360 CYTODIAGNOSIS 



serum for various pyogenic bacteria and, if tuberculosis is suspected, inoculation 

 of a guinea-pig is indicated. 



The interpretation of cellular sediments is more difficult than many books would 

 indicate, there being many factors which tend to complicate the findings. 



The polymorphonuclears in purulent fluids often show fatty degeneration, 

 swollen and faintly staining nucleus or a breaking up of the nucleus into small deeply 

 staining masses (nuclear fragmentation). Such fragments in the smear may be con- 

 fusing. The endothelial cells often show fatty degeneration in the cytoplasm and 

 we often note bacteria and other cells which have been phagocytized by them. 

 Where proliferation of endothelial cells is going on actively the cells show a rather 

 deeply staining cytoplasm as compared with the light staining cytoplasm of the cells 

 in transudates. 



The following are the leading differentiations: 



1. A smear showing almost entirely lymphocytes with a few red 

 cells and very rarely a polymorphonuclear indicates a tuberculous 

 process. 



2. Where a pyogenic process is engrafted on a tuberculous one, we 

 have still the red cells, some degenerated lymphocytes, and in particular 

 polymorphonuclears showing fragmentation of their nuclei. 



3. When a hydro thorax results from chronic heart or kidney disease, 

 the characteristic cell is the endothelial cell, which greatly resembles a 

 large mononuclear. These cells often are arranged in plaques. 



4. Some authorities consider that the cancer cell can be recognized 

 by its occurring in masses and having a markedly vacuolated cytoplasm. 

 It has been claimed that they contain glycogen by which means we can 

 distinguish them from endothelial cells which they so much resemble. 

 If such cells should show mitosis the finding would be suggestive. 

 For mitotic figures wet fixation with some bichloride fixative, with H. E. 

 staining, is best. 



Jousset introduced inoscopy as a means of diagnosing tuberculosis. The fluid 

 was allowed to coagulate and was then digested with an artificial gastric juice. The 

 digested material was then centrifuged and the sediment examined for tubercle 

 bacilli. This process does not seem to have met with much favor in this country. 

 (Using sodium citrate obviates the necessity for digesting the coagulum.) 



The same points will hold for ascitic fluid as for pleural fluid. 



In taking cerebrospinal fluid for culture and cytodiagnosis we use a stout anti- 

 toxin needle without attaching a syringe. Aspiration is responsible for many of 

 the ill effects of lumbar puncture. The needle should be about 4 inches long for an 

 adult. Sterilize the skin and needle as described for blood cultures from a vein. 

 To make a lumbar puncture, place patient on left side with knees drawn up. A line 

 at the level of the iliac crests passes between the third and fourth lumbar vertebrae. 

 Select a point midway between the spinous processes of these lumbar vertebrae and 



