384 ' BACTEEIOLOGY. 



would indicate the existence of diverse species although morphologi- 

 cally they may be almost alike. 



Pathogenesis. — Man, rabbits and mice are susceptible. Typical 

 erysipelas results in man from inoculation with pure cultures, as in 

 cases of inoperable carcinoma, etc. Infection in young rabbits fre- 

 quently gives rise to local suppuration, or to severe general symptoms 

 and death. Like the Frankel diplococcus, it is a widely distributed 

 engenderer of inflammatory processes. It may occur in connection 

 with other diseases as diphtheria, scarlet fever, typhoid fever, pneu- 

 monia, tuberculosis, etc. {secondary infection). Or, it may cause a 

 primary infection, in which case the results will depend largely upon 

 the virulence of the germ and the avenue -of infection. Thus, it is 

 the common cause of puerperal fever, erysipelas, otitis, endocarditis, 

 pericarditis, pleurisy, peritonitis and pseudo-diphtheria; of a simple 

 abscess or of general sepsis (pyemia). 



Gonococcus (p. 368). 



Pure human serum was used at first for cultivating this organ- 

 ism. Better results, however, are obtained with human serum or 

 blood added to agar or bouillon (1:2). The serum or blood maybe 

 replaced by ascitic fluid; 1 part of latter 'to 2 or 3 parts of agar or 

 bouillon. Coagulated rabbit serum is said to be as good as human 

 blood. For its preparation see Chapter XIV. 



To isolate the gonococcus the pus should be stirred into liquefied 

 agar (45°) and dilutions in agar should be made in the usual way. The 

 tubes should each contain about 4 c.c. of agar. 2c.c. of freshly drawn 

 human blood (see Chapter XIV) should then be added to each tube, 

 and the mixture poured into Petri dishes. These should then be kept 

 at 35-37 ° . The organism may also be isolated by streaking the pus over 

 agar plates or inclined agar on which human blood has been spread. 

 Or, the material may be spread thoroughly over inclined rabbit , 

 serum. The cultures should be placed at once in the incubator. 



Diagnosis. — Cover-glasses should be prepared from gonorrheal 

 pus while it is fresh, and before it has dried down. It is advisable to 

 dilute the drop of pus with a drop or two of water. The cover-glasses 

 should not be over-heated. They should be stained with simple, or 

 with LofEler's methylene blue. The characteristic form, grouping, 

 presence in pus cells, and the fact that it does not stain by Gram's 

 method will serve to distinguish it from other organisms. It can be 

 detected in blood by the method given for streptococci (p. 364). 



