244 



In a series of cases examined by ourselves in 

 Nyassaland we found malaria parasites only in 12*5 per 

 cent., but, as we have already shewn, we have two 

 further tests for a malarial infection : 



(1) The increase in the percentage of large 



mononuclear leucocytes. 



(2) The presence of pigmented large mono- 



nuclear leucocytes. 



By using these tests we were able to prove that 937 

 per cent., not 12*5 per cent., of our cases were due to 

 a malarial infection. 



Further, in the only case of blackwater fever seen 

 by us before the onset of haemoglobinuria, 'parasites 

 were present in abundance ; afterwards they rapidly 

 disappeared. 



EXAMINATION OF THE URINE IN BLACKWATER 

 FEVER 



1. Before the attack (if possible) examine for 

 albumen, urobilin, reducing bodies, etc. 



2. Examine so-called * high-coloured ' urines. 

 As a rule these do not shew bile pigment. 



3. Examine urine during an attack for methae- 

 moglobin (or haematin), oxyhaemoglobin, urobilin, 

 bile pigment (unusual), bilirubin crystals, haemoglobin 

 casts, granular or hyaline casts, blood cells (rare). 



4. Centrifugalize the urine. Examine the clear 

 layer (as in 3), and make films of the sediment. 



The sediment may contain hyaline and granular 

 casts stained with" haemoglobin. The mass of the 

 sediment, however, consists of masses of haemoglobin 

 of a yellowish-red colour. 



