THE RETICULOCYTE COUNT IN NORMAL AND IN ABNORMAL CONDITIONS

Abstract

Since the advent of vital staining, interest in the reticulocyte count as one index of regeneration of the blood has been much heightened. Among the earlier investigators to study reticulation was Ehrlich,¹ who by means of a dried blood film stained with a saturated solution of methylene blue (methylthionine chloride, U. S. P.), described nets in the red corpuscles in normal blood and in anemia. Twelve years later Askanazy² noted a reticulated substance in the erythrocytes of a rapidly progressive anemia. In 1901, Levaditi³ began the use of a brilliant cresyl blue as a vital stain, but did not mention reticulation. From 1907 to 1913 much work was done on reticulation. A brief summary of these studies will be found in Cunningham's article.⁴ In his own work Cunningham⁴ found that permanent preparations could be made by combining a vital stain with Wright's stain. He thought that the ease and simplicity