In hydiwmic anemia there is a swelled condition of the eyelids, face, and lips; sometimes of the extremities; but rarely of other parts of the body. The tempera ture is normal; the bony system is per fect; there is no macroglossia, no altera tion in hair or skin, no obliteration of bridge or nose; no mental defect. Kop lik (N. Y. Med. Jour., vol. lxvi, No. 10).
Etiology.—All forms of cretinism de pend on absence or atrophy of the thy roid gland, or upon some disturbances of its function. But we are as yet in igno rance as to those causes which produce atrophy, or as to what the exact func tions of the gland are. Non-existence of the gland as a congenital affection has been demonstrated in a few cases of cre tinism. Sporadic cretinism may occur, as far as we yet know, in any land; cases have been reported all over Europe and in this country.
Clinical summary of 60 cases observed in the United States by various au thors:— Sex: Males, 24; females, U.
Age: Under two years, 6; from two to five years, 12; five to ten years, 12; ten to fifteen years, 10; fifteen to twenty years, 7; twenty to thirty, 3; thirty to forty, 4; over forty years, 4.
Nationality: American, white, 12; col ored, 1; Polish, 2; French, 1; German, 5; Swede, 1; IIebrew, 1; Norwegian, 1; Irish, 7; English, 1; Swiss, 2; Bohe mian, 1; nationality not given, 23.
Locality: There is no region in the country in which the disease is endemic, nor does it appear to be more prevalent in those districts, as in Michigan and parts of Ontario, where goitre is com mon.
Condition of the thyroid gland: Goitre was present in 7; gland stated to be normal in 12 ; gland small in 2 ; gland not to be felt in 16; no note in 20. William Oiler (Amer. Jour. Med. Sci., Oct., '97).
The endemic form probably occurs only in mountainous regions, and usually in the valleys between the mountains; it is endemic in parts of Switzerland, Italy, France, India, South America, Central America, and Mexico. In the United States and Canada this form is unknown, and it is never seen in low lying countries or on the sea-coast. Goitre is prevalent where endemic cre tinism occurs, and the two affections bear a definite, though unknown, relation to each other. Baillarger says: "Endemic cretinism never exists without endemic goitre." In localities where goitre among human beings exists, it is also found to be prevalent among animals, especially among mules, but also among dogs and goats.
[The idea has long existed that the drinking-water in these mountainous re gions was the cause of both goitre and endemic cretinism, and that they were due to either chemical or physical prop erties of the water, but Combe (Revue Mad. de la Suisse Romande, Anno xvii, Nos. 2 to 6) thinks that experiments have proved that the maladies cannot be attributed to either of these proper ties, but that the cause is a living micro organism. He says that ''goitre, and consequently cretinism, is an infectious disease, caused by a microbe, and that the microbe produces an hypertrophy of the thyroid, as others produce an hy pertrophy of the spleen, kidneys, etc." He thinks that it is not always due to the drinking-water, but that the microbe may be "air-borne." Virchow also thinks air a possible means of infection. He and Rabuteau believe that goitre is the result of the feeble action of a noxious principle, and cretinism that of a strong and prolonged action.
Bonchardat and llireher think that goitre is the first stage of cretinism. Air-infection might account for the epi demic which occurred in Somersetshire, England, in 1847; no cases are to be found there now. Combe gives an in teresting account of an epidemic of goitre which occurred in Lausanne; and his study of these cases leads him to be lieve that not only is air an important factor in the causation of the disease, but that the affection is also contagious.
Mendel (Deutsche med. Woch., p. 101, '95) suggests that the function of the thyroid is to secrete a substance which, when present, prevents the formation of or neutralizes, if formed, certain toxic substances. If the thyroid material be wanting, these hypothetical toxins ac cumulate and excite the symptoms al ready named.
