12-2 



KALLACIES AND PUZZLES IN BLOOD EXAMINATION 



Unrecognised 

 bodies from 

 the blood of a 

 donkey and a 

 gerbil 



Death and 

 degeneration 

 of leucocytes 



For instance, the spherical, homogeneous, blue-staining bodies, so often met with in 

 spleen smears in kala-azar, may be found in the peripheral blood, and to those not 

 accustomed to them prove a difficulty. They are, however, quite distinctive, especially 

 if one remembers that in all probability they are fragments of host cells (macrophages) 

 which, having been broken off, assume the spherical shape in the circulating blood. This, 

 however, is by no means proved, and what is one to make of the body shown iu Plate VII., 

 fig. 1, or that portrayed under fig. 6? 



The first is from the blood of a donkey which was possibly a recovered case of 

 piroplasmosis, the latter was from the blood of a gerbil which had been inoculated, 

 with negative results, from a goat, which in its turn had been inoculated with the 

 camel trypanosome of the Sudan. 



I confess I do not know what these bodies are, and I would be glad of suggestions. 

 The first is, possibly, not unlike the bodies into which mononuclear leucocytes may break 

 up (vide page US), and it is worth remembering that in severe and advanced cases of 

 piroplasmosis, whether bovine, equine or canine, the blood may show marked 

 degenerative changes and present curious pictures of cellular vagaries. From the same 

 donkey's blood comes Plate VII., fig. 9, and it is almost certainly merely a degenerated 

 leucocyte where the nucleus has undergone chromolysis. In the same category come, 

 no doubt, the strange cells, Plate VI., figs. 9 and 10, from the blood of a fowl which 

 was dying in what I have called the spirochajtal "after phase," or better, "granule 

 phase." There were myelocytes present in its blood and every evidence of great blood 

 destruction. 



The work of Ross on achromasia of the leucocytes and on the changes which occur 

 when they die, helps us to understand some of these appearances. After their death 

 polymorphonuclears and eosinophiles often appear mononucleated. This is possibly due 

 to liquefaction of the nucleus, its lobes running together. Liquefaction of the cytoplasm 

 is said to begin at the periphery of the cell, and progress towards the nucleus, while 

 in achromasia the granules of leucocytes turn red. It is well to keep in mind the 

 fact that in blood films we may possibly encounter white cells which had been 

 circulating as dead matter, and, therefore, exhibit changes which are never seen in 

 living cells. 



Apart from actual death, degeneration and vacuolisation may make leucocytes almost 

 unrecognisable, especially if there is much karyolysis of their nuclei. The clinical condition, 

 the history of the ease, other blood findings and the evidence of grave ansemia will 

 usually lead one to a diagnosis of such abnormal cells. Anyhow, they cannot well be 

 mistaken for anything else, and their outlines are too irregular and broken for them 

 to suggest protozoa. Plate VII., fig. 8, however, represents a parasite-like body, about 

 which I cannot give an opinion, though I expect it is derived from a white cell. It 

 was found in the blood of a gerbil which had been inoculated, without result, with 

 human spirocha9tal blood. The chromatin is well marked in it, and, as will be seen, it 

 is ring-like. 



Although not like these, this leads one to speak of oval or round rings which may 

 occur in the cytoplasm of lymphocytes. Certain forms, which Ross suggests may be 

 centrosomes, occur when blood is kept on a jelly and stained with an alkaline stain. 

 They are situated above or below the nucleus, not in it. Is it possible that such rings 

 may show, under certain conditions, in the peripheral blood ? I have seen in the 

 extra-nuclear portion of a camel's mononuclears, tiny chromatin-like and very perfect 

 rings, the significance of which is quite unknown to me. They were not numerous, and 



