Disturbances of Carbohydrate 



Metabolism, Other than in 



Diabetes Mellitus 



ISIDOR GREENWALD 



NEW YORK 



Introduction 



Diabetes mellitus is the great disorder of carbohydrate metabolism. 

 But there are several other conditions already known and, possibly, more 

 that are yet to be discovered in which there is a partial or complete failure 

 to oxidize certain carbohydrates. As with diabetes, these conditions are 

 generally recognized by the appearance, in the urine, of a substance 

 capable of reducing alkaline copper solutions. Though these conditions 

 may be relatively infrequent, it is important that the possibility of their 

 occurrence be kept in mind, so that patients should not be distressed by 

 the belief that they have diabetes when, in reality, their disorder is quite 

 different, generally of much less importance, and often quite harmless. 

 There have been several reported cases in which the patient has undergone 

 long, burdensome and expensive treatment for diabetes but in which 

 only the innocuous pentosuria existed. The number of unreported and 

 undiscovered cases is probably much larger. 



It is, of course, equally important that a mild diabetes be not mistaken 

 for pentosuria, or similar disorder, and consequently neglected and per- 

 mitted to develop into a severe type of the disease. 



An abnormality in the katabolism of carbohydrate may, conceivably, 

 involve : 



1. A complete or partial failure to utilize one or more carbohydrates. 

 In such case, these might be expected to appear in the urine. 



2. A similar failure to oxidize, not the carbohydrate, but one or more 

 intermediate products of its katabolism. This condition might manifest 

 itself in the appearance of these substances in the urine and, possibly, in 

 the expired air. A change in the value of the respiratory quotient might 

 also be observed. 



3. The occurrence of an abnormal path of katabolism. If the end- 

 products of such abnormal katabolism were also carbon dioxid and water, 



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