CHAPTER XI 

 GONOCOCCUS 



The gonococcus occurs in the genito-urinary tract of carriers and in the 

 affected organs of infected persons. It is not found outside the human body. 



Morphology. The gonococcus occurs in pairs, the cocci arranged like coffee 

 beans, ovoid with flat sides in apposition. The long diameter of the gonococcus 

 is from 0.6 to 0.8 p. It stains with all the anilin dyes and is Gram negative. 

 The gonococcus does not form spores and is non-motile. Morphologically and 

 by staining this organism is indistinguishable from the meningococcus. 



Growth. This organism cannot be satisfactorily cultivated on plain agar, 

 gelatin or bouillon. Occasionally scant growth may be obtained in gelatin 

 stabs (without liquefaction), on LoefHer's serum and on blood-smeared agar; 

 but Wertheim's medium or some of its modifications serve best for the 

 cultivation of the gonococcus. 



To tubes containing 6 cc. of neutral glycerin agar, liquefied and cooled to 

 5oC., 4 cc. of sterile blood serum or ascitic fluid should be added. After mix- 

 ing the serum and agar the tubes are slanted. Smears made on this medium 

 show growth in 1 8 to 24 hours at 37C. The colonies are round, pin-head size, 

 whitish and tenacious. After from 3 days to a week they usually die out if 

 not transplanted. 



It is said that the addition of a piece of sterile rabbit testicle to culture 

 medium favors the propagation of gonococci. While it is usually difficult to 

 obtain a growth in tubes planted with gonococci directly removed from the 

 human body, after the organisms have been successfully cultured and trans- 

 planted several times on media, they usually grow more regularly, more abun- 

 dantly and less exacting as to the composition of the medium. 



Gonococci will not grow in the presence of free moisture; there should be 

 no water of condensation in tubes used for their cultivation. 



C. C. Worden recommends the following medium for obtaining pure cultures 

 of gonococci from material containing other organisms in addition to the 

 gonococci, and states that it is a good medium for the cultivation of gonococci: 



Sodium chloride i . 080 Gm. 



Potassium chloride o . 045 Gm. 



Calcium chloride 0.025 Gm. 



Sodium bicarbonate . 0.020 Gm. 



Agar o . 250 Gm. 



Nutrient broth 20 cc. 



Distilled water 100 cc. 



Filter through cotton into test-tube and sterilize once in autoclave. 

 Sugars are not fermented and indol is not formed. 



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