The full-blown expression of hypothyroidism is known as myxedema. Adult myxedema escaped serious attention until Gull described it in 1874 1 . That it was a state resembling the familiar endemic cretinism, but coming on in adult life, was what chiefly impressed Gull. Ord 2 invented the term myxedema in 1873. The disorder arising from surgical removal of the thyroid gland (cachexia strumipriva) was described in 1882 by Reverdin 3 of Geneva and in 1883 by Kocher of Berne 4 . After Gulls description, myxedma aroused enormous interest, and in 1883 the Clinical Society of London appointed a committee to study the disease and report its findings 5 . The committees report, published in 1888, contains a significant portion of what is known today about the clinical and pathologic aspects of myxedema. It is referred to in the following discussion as the Report on Myxedema. The final conclusions of the 200-page volume are penetrating. They are as follows:

1. That myxedema is a well-defined disease.

2. That the disease affects women much more frequently than men, and that the subjects are for the most part of middle age.

3. That clinical and pathological observations, respectively, indicate in a decisive way that the one condition common to all cases is destructive change of the thyroid gland.

4. That the most common form of destructive change of the thyroid gland consists in the substitution of a delicate fibrous tissue for the proper glandular structure.

5. That the interstitial development of fibrous tissue is also observed very frequently in the skin, and, with much less frequency, in the viscera, the appearances presented by this tissue being suggestive of an irritative or inflammatory process.

6. That pathological observation, while showing cause for the changes in the skin observed during life, for the falling off the hair, and the loss of the teeth, for the increased bulk of body, as due to the excess of subcutaneous fat, affords no explanation of the affections of speech, movement, sensation, consciousness, and intellect, which form a large part of the symptoms of the disease.

7. That chemical examination of the comparatively few available cases fails to show the general existence of an excess of mucin in the tissues adequately corresponding to the amount recorded in the first observation, but that this discrepancy may be, in part, attributed to the fact that tumefaction of the integuments, although generally characteristic of myxedema, varies considerably throughout the course of the disease, and often disappears shortly before death.

8. That in experiments made upon animals, particularly on monkeys, symptoms resembling in a very close and remarkable way those of myxedema have followed complete removal of the thyroid gland, performed under antiseptic precautions, and with, as far as could be ascertained, no injury to the adjacent nerves or to the trachea.

9. That in such experimental cases a large excess of mucin has been found to be present in the skin, fibrous tissues, blood, and salivary glands; in particular the parotid gland, normally containing no mucin, has presented that substance in quantities corresponding to what would be ordinarily found in the submaxillary gland.

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Adult Hypothyroidism - Thyroid Disease Manager