TETANUS ^g 



Examination of Pus from Suspected Cases of 

 Tetanus. 



Requisites. — i. Slides and cover-glasses. 



2. A stiff platinum loop. 



3. Bunsen burner or spirit-lamp. 



4. Loffler's blue or carbol thionin. 



5. Materials for Gram's staining. 



6. Balsam. 



If cultures are to be taken, add a pipette (see Fig. 14, b), a 

 deep tube of agar to which 2 per cent, of grape-sugar has 

 been added previous to sterilization, a flask of water, and a 

 thermometer. 



Method. — Scrape the deeper portions of the wound with the 

 platinum loop, and spread out the secretion thus obtained on the 

 surface of a slide. Prepare several of these slides, and fix the 

 film by heat. Stain some by the simple stain for two minutes 

 and others by Gram's method. 



The bacillus of tetanus is about as long as the tubercle bacillus, 

 and is very slender. It stains by Gram's method. A very 

 characteristic feature is its method of spore-formation. The 

 spores are spherical bodies which are formed at the extremities of 

 the bacilli, giving them the appearance of pins or drumsticks. 

 The spores do not stain by the ordinary stains, and appear as 

 colourless and highly refractile bodies (Plate II., Fig. i). 



The cultures are made in agar to which 2 per cent, of grape- 

 sugar is added, and the needle or pipette used in making the 

 inoculation is plunged deep down into the medium. The bacillus 

 of tetanus is an anaerobe — i.e., it grows only in the absence of 

 oxygen. The stabs are made deep in order to inoculate the 

 material far away from the air, and the glucose is added to absorb 

 any oxygen which may be in the medium. To increase our 

 chances of obtaining this bacillus in pure culture, the material 

 to be examined is to be heated to a temperature which will kill all 

 developed bacteria, but which will not be injurious to spores ; the 

 tetanus bacillus is the only anaerobic organism with a spherical 

 terminal spore which is at all likely to occur in a wound. 



Method. — The inoculations are to be made with a pipette. If 

 the pus which comes from the wound can be drawn up into the 

 capillary tube of a glass pipette such as is described on p. 34, 

 the material should be collected in this way. If this is not the 



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