Page:Encyclopædia Britannica, Ninth Edition, v. 18.djvu/399

PATHOLOGY 377 leucocytosis or pseudo-leucocythsemia. The difference is even dis coverable, according to Virchow, in the morphological character of the colourless corpuscles in the two cases. In true leukaemia (splenic) the corpuscles in the blood are somewhat large, with multiple nuclei, and more rarely with a single nucleus ; in the pseudo-leukaemia (lymphatic) the cells are small, the nucleus single and large for the cell, the cell - substance being often so narrow a zone as to be hardly appreciable around the nucleus. These are practically the differences between the cells of lymph -glands or follicles and the residual nuclei of hfematoblasts (or pus-cells). This pseudo-leukaemia connects, on the one hand, with Hodgkins disease, a general condition of lymph-gland overgrowth, and, on the other hand, with solitary lymphomatous tumours, such as grow, mostly perhaps, in children in the kidney, or in the follicular tissue of the intestine, or elsewhere. Pernicious Aneemia. This is another serious and generally fatal error of blood-making, which presents both an instructive parallel to leucocythaemia and an instructive contrast. The onset of this disease is often sudden, it may be with symptoms of chills and heats and other febrile manifestations. It occurs at all periods of life, and in both sexes. The body seems to become strangely blood less, so that even the point of the finger will not bleed if cut. There is much listlessness, often giddiness, tendency to haemorrhages, especially into the retina, and pains in the bones. Recoveries, temporary or permanent, are more usual than in leucocythaemia, especially under the administration of arsenic. The blood is pro foundly altered, and the state of it may vary much within a space of weeks or even of days. The red disks are enormously reduced in number, and many of those that are left have departed from the usual type ; they may be either very large or very small, two or three times larger than usual, or two or three times smaller. Some of them are oval and flat, and sonic of them pear-shaped vesicles (fig. 41). They may have also an in creased colouring power, which means an undue concentration of haemo globin. When the two chief blood-making tis sues are investigated in such cases after death they do not always fur nish a rational explana tion of the state of the blood. It is, in fact, somewhat rare to find anything elucidative in the state of the spleen, and the interest is thrown mostly upon the bone- marrow Not always, but very often, this tissue is profoundly altered ; even the yellow marrow of the long bones is red or jelly-like, few or no fat-cells are visible, red blood-disks are everywhere, along with granulation-like marrow- cells, in a fine reticulum, and traversed by blood -sinuses which have been compared to the sinuses of the spleen. Sometimes the nuclear cells of the marrow are found with a zone of reddish pro toplasm round them or in the state of perfect hsematobksts. In this peculiar disorder of the blood-making process the salient facts appear to be the following. Red disks are formed from hfemato blasts with difficulty ; they are mostly either much too large or much too small ; the haemoglobin is too concentrated in them ; the bone -marrow makes quite unusual haematoblastic efforts; but the vessels at large remain ill supplied with blood, while the marrow itself is everywhere full of blood, and sometimes even tends to or ganize itself into a structure like the spleen. Degeneration follows in the muscular structure of the heart and in the walls of blood vessels ; to the former are owing some prominent symptoms, and probably to the latter the haemorrhages. One of the most singular things in this remarkable disease is the power of recovery, either temporary or permanent, that the organism may acquire, chiefly under the stimulus of arsenic. As compared with leucocythrcmia the striking fact is that the part played by the colourless corpuscles is from first to last a subordinate and even unrecognizable one. Scurvy. ^Scurvy. In scurvy we have a blood-disease of a kind somewhat different from leucocythaemia and pernicious anaemia, inasmuch as it depends, not upon unaccountable and seemingly capricious errors in the blood-making tissues, but upon errors in the ingesta, upon well -understood defects of diet. (See SCURVY. ) Irregular Irregularities of Blood -distribution. While the facts of blood- Wood- making are among the most fundamental in pathology, the facts distri- of blood-distribution come more visibly into the every-day mani- bution festations of disease. The speed and force with which the blood is driven round its whole circuit vary much ; as measured by the