364 LEUKEMIA 



DIAGNOSIS 



The diagnosis of leukemia is in the majority of cases not difficult; indeed 

 it is very easy in well marked cases of the disease. We are always dealing 

 with leukemia when the proportion of white cells to red is 1 to 15 or less, 

 and the absolute count of leukocytes or lymphocytes (according to the ease) 

 is 30 to 50 times greater than normal, and when, besides the relative and 

 absolute increase in the number of white cells, an immaturity of the cells 

 is strikingly manifest. One finds in the blood besides mature leukocytes and 

 lymphocytes many large mononuclear cells and abundant myelocytes, large 

 lymphocytes and also immature forms of erythrocytes, i. e., nucleated red 

 blood-corpuscles in large or small amount's, and in most striking profusion 

 in leukocytic leukemia. In leukocytic leukemia we are struck, moreover, by 

 the absolute increase of eosinophiles and mast-cells. 



Having diagnosticated leukemia, we must now determine to which form 

 it belongs, whether to the lymphocytic or leukocytic type, which is not diffi- 

 cult if we remember the above mentioned points of distinction. 



If the immature forms of blood-corpuscles are absent from the circulating 

 blood, and if a " polymorphia " of the white corpuscles is lacking, we are not 

 dealing with a case of leukemia, at least not of leukocytic leukemia, but with 

 a leukocytosis in which myelocytes are never found (except in the very rare, 

 isolated eases in which there is an excessively hasty production of blood cells). 

 [Myelocytes are not at all infrequently found in leukocytosis, i. e., in peri- 

 tonitis, in diphtheria, in pneumonia and in malignant diseases. — Ed.] As 

 the blood pictures of leukocytosis and leukemia resemble each other in so far 

 as an increase in the number of leukocytes is concerned, we must now discuss 

 more thoroughly the manner in which leukocytosis originates, and the Hood 

 picture of leukocytosis. 



LEUKOCYTOSIS 



In some physiological processes, viz., during digestion, pregnancy, after 

 bodily exercise, etc., we find, upon examination of the blood, an increase of 

 the white cells. [That there is no leukocytosis of digestion or of pregnancy 

 seems to me demonstrated by the more careful researches of recent years. 

 There is a midday leukocytosis in most persons and this may coincide with 

 the after-dinner period. But after breakfast and after supper there are no 

 changes to speak of. 



The supposed leukocytosis of pregnancy is not observable, as a rule, until 

 a few days or hours before labor ; sometimes not until labor has begun. After 

 parturition there is usually a well marked leukocytosis lasting several days. 

 — Ed.J In this "physiological" leukocytosis the proportion of the various 

 forms of leukocytes to one another does not vary greatly from the normal, 

 whereas it is characteristic of pathological leukocytosis that, according to 

 the nature of the disease in the course of which a leukocytosis appears, marked 

 alterations are noted in the proportionate numbers of the various leukocyte 

 forms. According to whether the lymphocytes or the leukocytes are increased, 



