338 



parasites bears no relation to the severity of the 

 symptoms. 



If necessary, dilute the blood (several c.c.) with 

 one per cent, sodium citrate solution, and centri- 

 fugalize ; carefully remove with a pipette some of the 

 superficial layers of the sediment, and examine with a 

 one-sixth inch lens fresh. If not found, the fluid is 

 poured off, some fresh citrate added, and the process 

 repeated three or four times.* 



2. Blood Changes. In uncomplicated cases of 

 sleeping sickness there is no anaemia (?). As regards 

 the leucocytes the changes are not constant. A large 

 mononuclear increase up to twenty to thirty per cent, 

 has been recorded^ and even higher values for native 

 blood. On the other hand the increase generally affects 

 the lymphocytes, which may reach values of fifty to sixty 

 per cent. It is probable that some of these are plasma 

 cells, but they have not been so far recorded. The 

 possibility of a mononuclear increase from trypanoso- 

 miasis should therefore be borne in mind in those cases 

 of malaria where no parasites are present, but trypanoso- 

 miasis in doubtful cases is most easily diagnosed by 

 gland puncture. The average values of a large number 

 of counts made by Greig and Gray give : red cells, 

 4,707,000; white cells, 11,000; large mononuclear, 

 twelve per cent. ; lymphocytes, thirty-eight per cent. ; 

 polynuclears, thirty-nine per cent. ; eosinophil, five 

 per cent. 



3. Gland Puncture. Sterilize the syringe and get 

 rid, as far as possible, of any fluid in the interior. 

 Puncture the posterior cervical glands and move the 

 point of the needle about in the substance of the 

 gland. Draw out the piston. Now detach the 

 barrel only. Next take out the needle. Then, 

 replacing the barrel eject the contents, best, into a 



* Koch recommends the frequent examination of stained films made as thick 

 as possible. 



