AFRICAN TRYPANOSOMIASIS 139 



The central canal of the cord may be dilated, but more often il is 

 occluded by cell proliferation. 



Sometimes there is haemorrhage of the cord vessels. 



These changes were not noted in a cured Tr\^pan()somiasis case 

 which died later from another disease. 



The lymphatic fj^latuls. 



Trypanosomes are often found in them. 



The lymphatic cells often change into cells of Marschalko. These 

 then change into morula cells. 



Endothelial cells of a lymphatic sinus proliferate, become phago- 

 cytic, containing lymphocytes, red cells and chromatin particles. 



The gland is congested. 



The fibrous tissue of the capsule and septa proliferate and become 

 thickened. 



When the inflammation subsides, the gland tissue becomes less 

 vascular, firm, hard and full of dense fibrous tissue. 



Secondary infection may occur and abscesses result. 



The lungs. 



These are hyperaemic often. 



They may show pneumonic compiicalions. 



The heart. 



There is small-celled infiltration in all its la\ers. 



Sometimes it shows haemorrhages. 



The liver and spleen. 



There is a thickening of the capsule. 



The spleen is congested and the trabecular thickened. 



The bone marrow. 



It is very cellular, vessels congested, hcTmorrhages. 



SYMPTOMATOLOGY. 



There are three stages : — - 

 (i) Incubation. 



(2) Febrile or glandular. 



(3) Cerebral. 



In all three the clinical manifestations are irregular in degree and 

 duration. 



INCUBATION. 



The time in man is not known. Probably two to three weeks, or it 

 may be less than ten days. Some individuals have not shown any 

 symptoms after being infected for five years. I had several patients 

 who had carried trvpanosomes for two vears and shn\\'ed no other 

 manifestations of the disease at <-ill. 



