Observations in the valley of Aosta, where goitre is endemic. Conclusions: (1) all the examinations of Iva-ter used for drinking purposes by the subjects of endemic goitre revealed the presence of numerous bacteria; (2) the constant presence, in variable quantity. of a bacil lus which liquefies gelatin, and has spe cial morphological and biological charac ters; (3) this water, given to horses and dogs in a district exempt from goitre, produced an enlargement of the thyroid; (4) it is not yet proved that elimination of the microbes destroys the power of the water to cause goitre. Lustig and Carle (Med. Bull., July, '91).
The disease believed to be due to an organism of an amoeba type, and resem bling the malarial organism, with a se lective power for the thyroid or its secre tion. For a time the system opposes it, and sometimes successfully, but, when it overpowers the pha.gocytic resources of the system, the thyroid enlarges in the effort to combat the poison. Under thyroid feeding (two 5-grain tabloids daily) the records show a weekly dimi nution of a quarter to half an inch in the circumference of the Sepoy's necks, and when the treatment ceases the gland again increases in size. That is to say, additional resisting-power is adminis tered in the shape of thyroid tabloids, which keep the poison in check and allow the gland to recover its normal size, but on withdrawing the accessory agent there is diminished resistance and again an increase in size. E. E. Waters (Brit. Med. Jour., Sept. 11, '97).
1. The causation of simple goitre is directly associated with the water habitually drunk by the subjects of the condition.
2. No single constituent or contamina tion has so far, despite extensive search, been found common to the waters of goitrous districts.
3. The peculiar epidemics at times recorded, coupled with the lack of dis covery of chemical or toxic cause, ap pears to indicate miasmatic—i.e., micro bic—causation.
4. If it exists, the microbic agent is yet to be discovered.
5. A long series of forms can be made out from, on the one hand, those showing well-marked goitres with dulling of in tellect and bodily habit approaching to the myxcedematous type, through goitres presenting no generalized disturbance, save occasionally such as may be at tributed merely to pressure upon the surrounding organs, to other forms of ordinary goitre showing symptoms of the same order as those seen in exoph thahnie goitre, to cases of true exoph thalmic goitre, and, finally, to cases showing no enlargement of the thyroid, but certain of the general symptoms which are peculiar to Graves's disease.
Adami (Montreal Med. Jour., Jan., 1900).
The only two predisposing factors•that stand out at the present moment as likely to be predisposing are, indeed, altera tions in the sexual function and the na ture of the drinking-water. Attempts have been made, both in the Pyrenees and again in Michigan, to cure or arrest the onset of the condition by boiling or filtering the water. Kocher recommends the same. So far adequate evidence as to the effect of these measures is lacking.
Pathology. — To discuss at all ade quately the pathology of goitre, the minute anatomical differences between the various forms of goitre alone would take up far too much space. But there are certain points which must always be kept in mind. The first of these is the remarkable vascularity of the normal thyroid. As Councilman has pointed out, the size of the thyroid arteries is larger than that of those going to the brain. This, in itself, indicates that the blood-supply must be relatively enor mous, and that the functions of the gland must be relatively very important to the economy. The second is with regard to the nature of the secretion into the ves icles. The evidence at present before us would appear to show a close relationship between the lymphatics and the cavities of these vesicles. What that relationship is has not been adequately proved, but it would seem that the colloid material is formed by an inspissation and possibly a modification of the excretion from the epithelial cells lining the vesicles; and inasmuch as numerous observers have pointed out the presence of similar col loid material in the lymphatics in the immediate neighborhood of the vesicles, it is very possible that normally the lymphatics carry away the material elab orated by the cells. That this material is of importance to the organism has been abundantly demonstrated in the last few years by the researches of Baumann and Robert Hutchinson. The latter has con clusively proved that the albuminous col loid material carries or contains what may be termed the active principle of the gland, and that, if this colloid material thus isolated be given to myscedematous patients, it has all the good effects of the full extract of the gland. And he has shown that combined with it there is iodine; in fact, that Baumann's thyro iodine obtained from the whole gland is evidently the active albuminous sub stance in this secretion.