ALBUMINURIA. 179 



ditions, after some poisons, and in some infectious dis- 

 eases, the kidneys in any of these cases not being neces- 

 sarily in a pathological state. Severe muscular labor may 

 cause the temporary appearance of albumin. The quantity 

 present varies greatly under different conditions, and is 

 not necessarily a measure of the severity of the disease. 

 Still comparative tests in the same case will indicate some- 

 thing of its progress. 



The amount of albumin in the urine can be deter- 

 mined accurately by precipitating, drying, and weighing, 

 but the process is a long one for clinical purposes. For a 

 practical test, sufficient to show the variation in amount, 

 Esbach's method can be used. This depends upon precipi- 

 tating the albumin with a solution containing 1-per-cent. 

 picric acid and 2-per-cent. citric acid. The operation is 

 performed in a graduated test-tube, called an albuminom- 

 eter, the height of the precipitate indicating its amount. 

 Variations in temperature greatly affect the height of the 

 precipitate; consequently in comparative determinations 

 the conditions of temperature must be always the same. 

 The results are most accurate when not more than 4 

 grammes of albumin are contained in a liter. 



A more accurate method for the determination of the 

 amount of albumin in urine is to weigh it after coagula- 

 tion. Filter it if it is not clear, then drop in two or three 

 drops of very dilute acetic acid and heat to boiling. Filter 

 on a filter which has been weighed after drying at 100, 

 and wash with warm water first, then with alcohol. Dry 

 at 120 until its weight is constant. For exact results the 

 precipitate and filter must be burned, and the weight of 

 the ash subtracted to get the true weight of the coagulated 

 protein. If globulin is present it will also be found in the 

 precipitate with the albumin. 



