180 



Medical Bacteriology. 



3) Occasionally micro-organisms (pseudo-diphtheria bacilli among others) are met 

 with that very closely resemble the Klebs-Loeffler bacillus and render a positive diag- 

 nosis doubtful. In such cases attention to following table will be helpful: 



1) Form 



2) Size 



3) Threads 



4) Grouping 



5) Involution forms 



6) Motility 



7) Stains 



a. Loeffler's methylen blue 



6. Gram 

 c. Neisser 



8) Spores 



9) Alkaline potato 



10) Sugar agar and gelatin 



stab cultures 



11) Neutral litmus milk 



12) Anaerobic cultures in H 



13) Nitroso-indol reaction 



14) Inoculation experiments 

 (Guinea pig subcutaneous) 



B. Diphtheriae 



Slender and of same diameter 

 throughout 



Average 1.2-2 M 



Not formed 



Parallel grouping more or less 



characteristic but do not touch 



Common 



Immotile 



Stains readily giving banded 



or polar stain 



Positive 



Characteristic stain with very 



young cultures, six hours. 



Absent 



Growth almost invisible 



Full length of stab 

 Acid reaction 

 Grows well 

 After 7 days 



Death 36-48 hours. 



B. pseudo-diphtheriae 



Thicker at center than ends, 

 plumper and shorter ami less 

 variable than B. diphtheriae 

 Averaging 1-1.6 /* 



Not formed 



Parallel but lie closer together 



Rare 

 Immotile 



Stains more regularly 



Polar stain rare 



Positive 



Not under 24 hours 



Absent 



Visible and cream colored in 2 

 days 



Only at upper part 

 Alkaline reaction 

 No growth 

 After 21 days 



Non-pathogenic 



PYOGENIC MICROCOCCI. 



1) Stained cover-glass preparations are examined and if micrococci are found make: 



2) Smear cultures, or better agar plate cultures and work up the colonies as they 

 appear. 



MONILIA CANDIDA (Organism of Thrush). 



The material is collected by removing a portion of the patches or membrane and ex- 

 amining it: 



1) Under the microscope in a drop of glycerine. 



2) Cover-glass preparations stained with carbol-fuchsin or Gram's method. 



3) By means of smear cultures on agar or blood serum, the resulting growth being 

 examined either in glycerine mounts or stained cover-glass preparations. 



REFERENCES, v. J. 95; S. 101. See also various texts under special organism. 



EXERCISE CVH. EXAMINATION OF SPUTUM. 



Definition. By this term is meant all of the material derived from the air passages 

 by the act of coughing or hawking. 



METHOD OF COLLECTION. For diagnostic purposes it is best collected in a salt- 

 mouthed bottle (about 2 oz. capacity) which has been sterilized. The morning sputum 

 is best and before being collected the mouth should be rinsed out with water. 



