126 BIOLOGY OF PNEUMOCOCCUS 



BILE-SOLUTION OF SPUTUM 



In 1920 and 1921, Oliver 10256 reported a method by which the 

 precipitable substance of the pneumococci in pneumonic sputum 

 was brought into solution by bile and the filtered material then set 

 up against known antiserums. With incubation at 42° to 45°, 

 when the serum and the specific substance derived from the organ- 

 isms were of the same serological type, immediate clouding and 

 flocculation appeared, the whole procedure requiring only about 

 thirty minutes for completion. Checked against the mouse-protec- 

 tion method there was full agreement in the results obtained. 



The Oliver technique had advocates in Sharp and Urbantke. 1261 

 These authors in a study of forty cases found that when pneumo- 

 cocci of fixed types were intermingled with streptococci and Group 

 IV organisms, the presence of the former was often obscured and 

 identification difficult. The Oliver method appeared to be more suc- 

 cessful than the classic mouse method with such specimens. Direct 

 type determination of the infecting strain in pneumococcal menin- 

 gitis was rendered feasible by slightly modifying Oliver's scheme. 

 The sediment from centrifuged spinal fluids was treated with so- 

 dium taurocholate, the mixture shaken, and after being allowed to 

 stand, centrifuged at high speed. The supernatant fluid was then 

 mixed with type serums. A positive outcome was indicated by the 

 rapid formation of a precipitate. The procedure could also be car- 

 ried out on a microscope slide with equally definite results. 



Rosenthal and Sternberg 1175 proposed another rapid procedure 

 for type determination, which consisted in digesting sputum in a 

 borax-boracic acid solution and adding to the clear supernatant 

 fluid of the centrifuged mixture, in separate sections on a slide, 

 specific antiserums. The results by this method agreed in the ma- 

 jority of instances with those obtained by the mouse inoculation 

 test. 



Instead of utilizing the presence of precipitin as a therapeutic 

 control, Noble 1017 described a simple, though not particularly 

 original, method for determining the presence of agglutinins in the 



