Fallacies and Puzzles in Blood Examination 



Being au account of the more common deceptive appearances met with in such work, 



especially in tropical countries 



BY 



The Dikeotou 



It has occurred to me that, for those at least who are novices in the art of blood 

 examination, and more especially for such resident in tropical countries, a short paper 

 on some of the more common sources of error encountered in this work may be useful. 

 It is true that some of them are mentioned in the text-books, more especially in volumes 

 devoted to malaria, but, even in these, I find there are many omissions, and one has to 

 search through papers on various subjects before one gets an idea of all the pitfalls 

 into which the hasmatologist may be plunged. 



Moreover, it would seem that there is an urgent need, in English at least, for some 

 such article. From time to time one finds descriptions of so-called blood parasites. Objects 

 either in man or animals, which it does not require a Solon to diagnose as being in ^™"gy'-* ^ 



' ^ o o blood parasites 



reality one or other of the conditions we propose to describe, and not haematozoa at all. 



For example, to take two recent instances, I would cite the papers on blackwater 

 fever by Dr. Foran of Nigeria, and Dr. Breeze of Tangiers, respectively. 



Dr. Foran describes what he believes to be piroplasmata in stained films and what 

 he regards as free forms in fresh blood. He is, however, well read, cautious and candid, 

 and admits that he may be entirely mistaken. It is only too probable that this is the 

 case and that he has confused several blood conditions, one doubtless pathological, the 

 others histological. There is no need to quote from the paper at any length, but had 

 Dr. Foran been able to read a good account of blood fallacies and blood puzzles, I do 

 not think his paper, which he is frank enough to confess is by au amateur, would ever 

 have been penned. The pity is that he suggests this " piroplasm " is the cause of 

 blackwater fever. 



Observe the result. Dr. Gabrielle Breeze, of Tangiers, stimulated by Dr. Foran's 

 article, likewise plunges into print and describes bodies encountered by her in the blood 

 of blackwater fever patients both in fresh and stained preparations. Here again there is 

 little doubt but that these "spore-like" forms were derivatives of the blood itself, though 

 Dr. Breeze is possibly on surer ground when mentioning the curious X-bodies of Howell 

 and Horrocks. She, however, like Dr. Foran, is a careful worker, and concludes by 

 saying: "Of course I may be mistaken in my observations and supposition as to the Examples in 

 meaning of the bodies I saw, but unless we record what we see and are ready to prove '^'^™'- 



, , . . literature 



(.■<ic) ourselves mistaken, if we are so, much knowledge may die with us and our 

 labours in tropical lands fall short of their possibilities." It is a pity, however, if time 

 be wasted and other workers possibly misled. 



One cannot hope to deal with every source of fallacy which may occur any more 

 than one can hope to describe every type of puzzling and peculiar condition, but by 

 grouping together and illustrating in one paper the more frequent sources of error and 

 difficulty it may be possible to help those who are unfavourably situated for the obtaining 

 of advice either from books or from more experienced observers. 



