BACILLUS DIPHTHERIA 353 



standing features which ought to be considered in connection 

 with its bacteriology. In addition to the formation of false 

 membrane, which may prove fatal by mechanical effects, the 

 chief clinical phenomena are the symptoms of general poisoning, 

 great muscular weakness, tendency to syncope, and albuminuria ; 

 also the striking paralyses which occur later in the disease, 

 and which may affect the muscles of the pharynx, larynx, and 

 eye, or less frequently the lower limbs (being sometimes of 

 paraplegic type), all these being grouped together under the 

 term " post-diphtheritic paralyses'." It may be stated here that all 

 these conditions have been experimentally reproduced by the 

 action of the bacillus of diphtheria, or by its toxins. Other 

 bacteria are, however, concerned in producing various secondary 

 inflammatory complications in the region of the throat, such as 

 ulceration, gangrenous change, and suppuration, which may be 

 accompanied by symptoms of general septic poisoning. The detec- 

 tion of the bacillus of Loffler in the false membrane or secretions 

 of the mouth is to be regarded as supplying the only certain 

 means of diagnosis of diphtheria. 



Bacillus Diphtherise. Microscopical Characters. If a film 

 preparation be made from a piece of diphtheria membrane (in 

 the manner described below) and stained with methylene-blue, 

 the bacilli are found to have the following characters. They are 

 slender rods, straight or slightly curved, and usually about 3 p. 

 in length, their thickness being a little greater than that of 

 the tubercle bacillus. The size, however, varies somewhat in 

 different cases, and for this reason varieties have been distin- 

 guished as small and large, and even of intermediate size. It is 

 sufficient to mention here that in some cases most are about 3 //. 

 in length, whilst in others they may measure fully 5 /x. Corre- 

 sponding differences in size are found in cultures. They stain 

 deeply with the blue, sometimes being uniformly coloured, but 

 often showing, in their substance, little granules more darkly 

 stained, so that a dotted or beaded appearance is presented. 

 Sometimes the ends are swollen and more darkly stained than 

 the rest; often, however, they are rather tapered off (Fig. 116). 

 In some cases the terminal swelling is very marked, so as to 

 amount to clubbing, and with some specimens of methylene-blue 

 these swellings and granules stain of a violet tint. Distinct 

 clubbing, however, is less frequent than in cultures. There is a 

 want of uniformity in the appearance of the bacilli when com- 

 pared side by side. They usually lie irregularly scattered or in 

 clusters, the individual bacilli being disposed in all directions. 

 Some may be contained within leucocytes. They do not form 

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