Eosinophil

“ Hence the eosinophil cells only emigrate to those parts where a specific stimulating substance is present. From this point of view experiments and clinical observations known up to the present on eosinophilia may be readily explained. Neusser's experiment for instance may be explained in the following way. In the pemphigus bullæ a substance is present that chemiotactically attracts the eosinophils. Hence the cells normally contained in the blood emigrate into them, and produce the picture of an eosinophilous suppuration. ”

“ For we know from our observations on leucocytosis in infectious diseases that the bacterial stimulating substances act on the eosinophil cells rather in a negative than in a positive sense. And if ordinary sputum is not rich in eosinophils in spite of a marked eosinophilia of the blood, this only corresponds to our experience in general. ”

“ The breaking up of ordinary pus cells or lymphocytes does not appear to give rise to any such substances; but there is much evidence that the decomposition products of epithelial and epithelioid cells act chemiotactically. Thus we can explain the frequent occurrence of eosinophilia in all kinds of skin-diseases. Again, in all atrophic conditions of the gastric, intestinal and bronchial mucous membrane there occurs a local accumulation of eosinophil cells; further, this kind of cell is increased in the neighbourhood of carcinoma. ”

“ The mononuclear eosinophil cells. Before the introduction of the staining method, Mosler had described large, coarsely granulated cells, "marrow cells," as characteristic for myelogenic leukæmia. These are to be regarded as for the most part identical with the mononuclear eosinophil cells, noticed by Müller and Rieder as peculiar, and aptly described by them as the eosinophil analogues of the preceding group. They appear as large elements with oval, feebly staining nucleus. ”

“ The eosinophil cells. These are characterised by a coarse, round granulation, staining deeply with acid dyes, and similar in other respects to the polynuclear neutrophils. With faint staining, a thin peripheral layer of the eosinophil granule is seen more deeply stained than the interior. The nucleus as a rule is not so deeply stained as in the polynuclear neutrophil, but otherwise in its general shape is completely similar. Both forms have in common a considerable contractility, which renders possible their emigration from the vessels, and their appearance in exudations and in pus. ”

“ Here it exercises a strong chemiotactic influence on the physiological storage depôt of the eosinophils, the bone-marrow; leading to an increase of the eosinophils of the blood to a greater or less degree. The bone-marrow, according to general biological laws, is by the increased emigration now further stimulated to a fresh production, and during a protracted illness can hence keep up the eosinophilia.
In this way other clinical observations may be explained. Gollasch has found that the sputum of asthmatic patients contains, in addition to Charcot-Leyden's crystals, eosinophil cells only. ”

“ Thus it is evident from a number of various facts, that the eosinophil cells found in the tissues are not formed there, but have immigrated from the blood-stream. It naturally often happens that this appearance is not preserved equally distinctly in all cases. For, as has been seen in the ordinary polynuclear leucocytes, the immigrated polynuclear eosinophils may similarly change to mononuclear cells; they may perhaps settle down, and approximate to the character of fixed connective tissue cells. ”

“ The clearest proof that the neutrophil, eosinophil, and mast cells are entirely separated from one another by the fundamental diversity of their protoplasm, of which the granulation is but a specially striking expression, is afforded by the study of the various forms of leucocytosis. As will be shewn in detail in the following chapter, neutrophil and eosinophil leucocytes behave quite differently in their susceptibility to chemiotactic stimulation. Substances strongly positively or negatively chemiotactic for one cell group are as a rule indifferent for the other ”

“ Mononuclear eosinophil cells ("eosinophil myelocytes") . H. F. Müller was the first to point out their importance. They constitute the eosinophil analogue of the previous group, and are much larger than the polynuclear eosinophils; medium and small sized examples are often found in leukæmia. Eosinophil myelocytes are almost constantly present in myelogenous leukæmia and in anæmia pseudolymphatica infantum. Apart from these two diseases they are very rarely found; Mendel saw them for example in a case of myxœdema, Türk quite exceptionally in some infectious diseases. ”

“ The typical eosinophil leucocytes, which fully correspond to those found in man, and amount to about 10% of the number of the white. [Pg 86]
3. The "nigrosinophil cells," as they are called by Kurloff. In their general appearance, in the size of the cell and the granulation, they completely correspond to the eosinophil cell. The only distinction between them consists in a chemical difference in the granulation. These cells stain in the colour of nigrosin in the aurantia-eosin-nigrosin mixture, whilst the eosinophil cells become red. ”

“ An experiment frequently quoted as explanatory is that of Müller and Rieder's; these authors do not derive the eosinophil cells of the blood from the bone-marrow, but assume, as very probable, that the finely granular cells grow into eosinophils within the blood-stream. This developmental process seems very improbable for many reasons. Since the polynuclear cells circulating in the blood are all under the same conditions of nutrition, it is à priori inconceivable why only a relatively small portion of them should undergo the transformation in question. ”

