334 EXAMINATION OF SPUTUM 



into a narrow V shape makes a very satisfactory rest for the slide in staining and is 

 convenient for the steaming of staining solution over the flame. 



Sputum should as a routine measure be stained by the Ziehl-Neelson method and 

 by Gram's method. 



In examining for tubercle bacilli it may be necessary to employ some method for 

 concentrating the bacterial content of the sputum prior to making the smear. A very 

 satisfactory method is that of Miihlhauser-Czaplewski. Shake up the sputum with 

 four to eight times its volume of 1/4% solution of sodium hydrate in a stoppered 

 bottle. When the mixture has become a smooth, mucilaginous-looking fluid, add a 

 few drops of phenolphthalein solution and bring the pink mixture to a boil. 



Then add drop by drop a 2% solution of acetic acid, stirring constantly, until 

 the pink color is just discharged. If the least excess of acid is added over that just 

 sufficient to cause the pink color to disappear, mucin will be precipitated. Now pour 

 this mixture into a centrifuge tube and smear the sediment on a slide and stain for 

 tubercle bacilli. 



Tubercle bacilli usually occur nested in clumps of sputum. There- 

 fore, when few in number it is only by chance that they may be found. 

 Concentration methods aim to dissolve these clumps of sputum and 

 collect, free from mucus, whatever bacilli may be present. There are 

 many concentration methods for sputum. One of these has been 

 given above. Uhlenhuth's method has some advantages over others 

 in the solvent used: i. It breaks up the sputum very rapidly; 2. it 

 immediately dissolves all organisms except acid-fast ones; 3. applied 

 in not too concentrated form and for not too long a time, tubercle 

 bacilli are not killed, so that by washing the sediment carefully by 

 several dilutions and centrifugings we have in the sediment viable 

 tubercle bacilli which we may attempt to cultivate upon Dorset's or 

 other suitable media with the reasonable hope that contaminations will 

 not choke them out or prematurely kill the inoculated guinea-pig; 4. 

 it has less effect upon the staining properties of tubercle bacilli than 

 any other material used in concentration methods. 



To make this solvent (antiformin) take double the quantity of chlorinated lime 

 and sodium carbonate required by the U. S. Pharmacopoeia and prepare according 

 to U. S. P. directions. To the finished liquor sodae chlorinatae (Labarraque's solu- 

 tion) add 7 1/2% of sodium hydrate. 



The Liquor sodae chlorinatae of the Br. P. is slightly stronger and some English 

 authorities recommend a mixture of equal parts of this Labarraque's solution and 

 r 5% sodium hydrate solution. As a rule one part of antiformin to five parts of 

 sputum is sufficient. Very tenacious sputum may require one part to four parts 

 of sputum. If more antiformin is used the specific gravity is too much increased 

 and the bacilli are damaged. The fluidification is hastened at incubator 

 temperature. 



To five parts of sputum add one part of antiformin, shake well and place in 



