Myelogenous Leukemia.
Synonyms.—Myeloid Leukemia; Splenic Myelogenous Leukemia; Splenic Leukemia; Leukocytic Leukemia.
Etiology.—This is a very rare disease, and but little is known as to its determining cause. It occurs more frequently in males than females, and between the ages of' twenty and fifty, though no age is exempt. It is found in all parts of the world, and among all races, though, according to Eichorst, the Jews are the most likely to suffer. Heredity seems to play an important part, while syphilis, malaria, unhygienic conditions, and injuries to the bone or spleen have been considered as predisposing, though they may be only coincident factors. Whether it be due to auto-infection or to bacteria is yet to be determined, though, whatever the cause, it affects directly the blood-making organs.
Pathology.—The Blood.—This is generally of a pale or creamy color, and contains Charcot-Leyden crystals. When leukocytosis is extreme, it resembles lymph or is milk-like or puriform, while at other times it may be of chocolate color.
It is less alkaline than normal blood, is of lower specific gravity, undergoes decomposition more rapidly, and does not coagulate so readily. The most characteristic factor of the disease is the great increase in the number of the leukocytes, there being 100,000 to 200,000 white corpuscles per cubic millimeter in a case of moderate severity, and a corresponding increase in the more severe cases, the relation of the white corpuscles to the red being as 1 to 2 or 1 to 1, and Robin states that the leukocytes may even double those of the red.
The Bone-Marrow.—Changes in the bone-marrow occur in both the long and spongy bones, the characteristic lesion being the "pyoid" transformation. The light appearance of the normal marrow is replaced by a yellowish or puriform color; this may be uniform, or scattered areas may be seen. In the early stage it may be firm in consistency, but as further changes take place, there is a tendency for it to liquify.
There is a marked increase in the colorless marrow-cells, and round hemoglobin free cells, with large pale nuclei and many fine granules possessing neutrophilic properties.
Spleen.—The spleen in the early stage is hyperemic, of a dark color, and very much enlarged, not infrequently extending downward to the spine of the ilium and forward to the median line. Infiltration and proliferation of lymphoid cells take place, the spleen becomes hard, and on section it presents a variegated appearance, due to small areas of fatty degeneration or necrosis, which are scattered throughout the organ, and which are due to pressure from the excessive infiltration; or there may be fibroid degeneration. In some cases there is hyperplastic thickening of the capsule with adhesions to the surrounding structures.
The Lymphatic Glands.—Though they are usually somewhat enlarged, they are secondary to myeloid leukemia, and may not be noticeable. It is simply an infiltration of the gland with leukocytes, and not a hypertrophy of lymphoid tissue. Similar infiltrations of leukocytes are found in most of the organs of the body.
The Liver.—In most of the cases examined the liver is found enlarged; but how much of this is due to hyperplasia of the liver tissue, and how much to a lymphomatous development, has not been determined.
Heart and Vessels.—Infiltrations are found in the heart and sometimes in the walls of the blood-vessels, but are due to secondary conditions.
Leukemic Retinal Changes.—With the ophthalmoscope, small infiltrations may be seen in the retina as small whitish spots, while the retinal veins are greatly enlarged, though the arteries remain normal.
Symptoms.—It is somewhat astonishing how well nourished many of these patients are, even after the alterations of the blood and enlargement of the spleen; many times the discovery of the disease is made when examining the patient for some intercurrent affection. In the advanced stage the patient complains of feeling weak and prostrated, bodily effort being difficult. The patient complains of pain in the side, there is hurried and oppressed breathing, more or less palpitation of the heart, loss of appetite and gastric disturbance, hemorrhage from the nose or gums; in fact, there may be hemorrhage into the various organs; pain and tenderness in the sternum and long bones, pallor of skin and mucous membranes, and marked anemia are the most characteristic symptoms. The temperature is quite erratic, in some cases being normal, subnormal in others, while a third class will show fever.
Diagnosis.—The diagnosis can only be made by the aid of the microscope, and, according to Lazarus, must show the following four conditions:
- "The granular mononuclear leukocytes (Ehrlich's myelocytes) must constitute a considerable number of all the white blood-cells. Their appearance in the blood is always somewhat abnormal; yet in nonleukemic cases, even when their percentage is moderately high, their absolute number is small, in fact far below the smallest numbers ever observed in myeloid leukemia.
- "The eosinophilia mononuclear and polynuclear cells must be considerably increased. Their percentage may not be greater than a high normal (three-quarters per cent), yet their actual number per cubic millimeter is incomparably greater than in the most marked cases of pure eosinophilia yet observed.
- "The mast cells must show a great absolute increase.
- "Nucleated red blood-corpuscles of especially normo-blastic type must be readily found. All of these characteristics must be present simultaneously."
Prognosis.—Medication has thus far proven of but little benefit, the patient dying sooner or later.
Treatment.—As already stated, medicines have had but little influence on the disease. Rest in bed, a nutritious and easily digested diet. Fowler's solution of arsenic, iron in some form, bone-marrow and oxygen inhalation, have been recommended. Polymnia deserves a trial.
The Eclectic Practice of Medicine, 1907, was written by Rolla L. Thomas, M. S., M. D.
