The practitioner's guide to clinical research : alphabetically arranged in sections.

Date:
[1914?]
Catalogue details

Licence: Public Domain Mark

Credit: The practitioner's guide to clinical research : alphabetically arranged in sections. Source: Wellcome Collection.

    16/208 (page 12)
    that the colour index is temporarily greater than 1. .n the late stages of any type of the disease the anemia becomes extreme, and all the changes in the red corpuscles characteristic of severe anemia may then be detected (pages 9 and 10). These are not of diagnostic value, but they are important in weighing the prognosis. Although the above are the only three blood diseases in which the diagnosis is actually made upon positive changes in the blood count, there are a great many other maladies in which the diagnosis remains in doubt until the blood has been exa- mined, and leuchemia or pernicious anemia have thereby been excluded. Thus, when one meets with a patient suffering from a very enlarged spleen, a complete blood count is required, more especially a total leucocyte count and a differential leuco- cyte count. If the result is negative, or indeterminate, leu- cheemia is excluded, and one of the various other causes of much enlarged spleen is indicated—cirrhosis of the liver, malaria, Kala-Azar, Hodgkin’s disease, splenomegalic polycythemia, in- fective endocarditis, or splenic anemia. If there is a pronounced tendency to cyanosis without dyspneea, and if without pathogno- monic changes in the white cells the red corpuscles are materially increased—perhaps to 7,000,000 per cubic millimeter, for in- stance—the diagnosis of splenomegalic polycythemia will be confirmed. The other conditions mentioned are not diagnosable by blood count alone. Malaria (see page 26) may be suspected if the patient has resided in the tropics, has had the charac- teristic pyrexial attacks, has chlorotic anzemia, leucopenia rather than leucocytosis, and exhibits a relative increase in the large lymphocytes in the differential leucocyte count, as in the follow- ing example:— Normal. Malaria. Polymorphonuclear cells ay se ons 65 one 58 Small lymphocytes ... at Sete 25 eid 21 Large lymphocytes _... wu wat ae 8 Baie 16 EKosinophile cells sins fie ces — 2 vite 4 Basophile cells ... des ve sit a _ — 0°5 Myelocytes ae se ve asi ves — ane 0°5 Additional evidence in favour of malaria is afforded by the occurrence of pigment granules of a golden brown or blackish colour both free in the blood stream and within some of the leucocytes. Similar pigment granules may also be found in the urine (page 111). The importance of these minor changes in the blood in malaria is greatest when the patient has had quinine before the blood had been examined, for the administra- tion of quinine rapidly depletes the peripheral blood of the characteristic malaria parasites (page 26) even when the doses