LEUKEMIA 



By W. von LEUBE, Wurzburg 



Since the discovery of leukemia by Virchow in 1845, we designate by this 

 term a disease characterized by an increase in the number of white cells in the 

 hlood as the result of the morbid activity of the blood-forming organs, and in 

 which the blood alteration forms the essential feature of the progressive and 

 pernicious course of the disease. [The blood changes dominate the clinical 

 picture, and are manifest in many organs post mortem, but it is the belief of 

 most authorities that the heightened activity of glands and marrow to which 

 they are due is itself a result of some toxic (chemotactic) stimulus. — Ed.J 



This definition is sufficient clearly to differentiate " leukocytosis " from 

 leukemia. In leukocytosis we are, in fact, also dealing with an increase of 

 the leukocytes in the circulating blood ; but this is a transitory symptom in the 

 course of manifold diseases. At the same, leukocytosis is not, like leukemia, 

 a morbid condition of a progressive and pernicious nature; on the contrary 

 it is in a measure the expression of the self-protective power of the body 

 against the disease present. 



COMPOSITION OF THE BLOOD 



Without a thorough knowledge of the composition of the blood and of 

 the genesis of its different morphologic elements, an insight into the nature 

 of leukemia is impossible. We shall, therefore, describe briefly the normal 

 condition of the blood and of its cellular elements before we discuss leukemia 

 in detail.^ 



The three formed elements of the blood are, as is generally known, the 

 red blood cells, the white blood cells and the blood-plaques. These last have 

 thus far little, or no, importance in pathology. 



The red blood cells, "erythrocytes," are flat, circular, biconcave discs, 

 averaging 7.5 micromillimeters in diameter. Normally they do not contain 

 a nucleus, but consist of a protoplasmic stroma the gaps of which are filled with 

 hemoglobin. The formation of the red blood-corpuscles occurs in embryonic 

 as well as in post-fetal life from nucleus-containing, colored blood cells, the 



1 This article relating to the diagnosis and pathogenesis of leukemia is based, in the 

 main, upon the complete and recently revised chapter on Leukemia in the sixth edition 

 of my "Special Diagnosis of Internal Diseases" (English edition, Leube-Salinger, D. 

 Appleton & Co., 1904.) 

 844 



