3. =The absolute increase of the eosinophil cells.= In his first paper on leukæmia, Ehrlich stated that the absolute number of polynuclear eosinophils is always much increased in myelogenic leukæmia. This assertion of Ehrlich has been received under some protest; v. Limbeck in his text-book even speaks of an "alleged" increase of the eosinophil cells. The well-known work of Müller and Rieder has more particularly given rise to this opposition, and thrown doubt on the diagnostic importance of the eosinophil cells. These authors however base their contradiction on false premises.
For Ehrlich did not speak of a rise of the percentage of the eosinophil cells, but only of an increase in their absolute number. If in a case of leukæmia only the normal percentage number of eosinophils is found, it indicates, all the same, a great absolute increase; and Müller and Rieder would themselves have fully confirmed Ehrlich's statement, had they only calculated the absolute figures in a few of their cases. Selecting from the seven cases in this paper, those where it is possible from the given data to obtain the absolute number of the eosinophil cells, we get the following results:
Case 29 3.5% eos. 14,000 per mm.^{ 3} " 30 3.9% " 8,000 " " 31 3.4% " 11,000 "
The figure given by Zappert as a high normal value is 250. In these cases there is an average number of 11,000, that is 50 times as great. The observations then of Müller and Rieder themselves suffice fully to confirm Ehrlich's statement.
The absolute number of eosinophil cells depends naturally to a certain extent on the relative proportion of white to red corpuscles, and the greater the relative number of leucocytes, the greater should be the number of eosinophils. Zappert, for instance, found the following figures in his cases:
Proportion of white Absolute number to red corpuscles. of eosinophils.
1:24 3,000-4,560 1:18 3,300 1:15 7,000 1:13 8,700 1:11 6,000 1:7.6 8,300 1:7.0 7,600 1:7.0 29,000 1:5.0 14,000 1:3.8 34,000.
Apart from the approximate parallelism between the two rows of figures, this abstract shews that the minimal value--3,000 eosinophils with a proportion of white to red of 1:24--still amounts to 15 times the normal. The maximal figure found by Zappert of 30,000 is moreover by no means to be considered extreme. Cases of leukæmia are not infrequent in which we find 100,000 eosinophils per mm.^{ 3} and over.