THE SYMPATHETIC SYSTEM 113 



nervous system, resulting from pyloric stenosis or other 

 intestinal affections, are sufficient to explain the tetany 

 manifestations without it being necessary to invoke the 

 action of the parathyroids. 



(d) The action of the parathyroids in the other types 

 of cases is doubtful and questionable. Histological exami- 

 nation in tetany of infectious origin in adults is missing. 

 In a tuberculous woman, developing tetany, Carnot and 

 Delion found a tuberculous caseation of one of the glands, 

 but were unable to find some of the other parathyroids. 

 Winternitz in 1905 published a similar report. 



When all is said, only the post operative forms of tetany 

 can be considered unquestionably to be due to parathyroid 

 insufficiency. Medical tetany, because of its similarity 

 to surgical tetany, has a possible parathyroid etiology, 

 but the anatomical reports and the results of organo 

 therapy do not allow us yet to confirm this possibility in 

 all the cases observed. 



How does parathyroid insufficiency determine tetany? 

 Two theories are suggested: 



1. CALCIUM THEORY. The observations of Loeb, 

 who in 1900 showed the relationship between neuro 

 muscular hyperexcitability with a decrease in the calcium 

 salts, then the experimental work of Frouin, Parhon and 

 Urechie, showing that the absorption of calcium chloride 

 after parathyroidectomy, prevented the appearance of 

 the nervous symptoms, have led us to believe that para- 

 thyroid insufficiency caused an excessive secretion of 

 calcium. The parathyroid glands regulate the metabol- 

 ism of calcium, just as the pancreas regulates that of 

 glucose. They have an inhibitory action on the excretion 

 of calcium. Tetany is a calcium diabetes. 



2. Toxic THEORY. According to Pfeiffer and Mayer, 

 Berkeley and Beebe the accidents of tetany are of a toxic 



