344 HEEMAN O. MOSENTHAL 



and Oppermann, Stilling, Tachau, Weiland(fr), Williams and Humph- 

 reys) it is very evident that the blood sugar in nephritis is increased in 

 some cases and not in others; this variability of the blood sugar occurs 

 apparently whether the nephritis is acute or chronic, whether it is of the 

 "parenchymatous" or "interstitial" type, whether or not it is accompanied 

 by hypertension, uremia, apoplexy or an increased blood urea ; further- 

 more, the following conditions, which may be considered as having some 

 relation to nephritis, show the same inconstancy in the blood sugar level, 

 eclampsia, essential hypertension, and arteriosclerosis. Williams and 

 Humphreys found the blood sugar in nephritis to be as high as 0.25 per 

 cent, Myers and Killian(a) (1917) 0.32 per cent and Mason 0.22 per cent 

 in acute nephritis. 



Some of the authors mentioned above have investigated this matter 

 further and have determined the changes occurring in the blood sugar 

 after the administration of given amounts of glucose. These "blood sugar 

 curves" were frequently prolonged and rose to levels above the normal; 

 however, some individuals with normal reactions were found. The sugar 

 in the blood in nephritis may therefore be regarded as having, in some 

 cases at least, the characteristics found in diabetes mellitus. 



A very puzzling feature about this abnormality is the fact that ap- 

 parently it bears no constant relation to the severity of the renal involve- 

 ment or to any one of the common complications of nephritis. It is worthy 

 of note that as the investigations concerning blood sugar progress, there 

 are a constantly increasing number of conditions in which it is found to 

 rise above the normal. The well known facts, that it is associated with, 

 an increased activity of the thyroid, suprarenal and hypophyseal glands, 

 experimental deficiency of the pancreas, and diabetes mellitus may be 

 cited; furthermore, recently similar blood sugar curves have been found 

 in some cases of syphilis (Rohdenburg, Bernhard and Krehbiel) and in 

 gastrointestinal cancer (Friedenwald and Grove). The occurrence of 

 blood sugar reactions, resembling those of diabetes mellitus, in so many 

 apparently widely different diseases, and the inconstancy of its presence in 

 nephritis or any of its more usual complications, make it very difficult 

 to assign a definite cause for it. 



An explanation of these blood sugar abnormalities has frequently and 

 somewhat thoughtlessly been attributed to a retention of glucose by the 

 kidney because of a raised renal threshold to this substance. Such a mode 

 of reasoning is obviously wrong, as the kidney ordinarily does not excrete 

 an appreciable amount of sugar and thus can not be responsible for its 

 increase in the blood; the cause for this phenomenon must be sought 

 in some metabolic disturbance which mobilizes the blood glucose with ab- 

 normal rapidity. 



Various other interpretations have been given. E. Xeubauer (1910), 

 in the original communication on this topic, suggested that it was due 



