Surra : Rot. 635 



Pathology and Lesions. The pathology of the disease consists 

 in the rapid destruction of the red blood globules by the trypano- 

 somata. It is a form of rapidly advancing pernicious anaemia 

 due to the great and active voracity of the trypanosoma. The 

 swarming of the trypanosoma in the blood at the period of the 

 relapse and the absence of the mature form in the intervals is re- 

 markable. The trembling movement in the blood at the period 

 of swarming results from their prodigiously active movements. 

 The red globules may assume various forms, crenate, echinated, 

 (Ranking), and more or less broken up or disintegrated, their 

 numbers steadily decrease, leaving the blood thin and watery 

 with rusty serum and yellow (icteric) staining of the white 

 tissues, even the bones. Encrease of white globules, actual or 

 relative, has been a marked feature (always present in typical 

 cases, Burke). 



Petechiae are especially common on the conjunctiva, vaginal 

 mucosa, endocardium, and less marked in the nose, mouth, and 

 serosae. 



CEdemas are common, yellowish, gelatinoid, exudates at the base 

 of the heart, subcutem, between the muscles of the limbs or else- 

 where, and as effusions into the pleurae pericardium or peritoneum. 



Distinct blood extravasations have been noted beneath the en- 

 docardium. 



' The spleen is often enlarged, excessively so if death occurred 

 during a paroxysm. The lymph glands are swollen and appear 

 dropsical. 



The whole body is emaciated and shrunken, the visible (un- 

 petechiated) mucosae are pale and bloodless, often yellow, yet 

 rigor mortis is well marked. 



Gastric ulcers are common (Steel, Burke, G. W. Evans) ap- 

 parently preceded in many cases by capillary embolism con- 

 gestion and degeneration. Intestinal, congestions are frequent 

 (Steele, Burke), but ulcers are rare (Geo. H. Evans). 



The liver may be normal (Griffith Evans), or especially during 

 a paroxysm (I^ingard) congested, inflamed and enlarged. The 

 pancreas is usually normal. 



The kidneys are petechiated, congested, cedematous, or the 

 seat of blood extravasations. 



Instances have been noted of cerebral and meningeal oedema 



