236 NORMAL AND PATHOLOGICAL BLOOD 





nor pernicious anaemia and for which no assignable cause can be designated. It 

 is a secondary anaemia without a cause. In it color index is about normal, there is 

 no change in the leukocytes and cases go on to recovery. 



Pernicious Anaemia. In pernicious anaemia we obtain a very 

 fluid, but normally colored drop of blood upon puncture. The yellow 

 marrow of the long bones is transformed into a soft, bright red lymphoid 

 tissue, smears from which show great numbers of megaloblasts. 



Areas of fatty degeneration are characteristic, especially the tiger-lily spots in 

 the heart muscle. Iron-containing pigment (hemosiderin) is found in the liver, 

 spleen, and kidneys. Areas of degeneration in the spinal cord may account for nerv- 



FIG. 56. Pernicious anaemia. M.m, Megaloblasts; n, normoblast; s, stippling 

 (punctate basophilia). (Cabot.) 



ous symptoms. The red cells frequently fall below 2,000,000 with patients going 

 about. Cases have been reported with counts under 200,000. The color index is 

 high. Megaloblasts are the most characteristic qualitative change in the red cells. 



Megaloblastic crises may at certain times show enormous numbers 

 of megaloblasts. Cases often present remissions in which no megalo- 

 blasts can be found. In such cases the presence of many macrocytes 

 should prevent an examiner's reporting against a pernicious anaemia 

 previously diagnosed. 



Poikilocytosis, polychromatophilia, and stippling are also features of the disease. 

 Normoblasts are far less frequent than megaloblasts and there is usually a moderate 

 lymphocytosis. Myelocytes may be present, but their precursors, the myeloblasts, 

 are probably more frequently met with. 



Cases of pernicious anaemia show remissions during which the patient is appar- 

 ently on the road to recovery. Such improvements are only temporary. The 

 remissions may last from two months to possibly three or four years. Especially 



