obtained by Tizzoni and Giovannini (1889) from the blood of two children, 

 who died of purpura haemorrhagica following impetigo. 



Morphology. Bacilli with round ends, from 0.75 to 1.3 /* long and 0.2 

 to 0.4 yu broad; often seen in pairs or in groups like streptococci. 



Stains with the usual aniline colors, but not by Gram's method. 



Biological Characters. An aerobic and facultative anaerobic, non- 

 liquefying, non-motile bacillus. Spore formation not observed. Grows in 

 the usual culture media at the room temperature. Upon gelatin plates the 

 colonies at first resemble those of Streptococcus pyogenes. Upon the surface 

 small, opaque points are seen at the end of > forty-eight hours, which at the 

 end of four to five days develop into spherical, yellowish-gray colonies with 

 irregular margins, surrounded by a growth resembling tufts of curly hair. 

 Upon agar the growth is similar, but more rapid and of a pale color, often 

 with a central nucleus surrounded by a net-like marginal zone. Upon 

 blood serum the growth is similar to that upon agar. Upon potato, at 37 

 C., a limited development occurs about the point of inoculation, which has 

 a dark-yellow color. The cultures give off a very penetrating odor. 



Pathogenesis. Pathogenic for dogs, rabbits, and guinea-pigs when in- 

 jected subcutaiieously. Not pathogenic for white mice or pigeons. The 

 symptoms resulting from a subcutaneous injection are said to be fever, al- 

 buminuria and, in some cases, anuria, haemorrhagic spots upon the skin, 

 convulsions ; death occurs in from one to three days. At the autopsy there 

 are found oedema about the point of inoculation , haemorrhages in the skin and 

 muscles, and sometimes in the internal organs and in serous cavities; the 

 blood does not coagulate. The bacilli are found in the subcutaneous con- 

 nective tissue, but not in the blood or in the various organs. Sections show 

 coagulation necrosis of the liver cells and of the renal epithelium. 



BACILLUS OF PURPURA H^EMORRHAGICA OF BABES. 



Obtained by Babes (1890) from the spleen and lungs of an individual who 

 died from purpura haemorrhagica with symptoms of septicaemia. Resembles 

 the bacillus previously described by Tizzoni and Giovannini, and still more 

 that of Kolb ; but, according to Babes, differs in some respects from both of 

 these, although they all belong evidently to the same group. 



Morphology. Bacilli with rounded ends, oval or pear-shaped, about 0.3 /* 

 thick, surrounded by a narrow capsule. 



Stains with the aniline colors, but not deeply, and still less intensely by 

 Gram's method. 



Biological Characters. An aerobic and facultative anaerobic, non- 

 liquefying, non-motile bacillus. Does not form spores. Grows in the usual 

 culture media at the room temperature. In gelatin stick cultures, at the 

 end of three days, a thin, transparent, irregular layer has developed upon 

 the surface, and a whitish, punctate stripe along the line of inoculation. In 

 agar stick cultures an abundant development occurs along the line of punc- 

 ture, and at the end of three days the growth upon the surface consists of 

 small, moist, transparent drops; later of larger, flat, shining, yellowish- 

 white plaques which have ill-defined margins. Upon blood serum the de- 

 velopment is somewhat more abundant in the form of small, white, moist 

 colonies one to two millimetres broad. Upon potato, at the end of three 

 days, moist, whitish drops with ill-defined margins. 



Pathogenesis. Inoculations in the conjunctivas of rabbits produce ecchy- 

 moses of the conjunctiva. At the autopsy numerous haemorrhagic extrava- 

 sations are found in all the organs, especially in the lungs and liver ; the 

 spleen is enlarged ; the bacilli can be recovered in pure cultures from the 

 various organs. Old cultures proved to have lost their virulence. Patho- 

 genic for mice, which die from general infection in the course of a few days ; 



