This hypertrophy, true or false, is generally transitory, and occurs chiefly in the early stages of the disease. When the swelling persists through the entire duration of the affection, it is usually the result of a cystic degeneration of the gland. The visceral disorders do not present any characteristic features; they indicate general atony and diminished vitality of the organism: small, compressible pulse, sluggish and painful digestion, and constipation. The course of myxedema is progressive, but interrupted by frequent remissions. If no appropriate treatment is instituted, the stock of ideas becomes diminished, the psychic inertia becomes extreme, and complete dementia is established; also the physical symptoms become accentuated and death supervenes either from cachexia or from some complication (pulmonary tuberculosis). · Treatment. It is possible to supply, to a certain extent, the deficiency caused by atrophy of the thyroid gland by the administration of the thyroid substance of animals (almost exclusively that of the sheep), either in the crude form or in the form of pharmaceutical preparations. The thyroid substance may be administered in tablets, pills, or capsules containing it, either in the fresh state or dried and reduced to a powder. The capsules of Vigier contain ten centigrams of the fresh gland; they may be administered in doses as high as six capsules per day without inconvenience. A glycerine extract of thyroid gland is also prepared and is known by the name of thyroidine. Finally, Baumann and Proos have extracted from the sheep's thyroid a substance, iodothyrine, which seems to be the active principle. This substance is "triturated with sugar of milk in such proportions that one gram of the mixture represents one gram of the fresh gland.” 1 Thyroid medication must be employed with great caution. Toxic symptoms are easily produced: acceleration of the pulse and respiration, headache, attacks of vertigo, and, in severe cases, a tendency to collapse. Therefore it is advisable to begin the treatment with small doses, which should be gradually increased, and promptly reduced or suspended entirely on the appearance of alarming symptoms. The mental and physical effects of thyrotherapy are very rapid. In a few days the cerebral torpor becomes less marked, the skin reassumes its normal aspect, and the other myxedematous symptoms become abated. § 2. CRETINISM. Cretinism may be defined as an arrest of somatic and psychic development dependent generally upon a goitre, and more rarely upon simple atrophy of the thyroid gland. The affection occurs endemically in mountainous regions, such as the Alps, the Rocky Mountains, the high plateaus of Himalaya, Black Forest, etc., and sporadically in most regions. Its etiology is not well known. Numerous factors are said to be capable of causing it: atmospheric humidity; 1 Briquet. Valeur comparée des Presse médic., 1902, No. 74. médications thyroïdiennes. certain geological compositions of the soil (cretinism occurs frequently in countries where the soil is composed of schistose clay or of streaked sandstone); poor quality of the water, which in the endemic sections is poorly aerated, deprived of iodine, and charged with calcium and magnesium salts; want; heredity. All these causes, the influence of which should be kept in view, probably only prepare the soil for the action of some specific agent still unknown. According to the opinion of Griesinger, "endemic goitre and cretinism are specific diseases produced by a toxic cause of miasmatic nature." This attitude certainly most nearly corresponds to the modern medical consensus of opinion and has at present the greatest number of adherents. In fact one cannot fail to note the similarity which exists between the etiology of endemic goitre and that of other endemic diseases of parasitic or, as Griesinger says, miasmatic origin, such as malaria. The symptoms of cretinism usually appear in early childhood. Sometimes the onset is acute, so that the destruction of the gland is accomplished in a few days. Such was the case reported by Shields,1 in which an acute thyroiditis caused the destruction of the thyroid gland and resulted in cretinism. Much more frequently the process is insidious, and it is impossible to ascertain the exact date of onset. The size of the goitre is variable. The swelling may be slight, scarcely perceptible, or so enormous as to completely disable the patient. Resulting usually from a degeneration of the thryoid gland, it becomes 1 A Case of Cretinism Following an Attack of Acute Thyroiditis. New York Med. Jour., Oct. 1, 1898. evident at about the sixth or eighth year of age and increases up to the time of puberty or even later. Simple atrophy of the gland is much less frequent and is seen chiefly in sporadic cases. Physically the cretin exhibits, in addition to the changes in the thyroid gland, the following symptoms: the stature is below the normal; the face is pale, puffed, or marked precociously with senile wrinkles; the pilous system is poorly developed; the mucous membranes are pale, anæmic, and thickened; the teeth are abnormal in shape and in implantation and subject to caries; puberty is retarded or even absent, and the cretin may remain infantile all his life. Psychically we encounter all degrees of idiocy and imbecility. It seems, however, that the cretin is less impulsive, more manageable, and more capable of emotional activity than the ordinary idiot or imbecile.1 The brains of cretins present no known specific lesions; asymmetry and various malformations of the hemispheres are frequent. 2 The treatment consists in thyroid medication, the results of which are the more perceptible the earlier it is instituted. 1 Bourneville. Progrès médical, 1897. CHAPTER XX. MISCELLANEOUS GROUPS (Continued). MENTAL DISORDERS DUE TO ORGANIC CEREBRAL AFFECTIONS. ALL the so-called organic cerebral affections, whether diffuse or localized, have an influence upon the psychic functions. The most important among those which have not already been considered are tumors, multiple sclerosis, brain abscess, and central neuritis. Tumors, when small and of slow growth, may give rise to no mental symptoms.. In other cases the mental state presents certain peculiarities which may aid in the diagnosis: Dupré and Devaux1 have found that "patients suffering from cerebral tumor present a peculiar state of mental depression and enfeeblement, which constitutes their dominant psychopathic note: this state is one of torpor, psychic dullness, and clouding of the intellect, to which may be added mental puerilism." Properly speaking these cases present no true dementia until the affection has reached its terminal period. According to the same authors 2 "the intelligence, though clouded, is, however, not destroyed. It responds to strong stimuli, to imperious injunctions; it is veiled, but nevertheless present, and not 1 Nouvelle iconographie de la Salpêtrière Tumeur cérébrale. 1901, Nos. 2 and 3, p. 51. 2 Loc cit., p. 8. |