a 



DIAGNOSTIC APPLICATIONS OP THE BLOOD-COUNT 24I 



a disease which does not occur in infancy. On the other hand, _ 

 high colour-index is not infrequent, and does not necessarily 

 point to pernicious ansemia, which is excessively rare. Lastly, 

 degenerative changes, such as poikilocytosis, granular degeneration, 

 and polychromasia, are very common, occur in comparatively 

 mild grades of anaemia, and have not the serious import they have 

 in the adult. 



Leucocytosis in Ancemia in Infants. —This, is very common, 20,000 

 to 60,000 being frequently met with; in most cases there is a 

 predominance of lymphocytes, and the presence of myelocytes is 

 quite common, rendering the diagnosis from leucocythaemia a 

 matter of some difficulty. As a general rule, the presence of a 

 high leucocytosis in infantile anaemia is a bad sign, and indicates 

 a worse prognosis than if it is absent. 



Secondary Anemia in Infancy [Syphilis, Rickets, Scurvy, Tubercle, 

 etc.). — There are no characteristic changes by which the different 

 causes of secondary aneemia can be recognized. The colour-index 

 is usually low (especially, iperhaps, in syphilis), normoblasts are 

 not uncommon, an occasional megaloblast may be seen, and there 

 is often leucocytosis, with increase of lymphocytes. 



Von Jaksch's Anemia {Anemia Infantum, Pseudo-leukemia). — It is 

 uncertain whether this is to be considered as a definite disease, as 

 an intermediate form between pernicious anaemia and leucocy- 

 thaemia, or as a form of secondary anaemia with somewhat 

 characteristic blood changes. I am rather inclined to the belief 

 that it does represent a definite blood disease, but that it is 

 frequently associated with, and perhaps due to, other diseases 

 such as syphilis, rickets, tubercle, or gastro-intestinal diseases. 

 The blood changes are — (i) An excessive grade of anaemia, usually 

 associated with a low colour-index ; in some cases, however, it 

 may be high, and I have seen it as high as i-8. (2) High 

 leucocytosis; often 50,000 or more, with extraordinary changes in 

 the leucocytes, so that they can hardly be classified on the usual 

 lines ; myelocytes are not uncommon. (3) Striking and profound 

 changes in the red corpuscles, the most important being the 

 presence of numerous normoblasts, many of which show dividing 

 nuclei (Plate VIII., Fig. 8) ; megaloblasts and atypical forms 

 occur, but are less numerous. The non-nucleated red corpuscles 

 show all forms of degeneration, poikilocytes, megalocytes, and 

 raicrocytes being present, whilst many are affected with granular 

 basophilia (Plate VIII., Fig. 2) or polychromatophilia (Plate VIII., 



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