66 REVIEW TROl'ICAIi MEDICINE, ETC. 



Fevers. Under this heading one considers those obscure and indefinite febrile 

 processes in the tropics to wliich so much attention has been recently directed, and on 

 which, no doubt, a great deal of work still remains to be done. 



In the first place, however, one may quote Sutherland's valuable paper' on the method 

 of approaching a case of fever for the purpose of forming a diagnosis : — 



The cause (he says) must bo infective or non-iufectivo. If iafective, look fiir a p.irasite which must be either 

 (a) Animal (rimoelia, piroplasma, Leishman-Donovan l)o<ly, trypanosouie, worm enil)ryo or worm), or (h) Vegetable 

 (coccus, bacillus, spirillum or fungus). 



The infection must be cither (a) of the general circulation, (b) of the spleen or lymph circulation, (c) a local 

 infection of some mucous surface of entrance iulo, or exit from, the body, (d) an intoxication from without. 

 Methods of procedure : — 



1. Is it a general infection? i.e. of the circulating blood. If so, the parasite must be found in the 

 circulation, or evidence must be obtained of its having been there. 



Examine fresh blood at room temperature and on warm stage. 



Examine blood films stained and with or without decoloration of the red cells. 



A negative finding is inconclusive, for (1) the parasite m.ay not be in the circulation at the time, e.g. the filaria 

 embryo, or (2) the parasites may be few in number ; and in any case one can hardly expect that a single drop of 

 blood will always contain a parasite. Remember the value of drawing off a large quantity of blood, citrating it 

 and incubating it at body temperature for some days. Sometimes parasites can only be found by making cultures 

 from the blood or by making inoculations into susceptible animals. 



If parasite not present, evidence of its previous presence shown, as in malaria, by broken up red cells and free 

 pigment taken up by the leucocytes. The spirochsete of relapsing fever also leaves behind it iu the blood, in the 

 apyrexial periods, small coccus-like bodies. 



(It is possible that in human spirochaetal infections endoglobular bodies will yet be 

 discovered similar to those found in the blood of fowls and geese. — A. B.) 



Changes in the number of leucocytes, or in the differential count, are not distinctive. Taken with other signs, 

 however, an increase of the small lymphocytes at the expense of the polymorphonuclears would point to Dengue 

 fever. This point is not mentioned by Sutherland, but vide notes under " Blood " and " Dengue." 



When the above methods fail to reveal a parasite or signs of its presence in the circulating blood, we are 

 justified in assuming that the infection is not a septicaemia. 



2. Is it a spleen or lymph infection ? 



Remember the circulating blood is inimical to microbes which take refuge iu the lymph stream, and that the 

 spleen, lymphoid tissues and lymph glands are the filtering media of the blood. If the parasite be in the spleen 

 or in the lymph circulation its toxins must pass into the blood. Evidence of this is seen in leucocytosis or 

 lymphocytosis. The latter is specially distinctive of spleen and lymjjh infections, particularly when the 

 lymphocyte increase is of the large mononuclear variety. 



In marked relative increase of large mononuclears, suspect malaria or kala-azar, but less marked increase 

 occurs in enteric, tuberculosis and possibly syphilis. 



When parasite is in spleen, look for spenomegaly. 



Splenic puncture may be required, and reveals Leishman-Donovan bodies, malaria parasites, bacilli of anthrax, 

 typhoid or micrococcus of Malta fever. 



Presence of macrophages evidences splenic irritation. Absence of parasites and macrophages implies that 

 there is no infection of the spleen. 



As regards a parasite in the lymph circulation, consider the tonsil, vermiform appendix and superficial lymph 

 glands. Look out for enlargement ; or, in the case of the lymph sacs, effusion. Puncture of the tonsil or enlarged 

 gland may reveal the parasite. Some infections, i.e. of Peyer's patches, deep lymph glands, etc., do not betray 

 their presence, and are considered under local infection. 



The parasite m.ay be found in lymph sac effusions or, if these are sterile, the agglutination test may reveal the 

 presence of tubercle, or a guinea pig may be inoculated. 



[Here one may add that the ophthalmo-reaction would now be tried both for tubercle 

 (Calmette) and typhoid (Chantemesse). — A. B.] 



In all doubtful cases where the blood examination shows leucocytosis or lymphocytosis, where there are no 

 physical signs and whore spleen puncture is negative, lumbar puncture should be made to see if there be effusion 

 into the meningeal lymph sac. Signs of exudation (as distinct from transudation) are positive, and the discovery 

 of the parasite completes the diagnosis. When the exudate is sterile the case is likely to be one of tuberculosis, and 

 confirmation is to be sought by the agglutination test and by inoculation into guinea pigs. 



It is here that one may insert a note on the diagnosis of a condition not mentioned by 

 Sutherland, and indeed only very recently brought to notice in India by Eoberts and 

 Bhaudarkar, namely Acute Tuberculous Fever. This will be mentioned later on. Here we 



' Sutherland, O., in " Enteric Fever in India, etc." Roberts, E., Calcutta. 



