324 THE BLOOD. 



A very considerable decrease in the number of red corpuscles (300,000- 

 400,000 in 1 c.mm.) and diminution in the amount of haemoglobin ( T V) 

 occurs in pernicious anaemia (HAYEM, LAACHE, and others). On the 

 contrary, the individual red corpuscles are larger and richer in haemoglobin 

 than they ordinarily are, and the number stands in an inverse relation 

 to the amount of haemoglobin (HAYEM). Besides this the red corpus- 

 cles often, but not always, show in pernicious anaemia remarkable 

 and extraordinary irregularities of form and size, which QUINCKE l has 

 termed poikilocytosis. 



The number of leucocytes may, as stated above, be increased under 

 physiological conditions as well as after a meal rich in protein (physiological 

 leucocytosis) . Under pathological conditions a high leucocytosis may 

 occur, and this is especially found in leucaemia, which is characterized 

 by a very great abundance of leucocytes in the blood. The number of 

 leucocytes is markedly increased in this disease, and indeed, not only 

 absolutely, but also in relation to the number of red blood-corpuscles, 

 which are increased to a considerable extent in leucaemia. Leucaemic 

 blood has a lower specific gravity than the ordinary blood (1035-1040), 

 and a paler color, as if it were mixed with pus. The reaction is alkaline, 

 but after death it is frequently acid, probably due to a decomposition 

 of lecithin, which is often considerably increased in leucaemia. Volatile 

 fatty acids, lactic acid, giycero-phosphoric acid, large amounts of purine 

 bases, and so-called CHARCOT'S crystals (see Semen, Chapter XIII) have 

 also been found in leucaemic blood. The peptone (proteose) which is 

 found in the leucaemic blood after death, and which does not exist in 

 the fresh blood, is, according to ERBEN, 2 a digestive product which 

 is produced by a tryptic enzyme which originates from the leucocytes 

 as well as by traces of a peptic enzyme. A chemical analysis of leucaemic 

 blood has recentty been made by ERBEN. 3 



A great number of investigations have been made on the chemical 

 composition of blood in disease. But as we have only a few analyses 

 of the blood of healthy individuals, and as the possible variations under 

 physiological conditions are little known, it is difficult to draw any pos- 

 itive conclusions from the analyses of pathological blood. Unfortunately, 

 on account of the large number of contradictory deductions concerning 

 the composition of the blood of diseased human beings, it is impossible 



1 Laache, Die Anamie (Christiania, 1883), which also contains the literature; 

 Quincke, Deutsch. Arch. f. klin. Med., 20 and 25. A complete chemical analysis of 

 the blood has been made by Erben, Zeitschr. f . klin. Med., 40. 



2 Erben, Zeitschr. f . Heilkimde, 24, and Hofmeister's Beitrage, 5. See also Schumm, 

 ibid., 4 and 5. See also footnote 6, page 295. 



3 Zeitschr. f. klin. Med., 66 (1908). 



