Hematology

“ Oligocythemia occurs in all but the mildest symptomatic anemias. The blood count varies from near the normal in moderate cases down to 1,500,000 in very severe cases. There is always a decrease of red cells in chlorosis, but it is often slight, and is relatively less than the decrease of hemoglobin. Leukemia gives a decided oligocythemia, the average count being about 3,000,000. The greatest loss of red cells occurs in pernicious anemia, where counts below 1,000,000 are not uncommon. ”

“ Myelocytes are rare.
The red corpuscles show the changes usual in severe secondary anemia. Erythroblasts are seldom abundant. Blood-plaques are decreased.
3. Pseudoleukemia (Hodgkin's disease) resembles lymphatic leukemia in that there is marked and progressive enlargement of the lymph-nodes. There is, however, no distinctive blood-picture. The changes in hemoglobin and red cells resemble those of a moderate symptomatic anemia, with rather low color-index. The leukocytes are commonly normal in number and relative proportions. ”

“ These really negative observations shew that the mitoses play a completely negligeable part in the increase of the cells in the blood itself. For the diagnosis of leukæmia they are valueless.
6. Nucleated red corpuscles form a constant constituent of leukæmic blood. In different cases their number is very varying; in one case they occur extremely sparingly, in another every field contains very many. The normoblastic type is found most frequently, but side by side with it, megaloblasts and forms transitional between the two are occasionally found. ”

“ We owe to them the exact distinction between the several kinds of white blood corpuscles, a rational definition of leukæmia, polynuclear leucocytosis, and the knowledge [Pg 30] of the appearances of degeneration and regeneration of the red blood corpuscles, and of their degeneration in hæmoglobinæmic conditions. The same process, then, has gone on in the microscopy of the blood that we see in other branches of normal and pathological histology: by advances in method, advances in knowledge full of importance result. ”

“ One of the most important points indicated in the following pages is that the cellular elements of the blood must be studied as a whole and not as isolated factors, as "it has always been shown that the character of a leukæmic condition is only settled by a concurrence of a large number of single symptoms of which each one is indispensable for the diagnosis, and which taken together are absolutely conclusive." ”

“ Lymphocytes are formed in the lymphoid tissues, including that of the bone-marrow. They constitute, normally, 20 to 30 per cent. of all leukocytes, or about 1000 to 3000 per c.mm. of blood. They are more abundant in the blood of children.
The percentage of lymphocytes is usually moderately increased in those conditions which give leukopenia, especially typhoid fever, chlorosis, pernicious anemia, and many debilitated conditions. A marked increase, accompanied by an increase in the total leukocyte count, is seen in pertussis and lymphatic leukemia. ”

“ By his eminent labours in cellular pathology, Virchow, and Metchnikoff later, gave the last blow to the mere humoral pathology which, after an almost unchallenged prevalence for some two thousand years, now finds a resting-place only in our nurseries. Now the cellular pathology of the blood, investigated by the aid of modern staining methods, is as important as that of the solid organs; no clinical investigator—indeed, apart from research, no practitioner at this day—can dispense with examination of the blood for purposes of diagnosis ”

“ It is a rare condition, and must be distinguished from hematuria, or blood in the urine, which is common. In both conditions chemic tests will show hemoglobin, but in the latter the microscope will reveal the presence of red corpuscles. Urines which contain notable amounts of hemoglobin have a reddish or brown color, and may deposit a sediment of brown, granular pigment.
Hemoglobinuria occurs when there is such extensive destruction of red blood-cells within the body that the liver cannot transform all the hemoglobin set free into bile-pigment. ”

“ I believe that in time we shall be able to refine this test to tell the exact individual, too.
"What is this principle? It is that the hemoglobin or red colouring-matter of the blood forms crystals. That has long been known, but working on this fact Dr. Reichert and Professor Brown of the University of Pennsylvania have made some wonderful discoveries.
"We could distinguish human from animal blood before, it is true. But the discovery of these two scientists takes us much further. ”

“ This simple method holds good for all counts of 1,000,000 or more. Thus, a count of 2,500,000 is 50 per cent. of the normal. If, then, the hemoglobin has been estimated at 40 per cent., divide 40 (the percentage of hemoglobin) by 50 (the percentage of corpuscles) . This gives 4/5, or 0.8, as the color index.
IV. ENUMERATION OF LEUKOCYTES
The normal number of leukocytes varies from 5000 to 10,000 per cubic millimeter of blood. The number is larger in robust individuals than in poorly nourished ones, and if disease be excluded, may be taken as an index of the individual's nutrition. ”

“ The lesson is, that boys who are bleeders may marry, because they will most likely not transmit the disease; but girls who come from a hemophilic family, irrespective of whether they themselves are hemophilics or not, must not marry, because most likely they will transmit the disease.
Anemia
Anemia is a poor condition of the blood. The blood may contain an insufficient number of red blood cells or an insufficient percentage of the coloring matter of the blood, that is, hemoglobin. A special kind of anemia affecting young girls is called chlorosis. ”

“ In a case of carcinoma of the bone-marrow, described by Epstein, with an anæmic constitution of the blood (nearly always present it may be mentioned in leukæmia) , there was found a marked increase of the white blood corpuscles, numerous neutrophil myelocytes and nucleated red corpuscles. Anyone holding, as Müller and Rieder do, that the number of eosinophil cells need not be considered in the diagnosis, must in this case have diagnosed myelogenic leukæmia. ”

“ They are most abundant in myelogenous leukemia. While always present in pernicious anemia, they are often difficult to find. Megaloblasts are found in pernicious anemia, and with extreme rarity in any other condition. They almost invariably [p. 178] exceed the normoblasts in number, which is one of the distinctive features of the disease. Microblasts have much the same significance as normoblasts, but are less common.
2. The Leukocytes.—An estimation of the number or percentage of each variety of leukocyte in the blood is called a differential count. ”