“ One expression of these distant actions is, as Leichtenstern insists, the eosinophilia of the blood. We do not think we should assume on the evidence before us, that the substance which attracts the eosinophil cells is identical with the cause of the anæmia. Many observations, the absence, for example, of eosinophilia in Bothriocephalus anæmia (Schauman) , render probable the existence of two different functions. In any case the substance causing the eosinophilia is more widely distributed than that to which the anæmic condition is due.
Leukæmia. ("Mixed leucocytosis.") ”

“ For if in the places in question substances are present which act chemiotactically on the eosinophil leucocytes, in the course of time marked accumulation must occur, without an increase of their number in the blood. One might as well conclude from Neumann's experiment in lymphatic leukæmia, for example, where the artificial suppuration consisted only of polynuclear neutrophil cells, that the polynuclear cells were formed in the tissue, since in the blood they were present in very small percentage. ”

“ Ordinary pus-cells are easily recognized in sputum stained by any of the methods already given. For eosinophilic cells, some method which includes eosin must be used. A simple method is to stain the dried and fixed film two or three minutes with saturated solution of eosin, and then one-half to one minute with Löffler's methylene-blue; nuclei and bacteria will be blue, eosinophilic granules bright red.
(2) Epithelial cells may come from any part of the [p. 42] respiratory tract. A few are always present. ”

“ The standard of comparison for a leukæmic patient suffering from severe sepsis is not the blood of a healthy person with normal numerical proportions, but that of a patient similarly attacked by a severe sepsis. Now we know that in sepsis the number of eosinophil cells is enormously diminished, so that Zappert, in five cases of this nature, was unable to recognise any eosinophils in the blood. In contrast to this stands a case of myelogenic leukæmia described by Rieder and Müller, complicated by a severe and lethally ending suppurative process. ”

“ This would be at the site of a bite in an immune individual. A point of special interest for further investigation, would be the study of such a lesion.
Second, it is conceivable that the injected saliva of the fly does not contain an agent toxic as such. It is possible, that like many foreign proteins, it only becomes toxic when broken down. The completeness and rapidity of the breaking down depends on the number of eosinophiles present. In such a case immunity should again be marked by intense eosinophilia. ”

“ X-ray treatment tends to destroy leucocytes in the exposed region, especially polymorphonuclears. The small lymphocytes are least affected.
Eosinophilia
Where the eosinophiles are increased to 5%, we have a moderate eosinophilia. In some cases of infection with intestinal parasites, especially hookworms, but also from other parasites, as round and whip-worms, we may have an eosinophilia of 30 to 50%. In Guam, among the natives, it is difficult to find an eosinophile count under 15%. The eosinophilia tends to disappear when the anaemia becomes very severe. ”

“ The rise may be very considerable. In one case of [Pg 153] Zappert's the number of the oxyphils increased to 26.9%; in another of his cases the highest absolute figure formed after tuberculin injections was 3220 per mm.3 In a case of Grawitz' the eosinophilia was quite extraordinary. The most marked changes in the blood occurred some three weeks after cessation of the tuberculin injections, of which eight altogether (from 5 mg. to 38 mg.) were given. Investigation shewed 4,000,000 red blood corpuscles per mm.3, 45,000 white. Amongst the latter there were ten eosinophils to one non-eosinophil. ”

“ Trichiniasis is generally accompanied by a marked eosinophilia. The diagnosis is made by teasing out upon a slide a bit of muscle, obtained preferably from the outer head of the gastrocnemius, the insertion of the deltoid, or the lower portion of the biceps. The coiled embryos can easily be seen with a two-thirds objective (Fig. 108) .
(5) Uncinaria.—The two varieties of this worm, Uncinaria duodenalis and Uncinaria Americana, are among the more harmful of the animal parasites. They inhabit the small intestine, usually in great numbers, and commonly produce a severe and often fatal anemia. ”

“ The occurrence of the broad tapeworm in man is often associated with anaemia of a most severe type. The coloured constituents of the blood are most affected. New elements appear in addition to degenerative changes in the normal red corpuscles. Large nucleated red blood-cells make their appearance. The white blood-cells, or leukocytes, undergo other changes. In hydatid disease there is, as a rule, a marked increase in the number of those white corpuscles which possess a specially staining affinity with the dye eosin, and are therefore known as eosinophile cells. ”

“ Charcot-Leyden crystals are often present in hookworm stools.
Prognosis
The disease is more serious in children than in adults, on account of its interfering with physical and mental development. The dark races do not seem to suffer as much as the white ones. Treatment is usually most successful, but in those who are debilitated by other diseases or, in those in whom the disease has assumed a pernicious anaemia tendency, the outlook is not good.
The presence of eosinophilia is of good prognostic significance as the absence of eosinophiles indicates an exhaustion of the haemopoietic system. ”

“ In myelogenous leukemia there is almost invariably an absolute increase of eosinophiles, although, owing to the great increase of other leukocytes, the percentage is usually diminished. Dwarf and giant forms are often numerous. ”