111 Boston Med. and Surg. Journal, 1871.
112 Loc. cit.
113 Archives of Scientific and Practical Medicine, New York, 1873.
114 Med. and Surg. Reporter, 1883, 48.
115 Ibid., 1874.
Blood-vascular System.—In a well-marked case the blood-drop squeezed from the finger-tip is more or less turbid, of a reddish-brown or in extreme cases chocolate-brown color.
The blood should be examined in a thin layer, and for this purpose it is better to take a small than a large drop. A rough estimation of the proportion of white corpuscles can be much better obtained when a uniform thin layer is beneath the top cover. The red corpuscles, as a rule, present no striking changes, no special alterations in size or shape. Microcytes are occasionally seen, and now and then larger forms, but the extreme variations of pernicious anæmia are rarely met with. They are reduced in number, but not often to a great extent. A reduction below 2,000,000 to the cubic millimeter has been exceptional in cases which I have examined. In only one did the number sink to 1,500,000 per c.m. Laache116 has noted a case in which, with enlargement of the spleen and a ratio of white to red of 1:17, the number of red corpuscles was little if at all reduced.
116 Die Anämie, Christiania, 1883.
The colorless corpuscles are enormously increased. Instead of eight to ten millions per c.m., as in normal blood, they may reach 500,000 per c.m. or even 700,000 per c.m. The ratio of white to red cells may be 1:20, 1:10, 1:4, or they may even equal or exceed the red. Without a proper apparatus (Gowers, Malassez, or Zeiss) an accurate estimate is impossible, and it is chiefly upon the rough-and-ready method that the statements are made of the white exceeding the red in numbers. It is very seldom indeed that this is the case, and even in extreme leukæmia the ratio does not often reach 1:3 or 1:2. In none of my observations did the ratio rise to 1:1; the highest was 1:2. Cases are on record in which the white have exceeded the red: Sörensen's,117 where the red per c.m. were 470,000 and the white 680,000, and in an interesting observation of Fleischer and Penzoldt,118 as a mean of 57 accurate counts, the ratio of white to red was 115:100. The corpuscles have the natural grayish-white appearance of leucocytes, but differ in certain points from normal white blood-cells. The variations in size are greater: in normal blood only a few may be seen less than 1/2800 or 1/3000 of an inch, but in leukæmia on a single slide there may be colorless cells with the extreme measurements of 1/2000 and 1/3500. In ordinary cases we meet with—(1) cells of the average size, about 1/2800 of an inch in diameter, like normal corpuscles, with two or three nuclei and fine granular protoplasm; (2) smaller forms, 1/3000 of an inch and under, with single nuclei, resembling rather lymph-cells, and they were believed by Virchow to indicate special involvement of the lymph-glands, but they are present in all forms, though possibly more prevalent in the lymphatic variety; (3) large forms, 1/2000 to 1/1500 of an inch, with bold nuclei and bearing a close resemblance to the marrow-cells. They are not always present, and are believed to originate in the marrow.
117 Virchow-Hirsch's Jahresber., 1874.