282 THE DUCTLESS GLANDS 



H. Diseases of the Thyroid 



Thyroiditis acuta, carcinoma, sarcoma, syphilis, tuber- 

 culosis, and echinococcus are all known, but apparently none 

 of these lesions give rise to any of those symptoms usually 

 associated with absence of thyroid function viz., myxoedema, 

 cretinism, etc. This seems to be the case even when gangrene 

 occurs. 



The diseases which will be referred to are (1) Goitre, (2) 

 endemic cretinism, (3) myxcedema, (4) cachexia strumipriva, 

 and (5) Graves's disease. 



1. Goitre 



The aetiology of endemic goitre is a long-standing puzzle, 

 and there are many aspects of the question which still remain 

 in obscurity. The distribution of the disease is so extra- 

 ordinary and so well known that it need not be described here. 

 It is now generally recognized that it is an infection due to a 

 living germ confined to certain geological formations, and 

 transmitted to man by means of drinking-water. 



McCarrison, from observations carried out in Gilgit, Kashmir, 

 concludes that goitre can be experimentally produced in man 

 by the administration of the matter in suspension separated 

 by filtration from waters that are known to be goitre-producing. 

 Goitre cannot be produced when the suspended matter is boiled. 

 The disease is due, therefore, not to mineral, but to the living 

 component of the suspended matter in other words, to a 

 living organism of disease. The incubation period of experi- 

 mentally produced goitre is usually about ten to fifteen days. 

 Goitre can be cured by the administration of intestinal anti- 

 septics. Thus the lactic -acid ferments exercise a curative 

 action when applied to the treatment of incipient goitres. It 

 is probable, therefore, that the organism which is the cause of 

 the disease is parasitic in the human intestine. The faeces of 

 most cases of goitre in Gilgit show a plentiful amoebic infection, 

 but whether the disease is due to this infection has not been 

 determined. The disease cannot be communicated to dogs 

 by means of extracts from the faeces of goitrous individuals. 

 Bircher finds that filtering does not destroy the contagion, 

 while boiling does. This theory of McCarrison has not been 

 universally accepted. 