Paterson (Lancet, ii, 849, '97) expresses his views in the following manlier: "The first theory is that the gland secretes some substances which is essential to the healthy and harmonious working of the central and peripheral nervous systems. By the want of this substance the nerv ous mechanism is deprived of a some thing which regulates the formation and deposition of mucin products, so essential a feature of both diseases (sporadic cre tinism and myxmdema), the mucin be ing thus deposited in the superficial and finer meshes of the corium, impairing motility and impeding nervous influ ences, afferent as well as efferent. The
second theory is that the thyroid gland excretes from the blood some materials formed in the body-metabolism, which by their retention cause a form of tox trmia, affecting principally the cerebral centres and the nervous mechanism con cerned in mucin metabolism." Combe (Revue Mad. de la Suisse Romande, Anno xvii, Nos. 2 to 6) sets forth a new view. He says: "Not alone the material antitoxins, but also the toxins, pass through the placenta. The child, as a result, would run a risk of being continually intoxicated, not only by its own toxins, but by those of its mother, if lie did not possess a powerful anti toxic gland. What is the object of the thymus if not to accomplish this im portant task? The thymus is a powerful antitoxic gland, and a gland antitoxic for albuminoid toxins, like the thyroid, since cases of myxcedema have been treated and cured with the thymus given in sandwich. Now, the cretin, whether he has a goitre or an atrophied thyroid, is born with a non-atrophic thymus. It is thus the active principle of the thymus which supplies the absent thyroid antitoxin, but as the thymus atrophies, as its active principle dimin ishes, poisoning manifests itself, and as a consequence cretinism develops. If the child is born a cretin it is probable that atrophy attacked the thymus as well as the thyroid: a fact which it is necessary to verify. This hypothesis is all the more probable, as Marie observed a case of congenital myxcedema in which the thymus was hypertrophied." From this he concludes that "the thyroid is an antitoxic gland whose function is to destroy, or modify, either by rendering innocuous or useful, some toxic sub stances resulting from the digestion of certain albuminoid bodies." Moussu (Comptes-Rendus Hebdom. des Seances de ]a Soc. de Biologie, 2, S., vol. iv, No. 2, '97) and Brissaud (La Presse Med., vol. i, No. 1, '95), on the other hand, do not believe that all the conditions seen in cretinism are due to the thyroid alone, but are also largely dependent on the parathyroid glands. Moussu draws deductions from experi mental evidences which, he believes, prove that the two glands have two distinct functions—the suppression of the thyroid causing only chronic disturb ances, that of the parathyroid provoking acute accidents; that death almost al ways follows extirpation of the latter, while disease alone is the result of ex tirpation of the thyroid. The 'Darn thy roids hypertrophy after removal of the thyroid. Brissaud from clinical evidence alone draws similar inference with regard to the difference of function of the two glands. He says "without doubt neither the structure nor the functions are the same, but it appears evident that very early in life they may replace each other ("Welles se c2 l'origine"); and if. at a given moment, they are specialized so as to fill two absolutely different roles, and possibly antagonistic ones, the simplest may, in a measure, take the place of the more complex and highly developed; in short, to take up both rules, should it so happen. The human thyroid gland, if this is the case, would represent a perfected parathyroid with delicate epithelium ("perfeetionnee 4 epithelia, fragile"), but still preserv ing among its new elements the old parathyroid epithelium, more worn ("fraste"), more resistant, and more durable. . . . In any case, however, it seems to me incontestable that the thyroid myxcedema, to speak accurately, is that form which is not complicated by intellectual apathy, and that para thyroid myxcedema is that.form which, resulting from a total alteration of the glandular structure, expresses itself not only by the characteristic infiltration, but by the arrest of development in the cretinoid idiot, or by the brutishness of cachexia strumipriva." Magnus Levy (Verhandlungen des Congresses f. innere lied., Wiesbaden, believes that cretinism in all its various forms depends on a perverted function of the thyroid, whether that be an increased or a lessened one. In four cases which he studied lie found a dimi nution in the consumption of oxygen and formation of carbon dioxide, whereas in Graves's disease it has been more than once proved that there is a marked increase in the consumption of oxygen and the formation of carbon dioxide.