THE CKETINIC DEGENERATION 451 



7. Frequent involvement of other ductless glands, particularly the 

 hypophysis and parathyroids. 



8. Failure to regularly obtain the excellent results which follow 

 thyroid therapy in sporadic hypothyroidism. 



The most plausible explanation advanced to account for these differ- 

 ences between endemic cretinism remains then in substance to-day the 

 same as first expressed by Ewald as early as 1896, who regarded the cre- 

 tinic degeneration as a chronic degeneration aifecting the organs in general, 

 also the thyroid gland. This view is held by most authorities at present 

 and has received additional support by recent experimental researches. 



Theories as to the Etiology of the Cretinic Degeneration 



The development of hypotheses and theories in regard to the pathogene- 

 sis of cretinic degeneration has paralleled the expansion of medical knowl- 

 edge in general. The older views attributed endemic goiter and cretinism 

 to a multitude of fantastic factors none of which can resist the light of 

 modern scientific investigation, although many are fraught with great 

 medical, historic and literary interest. It is surprising that so much 

 space has been given these hypotheses, even in modern text-books. 



The theories as to the pathogenesis of cretinic degeneration have been 

 ably presented by a number of writers on the subject. Among them, 

 Crotti in his recent work on "The Thyroid and Thymus" has critically 

 analyzed the various standpoints in a masterly fashion. In a work of 

 the present dimensions, it is only possible to give a brief summary of the 

 most pertinent material. 



The Relation Between Water Supply and the Cretinic Degeneration. 

 No single fact concerning the etiology of this disease is more firmly 

 established than the water-borne nature of the causative agent. The pro- 

 duction of goiter and cretinism by drinking from "goiter-wells," "goiter- 

 springs" and brooks has been known from antiquity. Newcomers into 

 a community using such water become goitrous, conversely the removal 

 from such a community is followed by diminution of goiter and cretin- 

 ism. The introduction of a pure water supply acts in a curative manner. 

 Of the many interesting examples quoted in the literature, two must 

 suffice. The account of E. Bircher (a) of the improvement taking place 

 in Rupperswil, a village of the Aargau, after the introduction in 1883 of 

 a new water system from a goiter-free locality has become classic. 



In the year 1885 there were 59 per cent of goitrous school children 



>? ?? 1886 " " 44 " " " " " " 



?? ?? ?? 1 S89 " " 25 " " " " 



" " " 1895 " " 10 " " " " 



99 1907 " " '2.5 ' " " " " " 



