PENTOSURIA 



By F. BLUMENTHAL, Berlin 



Prior to the last few years all urine which gave a distinct and unquestion- 

 able reduction test was considered to contain sugar, and permitted us to con- 

 clude the presence of grape sugar; this view is no longer tenable. We know 

 now that a variety of sugars are found in human urine all of which react to 

 the recognized sugar tests (Trommer's, N"ylander's, the phenylhydrazin test). 

 Besides grape sugar we find milk sugar, which appears during the puerperal 

 period in a woman who has an abundant secretion of milk yet does not nurse 

 her child; this substance may persist in the urine for months post partum, 

 in fact as long as the secretion of milk continues. Here the differential diag- 

 nosis from grape sugar is accomplished very simply by the fermentation test ; 

 milk sugar does not ferment ivith yeasty while grape sugar does. Robinson 

 and Lepine, and also Eosin and Laband, have lately described cases of levulo- 

 suria which is characterized by its independence of the ingestion of carbo- 

 hydrates, and this condition may be recognized by the decided levorotatory 

 power developed during the fermentation test of the urine. Of less impor- 

 tance is the occurrence of maltose, which occasionally appears in the urine in 

 diseases of the pancreas, and the presence of which can scarcely be detected 

 even by the most delicate chemical methods. Of more importance are the con- 

 bined glycuronic acids and the pentoses. 



We refer here to the former substances because the combined glycuronic 

 acids may be considered as pentose-carbonic acids, C5H10O5CO2. Combined 

 glycuronic acids are found in the urine after the administration of numer- 

 ous drugs, especially such as contain the aldehyd and ketone groups (Neu- 

 bauer), and these may then be excreted in the urine in combination with gly- 

 curonic acid. Among the best known of these drugs are: morphin, chloral, 

 turpentine, menthol, antipyrin, etc. Glycuronic acid is also found in the 

 urine combined with indoxyl and with phenol. As some of the combined 

 glycuronic acids respond to the Trommer and Nylander tests, it may be of 

 importance in such cases— particularly with doubtful tests — ^to search for the 

 cause, and it is then not infrequently found that, at least in human urine, we 

 are dealing with a very decided indicanuria. If the patient who voids this 

 reducing urine has taken any drug, the supposition is natural that it has been 

 excreted as glycuronic acid and has thus caused the reduction. 



The urine coming from a case of pentosuria gives a distinct but somewhat 

 delayed reaction with Trommer^s test, and usually (as E. Salkowski first 



