THE SPUTUM 133 



sputum from the lungs ; there is frequently nothing to dis- 

 tinguish it from that of other regions, and this is especially the 

 case when it is derived from a cavity which is lined with pyogenic 

 membrane. But sometimes the sputum contains very charac- 

 teristic alveolar epithelial cells. These are derived from the lining 

 of the alveoli, the cells of which lose their flattened shape and 

 become spherical in many pathological conditions. They are large 

 round or oval cells, much larger than the polynuclear leucocytes, 

 and have clear protoplasm and a round or oval nucleus, which is 

 often placed eccentrically. They are actively phagocytic, and 

 their contents give an important clue to the nature of the patho- 

 logical process at work in the lungs, since they are derived directly 

 from the alveoli. In pneumonia they may be seen to contain 

 pneumococci, and this is especially the case after the crisis ; in 

 congestion, and especially passive congestion, of the lung they are 

 packed with red corpuscles, often in various stages of destruction, 

 or with granules or crystals of altered blood-pigment. In diseases 

 due to dust the cells contain fragments of the dust in question, 

 but it must be remembered that particles of coal-dust are often 

 found in them in normal conditions in city dwellers. 



In asthma the characteristic Curschmann's spirals may be seen, 

 and the cells will be found to consist almost entirely of eosinophile 

 leucocytes. 



THE GASTRIC CONTENTS AND VOMIT 



The bacteriological examination of the stomach contents is not 

 of much importance except in one case — i.e., in the differential 

 diagnosis of carcinoma ventriculi and simple dilatation of the 

 stomach. For this purpose it is usually sufficient to examine the 

 vomit, or, if vomiting does not occur, the gastric contents removed 

 by a stomach-tube. It is quite unnecessary to give a test meal, 

 though this is advisable if a chemical examination is to be made ; 

 this should be done in all doubtful cases, but since the methods 

 requisite are outside the scope of this work, only a couple of 

 simple tests will be given. 



The examination is carried out quite simply by the wet method. 

 Two or three drops of the vomit (avoiding undigested food or 

 mucus, since the latter is likely to be derived from the mouth or 

 pharynx) are placed on a slide, and either examined just as they 

 are, or a drop of watery methylene blue, gentian violet, or other 



