384 APPENDIX 



forms of nucleo-proteid found in urine do not react to the test, while serum albumin 

 does. Thus where a positive nitric acid test is present, and no precipitate occurs 

 with this test, the proteid present is usually nucleo-proteid. 



For Heller's test, pour a small amount of nitric acid into a narrow test-tube 

 and, while holding the tube at an angle of about 45, superimpose a layer of the urine 

 to be tested, which is delivered drop by drop from a pipette and allowed to flow 

 down the side of the tube. 



This test can be converted into a quantitative one which is sufficiently accurate 

 for clinical purposes. It is based on the fact that a specimen of urine containing 

 0.003% f albumin will give a perceptible ring at the layering of the urine and acid 

 in two minutes. If the ring appears at once or in a few seconds the albumin con- 

 tent is greater. From the qualitative test an idea can be formed as to the amount 

 of albumin which the urine contains, a heavy ring forming immediately showing a 

 considerable albumin content. Probably the highest elimination of albumin is 

 found in chronic parenchymatous nephritis where it may run from i to 3%. In 

 an ordinary case of acute nephritis 0.5% would be an average content. 



Recently I have been using for both qualitative and quantitative albumin tests 

 the apparatus shown in Fig. 7. This is simply a five-inch piece of one- fourth-inch 

 soft glass tubing heated at a point 2 inches from one end, drawn out for about two 

 inches and bent to form a U tube with one end shorter than the other. This form 

 of tube enables one to perform two tests with the same column of nitric acid and is 

 easily cleaned and dried. They may be kept suspended around a glass tumbler's 

 rim. Taking up a small amount of nitric acid with a capillary bulb pipette it is 

 deposited in the capillary curve of the bent tube. This acid pipette should be 

 kept attached to the acid bottle. With a second pipette the urine is deposited in 

 the short arm of the U tube and the presence of albumin shows by a distinct ring 

 at the junction of urine and acid in the clear capillary tubing. The long arm will 

 serve for the introduction of a second specimen of urine for the albumin test. 



For quantitative test we dilute the filtered urine with one or more parts of nor- 

 mal salt solution according to the intensity of the albumin ring. A very convenient 

 way of making the dilution is with a graduated centrifuge tube. Make a one to 

 ten dilution of the urine, mix and draw up with a bulb pipette and deposit in the 

 short arm of the U tube. A distinct ring forms in 2 or 3 seconds. Pour off one- 

 half of the diluted urine and make up with an equal amount of saline. Deposit 

 this 1-20 dilution in the long arm. The ring forms in about a minute. With 

 further testing it is found that a one to forty dilution shows a perceptible ring in 

 just 2 minutes. This final and successful dilution multiplied by 0.0033 gives the 

 percentage of albumin in the urine (40X0.0033=0.13%). 



Should it be desired to determine the nature of the proteids present either in 

 urine or in exudates or transudates the following method is applicable. Determine 

 the percentage of total proteid by the method employed above. Then throw down 

 the globulins by the addition of an equal amount of a saturated solution of ammo- 

 nium sulphate, filter and estimate the proteid content of the filtrate. The differ- 

 ence between that and the total gives the percentage of globulin/ The filtrate is 

 now treated with 5% acetic acid until a precipitate of nucleo-proteid ceases to form; 

 the fluid is filtered and the clear filtrate (which should not show any turbidity with 

 a drop of 5 % acetic acid) is tested for its proteid content, which represents the 



