According to one view the melanin is produced in connection with the destruction of red globules in the liver, spleen, etc., and is thence carried into the blood. This is in keeping with the local formation of the pigment in melanosis. Arnstein however urges that in malarious cases the destruction of the red cells takes place in the blood, and that the hæmoglobin, absorbed into the leucocytes, is transformed into melanin, and finally deposited in the tissues by the migrating white corpuscle. Why the hæmoglobin set free in anæmia is not similarly transformed, does not appear. The pigmented organ may be quite black in the immediate vicinity of the blood vessels, and in its general aspect in chronic cases reddish brown, dark gray, or dark olive.
LEUKÆMIA. LEUCOCYTHÆMIA.
Definition. Nature. Result of other morbid processes. Leucocytes polynuclear. Lymphatic leukæmia. Spleno-myelogenous leukæmia. Leucocytes in each. Loss of amœboid movement. Charcot’s crystals. Hæmatoblasts. Cell increase in bone marrow. Myelocytes. Enlarged spleen and lymph glands. Hæmorrhages. Lymphoid growths. Susceptible genera. Causes obscure. Symptoms, pallor, listlessness, weakness, apnœa, sweating, thirst, emaciation, weak circulation, anæmic murmur, enlarged spleen, bleedings, diarrhœa, dropsy, excess of white globules, reduction of red globules, buffy coat, beaten fibrine is granular, china-white mucosæ, hurried breathing, stertor, deranged digestion, marasmus. Duration. Not inoculable. Treatment, not hopeful, as for anæmia, good hygiene, tonics, stimulants, antiseptics.
Definition. An excessive and persistent increase of the white blood globules, and associated with enlargement of the spleen, lymph glands or bone marrow.
Nature. This must be distinguished from the leucocytosis which occurs during digestion, or that which attends on tuberculosis, glanders, pneumonia, and other extensive inflammations and profuse suppuration. These forms are transient and the cells are of the polynuclear variety. The cells of leukæmia are various in character, but bear some relation to the particular organ which is the seat of hypertrophy or morbid process.
“In lymphatic leukæmia the increase in the number of leucocytes is due to the mononuclear lymphocytes, especially of the small form. As many as ninety-five per cent. of the colorless cells may be of this form. In Spleno-Myelogenous leukæmia the eosinophile cells may be especially increased in number, and there are also large leucocytes coming apparently from the marrow of the bones, and called myelocytes. These most nearly resemble the larger lymphocytes of normal blood, but they are usually larger. They have a single large nucleus which stains feebly and their bodies may show neutrophile granules. Larger and smaller nucleated red blood cells may be found in spleno-myelogenous leukæmia. The leucocytes are frequently in a condition of fatty degeneration, and there may be a decrease in the number of red blood cells.” (Delafield and Prudden). In splenic leucocythæmia blood plates may be absent and in lymphatic leucocythæmia they may be in excess.
Cafavy claims that many of the leucocytes have lost their active amœboid movements.
Bright white crystals in the form of elongated octahedra are found not only in the blood but in the diseased glands, spleen or marrow (Charcot’s crystals). Clusters of discoid hæmatoblasts (blood plates) are present in the blood in variable numbers (Schultze’s granule masses).
The bone marrow is marked by an accumulation of spheroidal cells, which tend to pass into a condition of fatty degeneration. Most of them are colorless, larger than the lymphocytes of normal blood and have one large often vesicular nucleus, staining less highly than the lymphocyte nuclei, and with neutrophile granules in the protoplasm (myelocytes). There are besides, nucleated red blood cells, spheroidal cells, containing red blood cells, and Charcot’s crystals. The marrow may be uniformly red, mottled gray and red, gray, grayish yellow, or puriform (Delafield and Prudden). This may affect one or many bones. The affected spleen is usually much enlarged, at first uniformly, later unevenly, firm or softened, and with thickened white capsule. The cut surface is smooth, brownish red, or yellow, with white lines (thickened trabeculæ) and indistinct Malpighian corpuscles. It contains glutin, glycocoll, hypoxanthin, zanthin, leucin, tyrosin, and lactic, acetic, or formic acids.
The affected lymph glands are somewhat enlarged, red or gray, exceptionally, softened or caseated and otherwise contain an excess of leucocytes.