94 TROPICAL MEDICINE AND HYGIENE 



last urine passed in this stage often contains no oxyhaemo- 

 globin, but methaemoglobin only, the urine changing 

 from a red-black to a dark brown colour. As the urine 

 clears the temperature falls to normal or subnormal, 

 Profuse sweating may occur several times in one day. 

 The change from the haemoglobinuric period to the 

 non - haemoglobinuric is less abrupt than would be 

 judged by mere superficial examination of the urine. 

 The haemolytic process has ceased, and the waste 

 products are being rapidly eliminated. As the hemo- 

 globin disappears the diuresis diminishes, so that even 

 when abundant fluid is supplied the rate of secretion 

 of urine may fall to much below normal. This is prob- 

 ably merely the result of the over-stimulation of the 

 renal cells, so that secretion becomes slow. If any 

 urine at all is passed, a fall in the rate of secretion to 

 less than half the normal is to be expected and should 

 cause no alarm, though fluid must still be supplied freely. 

 The rate of secretion in a favourable case soon increases. 

 The urine is clear and of normal colour, but contains 

 a small amount of albumin and some casts. The patient 

 remains in an extremely weak condition, and the anaemia 

 may show a slight increase, though the appearance of 

 the blood corpuscles is more natural. The temperature 

 may remain normal or commence to rise. After a day 

 or two the temperature rises, usually above normal, and 

 for several days there may be irregular pyrexia, secondary 

 fever. This varies a great deal in severity. In some 

 cases it is very slight, the temperature rising in the 

 evening to 100 F. or even less (figs. 28 and 29). More 

 frequently the nocturnal rises are to 101 and 102 F., 

 the temperature falling nearly to normal in the morning. 

 In other cases it is much more severe, and occasionally 

 there is fatal hyperpyrexia in this stage without any 

 recurrence of haemoglobinuria. The usual duration of 

 this stage is three to four days, and it may be protracted 

 to two or three weeks. The urine in this stage remains 

 free from haemoglobin and usually from albumin. No 



