OBESITY - PATHOLOGICAL ANATOMY AND PATHOLOGY.
Obesity may persist in the various phases of its development for a pretty long time, with slight changes in its symptom complex, until the gradual dissolution of the organism; or else, in less frequent cases, it leads to an early fatal termination, under a rapid succession of the symptoms. Hence the changes in the various organs will differ according to the stage of the disease and its symptoms, and while the first organic changes due to the increased deposition of fat are more mechanical, degeneration will develop later on with the prog ress of the nutritive and circulatory disturbances.
The most conspicuous alteration in general obesity is presented by the adipose tissue and tissues iuclosing fat. This alteration affects mainly the quantitative relations. The increased volume which may assume colossal dimensions ; the widening, the permeation and infil tration of the substance of the different organs by fatty tissue; the massive quantities of fat deposited in the panniculus adiposus and in the interior of the body, have already been mentioned, and when we come to the consideration of the changes in the several organs we shall revert to the proliferation of fat upon and within them. If we follow Toldt in assuming the existence of a preformed adipose tissue as an independent organ, beside the capacity of the connective-tissue cells for storing fat in hypernutrition and for changing into fat cells, we have to deal in general obesity on the one hand with an increase of the preformed adipose tissue, and on the other hand with a fatty tissue secondarily developed from the transformation of the connec tive-tissue cells into fat cells. The latter tissue spreads wherever connective tissue extends between the elements of the organs, espe cially where it penetrates from the surface. We have reason for the belief that the processes which do the most damage to the phy siological functions of the vital organs are chiefly caused by the latter.
It is an empirical fact that the reduction of fat in cases of con genital obesity is effected with the utmost difficulty, often only to a limited extent, and that relapses are very frequent or form the rule; while iu persons who have become corpulent only through excessive nutrition the reduction is not alone more easily attained but is also more lasting. In the latter cases we might be justified in assuming,
in accordance with our presupposition, that the preformed adipose tissue does not exceed the normal and possibly may be below it, while iu the former class of patients there is probably from the start an ab normally great amount of adipose tissue in which the liquefaction and combustion of the fat is brought about with greater difficulty than in a fatty tissue resulting from the absorption of fat by the connective tissue. Further anatomico-physiological investigations and experi ments with reference to this theory based on empiricism, which ex plains many phenomena in the pathology and treatment of obesity that are otherwise hard to understand, are still lacking.
In the histological elements also quantitative differences in the accumulation of fat may be demonstrated in various cases of obesity. In the adipose tissue observed in the plethoric form, which feels elastic, tense, and hard, the fat globules are large, greatly dis tended, the fat cells are completely filled with fat and transformed into roundish, oval, or more elongated vesicular formations, whose membrane or nuclei can no longer be clearly recognized. The inn cons or rather mucoid intermediate substance is sparsely developed, hardly demonstrable, so that the fat cells are closely packed and thus constitute a firm tissue which has a granular section even in the cadaver. Iii other cases of the more anemic and hydrimnic variety, with flabby, doughy masses of fat, the cells are less filled with fat, often only half as much as the other kind, and partly contain several larger and smaller drops of fat. Membrane and nucleus are also more distinctly demonstrable. The fat globules are small, loosely put to gether, and the intermediate substance is more abundant, saturated with sero-inucous fluid, and imparts to the tissue the characteristic doughy quality. The tensely filled adipose tissue has a more whitish or yellowish color, in the other less completely filled fat cells the yel lowish or reddish-yellow color is more pronounced. The differences in the external characteristics of the adipose tissue are due partly to the varying chemical composition of the fat, partly to the varying amount of coloring material present, and to the condition of the sur rounding tissue as regards bulk and arrangement.