“ The glands act as filters, arresting not only inert substances, such as blood pigment circulating in the lymph, but also living elements, such as cancer cells or bacteria. As it passes through a gland the lymph is brought into intimate contact with the leucocytes, and in bacterial infections there is always a struggle between the organisms and the leucocytes, so that the glands may be looked upon as an important line of defence, retarding or preventing the passage of bacteria and their products into the general circulation. ”

“ Normoblasts are very numerous and megaloblasts appear later. There is both polychromatophilia and poikilocytosis. The color index is that of pernicious anaemia, above 1. The leucocytes are increased to about 20,000 with 75% of neutrophiles, among which are many immature forms or metamyelocytes. The pathological process shows its greatest activity in the bone marrow.
Malta Fever.—In this disease blood cultures offer the surest and most practical way of making the diagnosis. The blood should be taken from a vein at the time of the height of the fever rise. ”

“ These granules are identical with the corresponding granules in the leukocytes just described. The occurrence of two kinds of granules in the same cell is rare.
Myelocytes are the bone-marrow cells from which the corresponding granular leukocytes are developed. Their presence in the blood in considerable numbers is diagnostic of myelogenous leukemia. The neutrophilic form is the less significant. A few of these may be present in very marked leukocytosis or any severe blood condition, as pernicious anemia. ”

“ It was with mounting admiration that he followed her new project in examining blood samples. As they came up from the clinic, she sorted the specimen tubes at once, putting a tiny snip of yellow Scotch tape under the label of each sample that belonged to a patient with the new undiagnosed disorder.
Then, after the requested hemoglobin, blood sugar and other standard tests had been run, she retrieved the samples from the technicians, grouped them in a special rack and devoted every spare minute to further examination. ”

“ For the comprehension of the histology of the blood as a whole, it is of great importance to obtain an exact knowledge how and to what extent the three organs, which are undoubtedly very closely connected with the blood, lymphatic glands, bone-marrow, and spleen, contribute to its formation. ”

“ The hematocrit is not to be recommended for accuracy, since in anemia, where blood counts are most important, the red cells vary greatly in size and probably also in elasticity. [p. 151] The hematocrit is, however, useful in determining the relative volume of corpuscles and plasma, and seems to be gaining in favor.
The Thoma-Zeiss instrument consists of two pipets for diluting the blood and a counting chamber (Fig. 69) . The counting chamber is a glass slide with a square platform in the middle. ”

“ If the demand be for the red cells owing to loss from hemorrhage or any of the anaemias, the fatty marrow is rapidly replaced by cellular elements; this is mainly an active proliferation of the nucleated red cells, and gives rise to the erythroblastic type of marrow. If the white cells be required, as in local suppurating abscess, general septicaemia, acute pneumonia, &c., there is an active proliferation of the myelocytes to form the polymorpho-nuclear leukocytes, so that we have in this condition a leucoblastic transformation of the fatty marrow. ”

“ We merely take a sterilized swab of cotton on the end of a wire, rub it gently over the surface of the throat and tonsils, restore it to its glass tube, smearing it over the surface of some solidified blood-serum placed at the bottom of the tube, close the tube and send it to the nearest laboratory. The culture is put into an incubator at body heat, the germs sown upon the surface of the [Pg 234] blood-serum grow and multiply, and in twelve hours a positive diagnosis can be made by examining this growth with a microscope. ”

“ The clinical experience, that in acute losses of blood in man, these staining anomalies, can be observed in numerous cells, within so short a time as the first 24 hours. Whilst in our observations, which are very numerous upon this point, embracing several hundred cases, and carried out with particular care, no nucleated red blood corpuscles in this space of time can be found in man [8] .
4. The polychromatophil degeneration can frequently be observed in nucleated red blood corpuscles, particularly in the megaloblasts. ”

“ The actual number of each variety in a cubic millimeter of blood is easily calculated from these percentages and the total leukocyte count. An increase in actual number is an absolute increase; an increase in percentage only, a relative increase. It is evident that an absolute increase of any variety may be accompanied by a relative decrease.
A record is generally kept of the number of nucleated red cells seen during a differential count of leukocytes. ”

“ A hematoma acts as an irritant, inflammation ensues around it and it is encapsuled by embryonic tissue, which, by organizing into fibrous tissue, forms a blood cyst and gradually absorbs the fluid blood, the cysts contents becoming thicker and thicker. A fibrous scar may remain, and a blood clot, with very much indurated surrounding tissue, giving a hard edge, is noticed after bruises of the periosteum. If serum is not absorbed, hematoidin forms and the fluid becomes clear. ”

“ In leukæmia, besides the myelocytes, the polynuclear leucocytes are also enormously increased, and their active emigration is beyond doubt. And the view, that the mononuclear cells are washed into the blood, excludes that of a single mode of origin of the leukæmic blood condition; and commits us to a highly artificial explanation of its production. ”

“ Leucocytes are constantly being worn out by physiological use and as constantly yielding up their complement to the blood as they go to pieces. It would appear, then, that the very essential complement which exists in the circulating blood and passes from the blood into the lymph and serous cavities, will be more or less determined in quantity by the number of blood leucocytes and the conditions to which they are exposed, and as they are brought to slower or faster degeneration ”

“ The polymorpho-nuclear leukocytes are seen in great numbers in the blood vessels.
In health these cells, belonging to our first army of defenders, are found continually circulating in the blood stream in fairly large numbers; they are ever ready to rush to the point of attack, where they at once leave the blood stream by passing through the vessel walls—emigration—into the tissues of the danger zone. There they show marked phagocytosis, attacking and taking up into their interior and destroying the micro-organisms in large numbers. ”