METHODS OF DIAGNOSIS 267 



Methods of Diagnosis. For microscopical examination, dried 

 films of the suspected pus, etc., may be stained by any of the 

 simple solutions of the basic aniline stains. We prefer methy- 

 lene- or thionin-blue, as they do not overstain, and the films do 

 not need to be decolorised. Staining for one minute is sufficient. 

 It is also advisable to stain by Gram's method, and it is a good 

 plan to put at one margin of the cover-glass a small quantity 

 of culture of staphylococcus if available, in order to have a 

 standard by which to be certain that the supposed gonococci 

 are really decolorised. Regarding the value of microscopic 

 examination alone, we may say that the presence of a large 

 number of micrococci in a urethral discharge having the 

 characters, position, and staining reactions described above, 

 is practically conclusive that the case is one of gonorrhoea. 

 There is no other condition in which the sum-total of the 

 microscopical characters is present. We consider that it is 

 sufficient for purposes of clinical diagnosis, and therefore 

 of great value; in the acute stage a diagnosis can thus be 

 made earlier than by any other method. The mistake of 

 confusing gonorrhoea with such conditions as a urethral chancre 

 with urethritis, will also be avoided. Even in chronic cases 

 the typical picture is often well maintained, and microscopic 

 examination alone may give a definite positive result. When 

 other organisms are present, and especially when the gonococci 

 are few in number, it is difficult, and in some cases impossible, 

 to give a definite opinion, as a few gonococci mixed with other 

 organisms cannot be recognised with certainty. This is often 

 the condition in chronic gonorrhoea in the female. In the case 

 of the female a drop of secretion should be taken on a platinum 

 loop from the urethra or, with the aid of a speculum, from the 

 cervix uteri, the adjacent parts being cleansed as far as possible 

 by swabbing with sterile cotton wool. Microscopic examination, 

 therefore, though often giving positive results, will sometimes be 

 inconclusive. As regards lesions in other parts of the body, 

 microscopic examination alone is quite insufficient ; it is practi- 

 cally impossible, for example, to distinguish by this means the 

 gonococcus from the diplococcus intracellularis of meningitis. 

 Cultures alone supply the test, and the points above detailed are 

 to be attended to. 



SOFT SORE. 



The bacillus of soft sore was first described by Ducrey in 

 1889, who found it in the purulent discharge from the ulcerated 

 surface; and later, in 1892, Unna described its appearance and 



