HYPOTHYEOIBISM 381 



Hypothyroidism as here described may be said to include all conditions 

 due to defective thyroid function unaccompanied by the toxic symptoms 

 (tachycardia, exophthalmus, etc.) which also distinguish Graves' disease 

 'as well as Dysthyroidism, the clinical combination of thyrotoxic and hypo- 

 thyroid symptoms. Dysthyroidism is treated in a previous section. 



Hypothyroidism in its various sporadically occurring forms may fur- 

 ther be separated, if uncertainly at best, from the endemically occurring 

 Cretinic Degeneration described in the succeeding chapter. The latter 

 condition may at any time exhibit itself in clinical forms identical with 

 hypothyroidism as usually encountered, and has thus given rise to the 

 synonym Endemic Cretinism. Certain peculiar characteristics render a 

 separation from hypothyroidism advisable, so the term Cretinic Degenera- 

 tion (Falta) is preferred. 



As all clinical types of hypothyroidism described in the present chapter 

 have a common etiology defective or absent thyroid function it seems 

 inadvisable to perpetuate the confusion of the past by continuing to recog- 

 nize the overabundance of synonyms still in use. 



In this connection, the term goiter may first be discussed. The word 

 goiter simply refers to a state of hypertrophy of the thyroid gland. It may 

 be a prominent symptom of Thyrotoxicosis (Graves' disease). As the 

 first reaction to injury or failing function of this organ from whatsoever 

 cause, goiter may occur as a symptom of hypothyroidism. For this reason 

 so-called "simple goiter" is treated in. this section. Again, certain goiters 

 such as that of pregnancy may be regarded as very probably physiologic. 

 Difficulty has, however, arisen in regarding goiter as a separate clinical 

 entity, as has unfortunately been done in most older and some of the 

 latest text-books. 



The separation of the subject endemic goiter from endemic cretinism 

 by some authors seems, on the grounds just mentioned, inadvisable though 

 it is true that goiter may be the only striking symptom exhibited in some 

 communities suffering from the cretinic degeneration. 



For similar reasons "congenital goiter" is not separated as a topic in 

 this work from other symptoms of hypothyroidism. This viewpoint has 

 been adopted as McCarrison has succeeded in producing experimentally 

 congenital goiters accompanied by other unmistakable general organic 

 changes due to defective thyroid function. The term "toxic goiter" is at 

 times loosely used as a synonym for thyrotoxicosis. The term toxic goiter 

 is unfortunate as it may indicate both cause and effect, a goiter causing 

 toxic symptoms or a goiter produced by an existing toxemia. 



A number of writers on the thyroid gland have adopted the terms 

 "Athyreosis" and "Hypothyrosis" (Pineles) as a nosological classification. 

 Although the proof that athyroid individuals may exist is important, still 

 it seems ill advised to thus overemphasize this condition in view of the 

 fact that there are only about fifteen reliable cases of athyreosis on record 



