CHAPTER XXVII 

 THE URINE 



MATERIAL -for staining is best obtained by centrifuging the urine, 

 then pouring off the supernatant urine, then draining the mouth of 

 the centrifuge tube against a piece of filter-paper so that we have only 

 the pus sediment to finally remove with a capillary bulb pipette or 

 toothpick stuck in a urine sediment pipette and make smears. 



I always take up the material with the centrifuge tube in a slanting position 

 following the draining off of the supernatant urine to avoid urine admixture in 

 the smear as such makes staining less satisfactory. The Gram staining is most satis- 

 factory, counterstaining with bismarck brown. 



The addition of a loopful of egg albumen or blood serum to about twice that 

 amount of urinary sediment gives better results. (See under Staining Methods.) 



In pathological urine there is enough albumin to fix the smear. 



The smear may be stained after fixing by heat with Gram's stain, T. B. stain, 

 or haematoxylin and eosin. The latter is the best for the staining of epithelial cells 

 and animal parasites; the Gram method for bacteria. 



It is frequently difficult to distinguish the spores of moulds from red blood-cells 

 except by measurement and staining reactions. Spores of moulds rarely exceed 

 five microns. 



Of the greatest value is the finding of phagocytized bacteria in the 

 pus cells of the Gram-stained smear. These indicate the causative 

 organism which show beautifully in the beginning of pyelitis infections. 

 To examine for epithelial cells I make a vaseline streak across a slide 

 about % inch from the center. A drop of the sediment is deposited 

 on the slide which may then be examined unstained with the % inch 

 objective and then a drop of Gram's iodine solution is added. One 

 edge of a square cover-glass is rubbed into the vaseline line and allowed 

 to drop on the fluid preparation. Currents are avoided and the cells 

 stain up beautifully. 



It is difficult to determine the presence of blood in urine in higher dilution than 

 i to 300 with the spectroscope. The ordinary occult blood test will show it in much 

 higher dilution. 



To secure urine for bacteriological examination catheterization is rarely necessary 

 in men in the case of women it is the proper method. 



393 



