THE BLOOD AND THE BLOOD-FORMING ORGANS. 385 



General Diseases Involving the Blood and Blood-Forming 



Organs. 1 



There is a group of diseases in which the essential lesion seems to be 

 an alteration in the composition of the blood, although in some members 

 of the group other lesions are also present. This group embraces Chlor- 

 osis, Secondary and Pernicious Anaemia, Leukaemia, and Pseudo- 

 leukamria. 



CHLOROSIS. 



Chlorosis is a disease of the blood, attended with a diminution in the 

 haemoglobin, and usually in the number of the red blood cells. 



Of the essential element in the incitement of this disease and of the 

 exact method of its origin we are ignorant. The_ondition has been at- 

 tribnted to congenital hypoplasia of the heart and blood -vesselsTto pro- 

 longed malnutrition, to intestinal intoxication, anfl Lo fimi'tloual dljJ- ' 

 turbanee of an unknown nature in the blood-producing organs. 



Tn the mildest grade of chlorosis the only change to be observed is a 

 diminution of haemoglobin. In severer forms may be added a diminution 

 in number and moderate variations in size and shape of the red cells. In 

 very severe and relapsing cases the haemoglobin may be excessively de- 

 creased ; the red cells may number less thairtvo million per' cubic milli- 

 '~m^rtTe7-aud~fhiraverage size of the cells be less than n</rihal. Tiie leucocytes 

 in number. There may be a slight relative increase of 



the lymphocytes ; megalocytes, microcytes, and poikilocytes may appear 

 (see Plate II., Fig. 2). 



The specific gravity of the_bloqd is diminished ; the alkalinity of the 

 blood and serum is, as a rule, diminished slightly, while the power of 

 coagulation remains normal. Even in cases of considerable severity the 

 degenerative changes in the viscera characterizing other forms of anaemia 

 have been found wanting, although degenerative changes in the red cells 

 may occur in accordance with the severity of the disease. The liver does 

 not contain an excess of iron, and the urine is free from pathological 

 urinary pigments. 



The regeneration of the blood in chlorosis under rest and treatment 

 with iron may usually be rather promptly effected by increased activity 

 of the red marrow which is probably hyperplastic. This regenerative 

 process may be indicated in the blood by the periodical appearance of 

 considerable numbers of normoblasts. The appearance of these nucleated 

 red cells may be accompanied by a moderate increase of leucocytes, both 

 mouonuclear and polyuuclear. Myelocytes also may rarely be seen. 



1 For a full discussion of the subjects treated in this chapter the reader is referred 

 to Von Noorden. "Bleichsucht," Nothnagel's " Spec. Path. u. Therap."; and to Ehrlieh 

 and Lazarus, "Die Auaemie," Nothnagel's "Spec. Path. u. Therap." 

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