188 MYXEDEMA 



persons are met with in isolated regions, and are particularly numerous in 

 certain localities, and inasmuch as the development and distribution of the 

 disease are apparently dependent upon the condition of the soil and the water- 

 supply of the district in which the cretins accumulate, we call these cases 

 " endemic cretinism." In other parts of the world they are only occasionally 

 met with, and we then speak of them as cases of sporadic cretinism. In these 

 cases as in myxedema there is an insufficient development, or an atrophy and 

 disturbance of function of the thyreoid gland. Hence we speak of them as an 

 athyreosis chronica, in contrast to the results produced experimentally in ani- 

 mals, or after loss of the thyreoid by operation in man in whom this state may 

 be called cachexia thyreopriva. 



Accurate observation and study of the cases belonging to this group show 

 that endemic cretinism is a condition of physical and intellectual degenera- 

 tion, which occurs only where there are local predisposing causes, and a degen- 

 eration of the thyreoid gland produced by these or going hand in hand with 

 them. The disease begins its development even in fetal life. Sporadic cre- 

 tinism, on account of its resemblance to myxedema of adults, is in early 

 life also designated as infantile myxedema. In these cases we find mental 

 weakness even to idiocy. Like actual typical myxedema, it is an occa- 

 sional afEection of the thyreoid gland with consequent loss of function, i. e., a 

 disease not limited to a definite region. The course of genuine cretinism, as 

 well as myxedema, is a very chronic one, lasting for decades, so that a cretin 

 may attain relatively old age provided he does not die of some intercurrent 

 disease. Cases of sporadic cretinism (infantile myxedema) have, as a rule, a 

 briefer duration of life, and if not ameliorated by treatment scarcely survive 

 the third, at most the fourth, decade. Cachexia thyreopriva runs a subacute 

 course, and unless relieved by medical aid terminates in death after a com- 

 paratively short time, at the longest four or five years ! 



THERAPY 



This is not the place in which to discuss the clinical symptoms of these 

 diseases ; that degeneration of the thyreoid gland is unquestionably the causa- 

 tive factor in all of them is the only circumstance important for us. This is 

 clear not only from the general correspondence of the external pathologic phe- 

 nomena, but, in particular,, from the results of therapy founded especially 

 upon the knowledge of the causal role of the thyreoid gland in these cases. 

 The results of thyreoid therapy have proven, a fortiori, that the common cause 

 ■ of these diseases is an absence of function of the thyreoid, by which, it may be 

 remarked in passing, they differ from goiter or struma. 



Properly speaking, in these cases we are dealing with a substitutiontherapy, 

 replacing the lost or deficient glandular secretion by the administration of the 

 glandular substance or its extracts. 



The surprising experiments of Schiff, previously mentioned, actually com- 

 pelled the application of these principles in the human subject, and Bircher 

 m 1890 by implantation of a human thyreoid in a woman with cachexia 

 strumipriva first succeeded in obtaining a curative result. Shortly after 