pulse at the wrist these conditions of the circulation have at all . -e blood-disks from a case of pcnii- C ious anaemia ; in the left lower corner is a group of normal red blood -disks for com- Parison. (After Laache.) times been held by practitioners to be of the first importance in diagnostics and prognostics. The local distribution of blood, -or the amount of it within and the rate of its passage through particular organs and parts, is a more recently investigated subject bound up with the doctrine of vaso-motor nerves. One of the most striking facts in this chapter of physiology is the varying amount of blood within the "splanchnic area" from time to time. In pathology the question of the varying distribution of blood comes largely into the doctrine of fever and of inflammation ; the further discus sion of it is reserved for a later part of the article. 1 7. ERRORS OF SECRETION. The pathology of secreting structures is concerned, not only with deviations from their normal activities as de scribed in physiological treatises, but also with an addi tional series of phenomena recalling the more elementary or embryonic kinds of cellular activity. Besides those great disorders of glandular structure and function which fall to be considered in the next section as errors of meta bolism, there is a large part of the sum -total of disease which is merely an affair of elementary cellular irregu larities in the mucous surfaces and glandular organs of the respiratory, digestive, and reproductive systems. In the foregoing illustrations of pathological processes it has often occurred to notice the obtrusion, as it were, of earlier phases of cellular activity into later life, or the revival of embryonic characteristics, both structural and functional. The illustrations already given have related chiefly to blood-making and bone-making ; we now come to a corre sponding class of illustrations from the epitheliated parts of the body. In the latter also there is a liability to revert to rudimentary forms of cell -life, wherein the epithelial cells reveal their inherent power to act as independent units, or their spontaneity and their self-governing properties. Thus, among the morbid conditions of the respiratory apparatus there are only a few, such as asphyxia, the Cheyne- and -Stokes breathing, and the like, which are directly in contact with the physiology of the respiratory mechanisms. On the other hand, pulmonary catarrhs and their structural after-effects (together with laryngeal and trachea! inflammations) enter largely into the pathology of the respiratory organs, although they are hardly devia tions from those respiratory functions that have the en grossing interest for physiology. There is the same class of elementary cellular deviations among the morbid states of the digestive organs, and, most of all, in the pathology of the genito-urinary system, of the uterus, bladder, and prostate, and of the breasts. The most universal error that epitheliated surfaces or organs are liable to is catarrh ; and closely related to their liability to catarrh is their liability to polypous and simple-glandular tumours, and, under special circumstances, to cancer. Catarrh in general. The term catarrh (KCLTOL, down ; ptw, flow) Catarrh was originally applied to a running from the nose ; the mucus was in gen- called " pituita," and in the Hippocratic doctrine of the humours it eral. was exalted to a place side by side with the blood and the bile. The vague importance assigned to this humour in the medical philosophy of the Greeks is further shown in the curious fiction which made it to issue from the hypophysis cercbri or "pituitary" body. The mucus of the nose may stand for the mucus of the air- passages generally, and it differs only in degree from that which is expectorated when there is considerable bronchial catarrh. It is now usual, and the usage is scientifically justified, to include all other mucous or muco - purulent or purulent discharges from epitheliated surfaces as the result of a "catarrhal" process. Those mucous surfaces that are most liable to catarrh are ordi narily kept moist by an exhalation or secretion ; in the mucous 1 See Virchow, Cellular- Pathologie, chaps, ix., x. ; Wilks, articles on leukaemia in Guy s Hosp. Reports, and in Wilks and Moxon, Path. Anat., 2d ed., London, 1875; M osier, Die Pathologie und Therapie der Leukamie, Berlin, 1872; Gowers, art. "Leucocytha?mia," in Rey nolds s System of Med. ; Malassez, in Arch, de Physiol., 1877 sq.; Pye-Smith, " Idiopathic Anoemia of Addison," in Guys Hasp. Reports, xxvi. ; Eichorst, Progressive perniziose Andmie, Leipsic, 1878; Laache, Die Andmie, Christiania, 18S3; Bizozzero, Rindrleisch, and others on the haematoblastic function. XVIII. 43