The so-called inherited cretinism, as a rule, is congenital; that is, acquired during foetal life. The injury of the thy roid gland and the pathologico-anatom ical substratum are the same as in cre tinism, which develops later. But the injurious material is absorbed by the mother from without, and by her is transferred to the thyroid gland of the fcetus. The overruling factor, then, is always the influence of the land upon which the mother lives. So long as the child is in embryo, its tissues, the pro vision and nourishment, as well as the disposal of waste-products, are cared for through the maternal blood. If, there fore, the thyroid gland of the child does not develop, or becomes atrophied through disease, the gland of the mother acts perfectly, both for herself and the child; so that the body of the child, at the moment of birth, will not show any more cretinic degeneration than that of the mother herself. If the latter have only a goitre in a thyroid gland in a normal portion of which the functions are still satisfactory, the child, at birth, will be plump and well shaped. It is only when the child, independently of the mother, begins to nourish its own nervous system and with it the thyroid gland, that, as in acquired cretinism, the disturbance begins gradually to appear. Koeher (Paris Correspondent Boston Med. and Surd. Jour., June 24. '97).
There is still one point to be con sidered with regard to the etiology of this disease, and that is the part played by "iodothyrin," or "thyro-iodine," as it was first known. In 1895 Baumann (Hoppe Seyler, Zeitsehrift f. physiol. Chemie, '95) demonstrated the existence of free iodine in the normal thyroid gland. It exists there in very minute amount, and there is less in the glands of children than in adults, and less in diseased glands (goitres) than in healthy ones. He later extracted the body "iodothy rin," which he believes to be the active principle of the gland; but it is doubtful whether this is the pure active principle; and, even were the cretinoid condition due to lack of formation of iodothyrin in the human body, we would still be in ig norance as to the primary cause of dis ease of the gland. Therapeutic use of iodothyrin has shown that both eases of myxcedema and parenchymatous goitres do improve under its administration; and that in sufficient doses it will pre vent the development of the well-known symptoms, which occur in dogs, from which the thyroid gland has been experi mentally removed.
Cretinism is relatively much more fre quent in children than was formerly supposed. It passes oftentimes unrec ognized. Koplik has pleaded most ear nestly for its recognition. Heredity seems to be a factor in the adult form. but this has not been determined in the child. There is a growing opinion as to its infectious nature, but no very posi tive data have been obtained. The in
terdependence of nervous control over secretion is recognized as necessary to healthy functionating, but it is not cer tain whether disorder of such control is the cause. The process is a slow delay of the bony development of the body and a consequent dwarfism. (Englemaun.) The importance of combining the dif ferent glands in the treatment empha sized. Many of the unsatisfactory re sults of glandular treatment are because the case is treated in only one direction. After having seen that a single ductless gland has been given without results a combination with other glands should be made. As a rule. thyroid feeding will be sufficient for myxcedematous condi tions. Another point is a shortening of the cranium, producing, as a result, a synehondrosis of the bones. Many of these are due to rickets which runs its course before birth. When the child is born there is a shortening of the bones at the base of the cranium because of the ossification of the occipital and sphenoid. The cases that have a short base of the cranium will be improved the least. (A. Jacobi.) It is in this class of cases that pre ventive medicine might achieve its most brilliant results. The term athyria em ployed by the author should be used to designate functional athyria, and not anatomical athyria. (David Riesman.) The combination of the pituitary with the thyroid showed quite a difference in the growth of the patient. (Engle mann.) Proceedings Amer. Med. Assoc. (Med. News, June 21, 1902).
Pathology.—Whether all the patho logical findings in sporadic and endemic cretinism are identical is a question still sub judice, but the later studies seem to show that there is no essential difference between them, and that the earlier drawn distinctions are not sufficient to separate them. Virchow was the first to state that the brachycephalie skull was typical of the endemic cretin, and was due to a premature synthesis of the os basilare, and the sphenoid, posticus, and anticus. This produces flattening of the bones at the root of the nose, and gives the peculiar expression to the cretin. His deductions were drawn from a single case, and it has since been shown that the brachycephalic type of head is not characteristic, but that the skull may be flattened, round, or pointed (platy-, tropho-, or oxy- cephalic). It thus ap pears that no type of skull is typical of cretinism.
Another distinction has been made be tween endemic and sporadic cretinism, and that is that in the former the fon tanelles close early, in the latter may remain open for a long time; but the significance of this difference is not yet appreciated or understood. The most interesting abnormal conditions seen in this disease pertain to the thyroid gland, the long bones, and the skin.