88 DIABETES MELLITUS 



88 grams of sugar per day. If he lives for months, with this glycosuria, it is to be 

 expected that with the same nourishment he will excrete more sugar; for example, 4 

 per cent., that is, upon an average, 100 grams per day; in other words, his tolerance 

 (for carbohydrates) has decreased. 



This lessening of tolerance, due to the glycosuria, may not take place if 

 the glycosuria is very slight and does not amount to more than from ten to 

 twenty grams in a day; but in cases in which the glycosuria shows such an 

 increase as in the example just quoted, the patient's tolerance is bound to 

 diminish within a short time. 



Thk second fundamental PHiNCiPLE which is a necessary complement 

 to that mentioned above is as follows : 



When the diabetic is free from sugar, his tolerance usually increases. 



For example, a diabetic on the diet previously mentioned excretes 88 grams of 

 sugar. To diminish the glycosuria his allowance of bread is reduced; this decrease in 

 food, however, is not sufficient; bread must be withdrawn entirely to render the patient 

 free from sugar ; as soon as even ten grams of bread are allowed he begins to excrete 

 sugar again, although only from six to eight grams per day. Next the patient remains 

 for four weeks without bread and his urine becomes free from sugar. After this, if the 

 physician is careful, from twenty to thirty or forty grams of bread may gradually be 

 given without being followed by an excretion of sugar; the patient's tolerance, during 

 the sugar-free period of four weeks, has been materially improved. 



How may both these conditions be explained ? The improvement of toler- 

 ance during the sugar-free 'period exemplifies Hoffmann's law that " by lessen- 

 ing the work of any diseased function the latter may be improved," which law, 

 however, if we are honest, is, in the case of diabetics, little more than a lengthy 

 statement of the facts which are to be explained. 



There is more hope of success in the attempt to explain the aggravation 

 of the patient's intolerance of carbohydrates during every decided glycosuria. 

 The amount of sugar in the blood, as is well known, is quite constant in man, 

 at least it never falls below a certain point (about 0.8 per cent.) ; if, for exam- 

 ple, after severe muscular exertion, sugar almost disappears from the blood, 

 a fresh supply is sent from the carbohydrate storehouse (the liver) ; this 

 may be called a process of compensation. If now, after severe sugar losses, 

 it is desirable that a great amount of sugar be quickly brought to the blood, 

 it appears (according to some facts the explanation of which I shall not give 

 at this point) that a hypercompensation occurs. Hence arises the paradoxical 

 conception that loss of sugar produces hyperglycemia ! If this seeming para- 

 dox is really true, and if it holds good even for the diabetic with an already 

 existing hyperglycemia, then a spontaneous increase of diabetic hyperglycemia 

 by hypercompensation becomes comprehensible. Therefore, as long as sugar is 

 lost by the urine, a steady increase of hyperglycemia leading to a still greater 

 glycosuria is to be expected. 



Whether these attempts at explanation are correct or not, the two laws 

 themselves to which they refer are as near the truth, I think, as can be deter- 

 mmed to-day. And as the aim of the therapy of diabetes they show us this: 

 to render the patient free from sugar and to keep him aglycosuric. 



This conclusion is identical with that arrived at in the end of the last chap- 



