LEIICOCYTHEMIA (leukhmia), although a rare disease in childhood, is oc casionally seen in the young subject, and therefore may be shortly de scribed. The disease is characterised by great excess of the leucocytes of the blood, enlargement of the spleen, sometimes of the lymphatic glands, and a morbid state of the bone medulla. Two cases have come under my notice, both in children under three years old. In each of these the malady assumed a febrile form, and was accompanied by enlargement of the spleen without any apparent affection of the lymphatic glands. In lymphadenoma, which is described elsewhere, an increase in the number of the white cor puscles is exceptional. Sometimes, however, in that disease excessive over growth of lymphatic elements is combined with multiplication of the colour less blood-cells. These cases present a great resemblance to the lymphatic form of leucocythemia, and, indeed, anatomically appear to be almost in distinguishable from it. In the present chapter the splenic form of leucocythemia will alone be described.
Causation.—The etiology of leucocythemia is not clear. Out of 150 cases analysed by Dr. Gowers in one-fourth there was a history either of ague or of habitation in an ague district. Of my own two cases, one had lived at Malta ; the other was a resident of London, but had lived in a street in which the roadway had been broken up for repairing and relay ing drains ; and for two or three months the upturned soil, saturated with coal-gas and other unhealthy effluvia had remained heaped up by the side of the foot-pavement. The disease appeared shortly before the close of these operations, and I cannot but think that the illness took its rise in the offensive emanations to which the child had been constantly exposed.
Morbid Anatomy.—The spleen is enlarged and may reach a great size. This increase is due to an overgrowth of the spleuic pulp, the leucocytes and the fibrous stroma being equally increased. The organ, although en larged, retains its normal proportions, so that its shape is not changed. Its density is increased and its colour is paler than natural. On the surface it is smooth unless local peritonitis have occurred, in which case particles of lymph may adhere to the capsule. From this cause it may contract ad
hesions to parts in its neighbourhood. Its section is smooth and of a brownish-yellow colour mottled with paler streaks from thickened tra beculm, and but little blood escapes from it on pressure. The Malpighian bodies are not very prominent, and may be seen under the microscope to be the seat of fatty or lardaceous degeneration.
The liver is often enlarged from congestion, and may be fatty. The kidneys, too, are often the seat of fatty degeneration: ex travasations are common, and may be seen in the skin, the heart, the lungs, the brain, and the retina, and fluid effusions may be found in the serous cavities.
In some cases the lymphatic glands undergo slight enlargement, but the increase in size is rarely universal as it is in lymphadenoma. On examination they appear to be normal in structure without any hyperpla sia of the reticalunl, and suppuration or caseation rarely occurs. As in lymphadenoma, adenoid growths may be also found in the tonsils, the follicles of the tongue, the glands of the stomach and intestines, and in other situations. The capillaries in various parts are distended with col lections of leucocytes. The marrow of the bones is more fluid than natural, is grayish in colour, and shows an accumulation of white and red corpus cles. The blood itself is much altered. It is pale in colour, coagulates loosely, and shows an enormous excess of white corpuscles, together with a diminution in the number of the coloured cells. Consequently the rel ative proportions, instead of being one white to four hundred and fifty red, as in health, may fall to one to twenty, one to ten, one to five, or even to an * actual equality of number. The white cells may also present peculiar char acters. They are sometimes seen of two quite different forms ; the one double the size of the other and full of small fat granules. According to Mosier, this larger form is evidence of morbid change in the bone medulla. After death thick creamy-looking clots may be found in the cavities of the heart, the terminal branches of the pulmonary artery, and the systemic vessels.