Micrococcus Gonorrhoeae, Neisser (1879). 



GONOCOCCUS, DIPLOCOCCDS OF GONORRHEA. 



Origin. — Constant in gonorrheal discharges. The disease majr 

 affect any mucous membrane: urethra, bladder, rectum, conjunctiva, 

 uterus, etc. The organism is present in ophthalmia neonatorum, 

 gonorrheal ophthalmia, gonorrheal rheumatism and salpingitis. It 

 may even cause endocarditis and general septicemia. 



Form.— "Biscuit-shaped" microtocci which are usually in pairs, 

 with the flattened surfaces facing each other (Fig. 10 a, p. 44). The 

 diplococcus is usually grouped in masses of 20-40 or more cells. The 

 pus cells are frequently invaded and filled by the gonococci. 



In pure culture the typical diplococcus form is rarely present.. 

 Rounded cubes in irregular masses are frequent. 



Motility. — -Has no real motion. 



Sporulation. — Not known. 



Anilin dyes — Stain readily. It is decolored by Gram's method, 

 especially if the specimen is not washed in water. Excellent double 

 stains can be obtained if the specimen is first treated with dilute 

 eosin or safranin and then with Loffler's methylene blue, or with 

 methyl violet. Methylene blue is best adapted for staining cover- 

 glasses of gonorrheal pus. 



Growth. — Behaves as a strict parasite, and hence can be grown 

 only under very special conditions of soil and temperature. Requires 

 an albuminous medium (see p. 384). 



Flates.— No growth on gelatin or agar plates. On a^ar-serum plates (p. 384) the 

 colonies appear in 2± hours as transparent, finely granular points, which show an indented 

 border. They may become yellowish with coarsely granular center. 



Stai culture.— In a%ar-serum a thin delicate growth forms along the line of inocula- 

 tion. A similar film spreads over the surface. Ascites-agar fi:2) is excellent. 



Streak culture. — On inclined agar-sdrum it yields a glistening, grayish white growth. 

 On blood-agar it forms small transparent discrete colonies which resemble those of the 

 influenza bacillus. On rabbit serum the colonies are minute, transparent, roundish with a 

 raised center; slimy character. 



Ascitic fluid and ordinary bouillon (i : 3) gives at 36° an excellent growth. At first it 

 becomes cloudy and a fine deport forms; eventually, a slight creamy or viscous film 

 forms on the surface; long filaments descend into the liquid. Tne culture dies out in about 

 a week. 



Oxygen requirements. — It is an aerobic organism. 



Temperature. — Growth at 32° to 38°. A temperature of 35°-37° 

 should be maintained, otherwise it will soon die out. Above 40° it is 

 easily killed. Likewise in a few hours at 15°. 



Attenuation. — Dies out very rapidly on some media. May live 

 on rabbit serum at 36° for 3-4-8 weeks. 



Pathogenesis. — Pure cultures of the gonococcus produce typical 

 gonorrhea when introduced into the healthy urethra. The toxin has 

 a like effect. Gonorrheal pus may be inoculated on the mucous mem- 

 branes of animals without the least effect. Intraperitoneal injection 

 into mice produces a non-fatal purulent peritonitis. The gonococcus 

 is, therefore, pathogenic only for man. 



Diagnosis. — See p. 384. 



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