G62 LEWELLYS F. BAEKEE 



Since the definite proof has been brought that the loss of function of the 

 parathyroid glands accounts for the origin of tetania strumipriva, there has 

 seemed to many good reason to believe that the other forms of tetany also 

 are due to loss, or to diminution, of the functions of the parathyroid glands. 

 When the parathyroid glands are not properly functioning, some poison, 

 they think, gets an opportunity to act upon and to injure the nervous sys- 

 tem, so that the symptoms of tetany appear. Just how the parathyroid 

 glands become insufficient, and just how the "tetany poison" gets the oppor- 

 tunity to work in forms of tetany other than tetania strumipriva, are prob- 

 lems that remain still, they admit, to be worked out. In other words, 

 though the general pathogenesis that they assume for tetany would seem to 

 have reached a satisfactory stage in the establishment of the doctrine of 

 parathyroid insufficiency as the pathological-physiological basis, it is 

 admitted by them that there is still room for extensive clinical and experi- 

 mental study before the precise etiology of the disease in its several forms 

 can become clearly understood. But to the more conservative, this view, 

 though interesting, need not seem final. The experimental production of 

 Tetany in man by forced respiration (vide supra) would make it seem pos- 

 sible that any condition that heightens the excitability of the nerves in a 

 certain way may be responsible for the occurrence of tetany. In the last, 

 analysis, may not this heightening of excitability depend upon the with- 

 drawal of calcium from the neurons, owing to either acidosis or alkalosis, 

 the latter conditions being producible by a variety of causes, of which para- 

 thyroid insufficiency is one and byperpnea another ? 



10. The Poisonous Substance in Tetany 



The phenomena of tetania strumipriva in man and the symptoms that 

 follow complete extirpation of the thyroid and the parathyroids in animals 

 have impressed many investigators as those of an acute intoxication of 

 some sort. The idea quickly arose that the symptoms might be due to some 

 form of auto-intoxication, dependent upon the removal of a "detoxicating" 

 organ. Some investigators assumed that the detoxicating organ is the 

 parathyroid, and that the intoxicating organ is the thyroid. But out of 

 accord with this view were the observations that a certain vicarious rather 

 than an antagonistic relationship appears, as we have already seen, to exist 

 between the thyroid and the parathyroids. The symptoms on complete 

 removal of both thyroid and parathyroids simultaneously are less marked, 

 according to Vassale and Generali, than those following parathyroidectomy 

 alone, and these authors assumed that the explanation lies in the removal 

 (in thyroparathyroidectorny) of the poison producing organ (the thyroid) 

 along with the detoxicating organ (the parathyroids). It has been asserted 

 by Van Calcar, also, that when the thyroid is not removed at parathyroid- 



