Clinical Evidence relating to Hyperthyroidism 



37 



the enlargement is accompanied by hypersecretion which is the direct 

 cause of the symptoms, this opinion being founded on the facts that, (1) as 

 has just been mentioned, some of the symptoms of the disease can be 

 produced by excessive administration of thyroid, and (2) that the symptoms 

 are for the most part opposite in character to those which are known to 

 be produced by atrophy or diminution of function of the gland. Thus 

 there is a rapid and often irregular pulse ; nervous and psychical excitation, 

 with muscular tremors ; a feeling of warmth in the skin, and throbbing of 

 cutaneous vessels, often accompanied by profuse sweating ; shallow re- 

 spiration ; markedly increased metabolism (especially nitrogenous), with 

 abnormal appetite and loss of body fat ; 

 a decreased assimilatory power for carbo- 

 hydrates; an anxious, restless expression; 

 prominence of the eyeballs ; wide pal- 

 pebral aperture, often with dilatation 

 of pupils. The enlargement of the thy- 

 roid may involve only one lobe. The 

 enlarged gland pulsates, and gives a 

 murmur on auscultation. 



Exophthalmic goitre is far more 

 common in the female than in the male 

 (as 4'6 to 1), a fact which maybe related 

 to the enlargement of the gland which 

 usually occurs in the female at puberty 

 and during pregnancy. It is generally 

 associated with a persistent thymus, 

 which has by some authors been credited 

 with the production of certain of the 

 symptoms of the disease. About 13'5 

 per cent, of cases have polyuria without sugar. Only 2 per cent, have" 

 permanent glycosuria, although alimentary glycosuria is not uncommon. 

 Albummuria is present in about 11 per cent. 



The histological appearances (figs. 26, 27) are conformable with the 

 theory of a hypersecretion. The gland is greatly enlarged, and the indi- 

 vidual vesicles are irregular and tend to run together. The interstitial 

 tissue is increased in amount and assumes a lymphoid appearance, some- 

 times with characteristic germinal centres. The follicle wall tends to grow 

 into the interior of the conjoined follicles in the form of projections, thus 

 increasing the surface for secretion and giving the cavities a still more 

 irregular aspect. In some parts the follicles are smaller than usual, and 

 may even disappear. The cells lining the follicles tend to acquire a 

 columnar form : in later stages they may undergo degeneration and become 

 set free within the follicles. The contents of the follicles are more fluid 

 than in the normal thyroid, and in sections show little or no coagulated 

 colloid. 



FIG. 25.- Case of exophthalmic goitre. 

 (Byrom Bramwell.) 



