1274 



THE AFRICAN TRYPANOSOMIASES 



(nona). To make a definite diagnosis, the demonstration of 

 C. castellanii, C. gambiensis, or C. rhodesiensis in the body of the 

 patient is necessary. The following methods should be used: — 



1. Microscopical Examination of the Peripheral Blood from the 

 Finger or Ear. — This procedure is often a failure, even using thick 

 films. 



2. Scarification of the Erythematous Eruption and Examination of 

 Blood Films. — This method is more useful than the first, but may fail. 



3. Nabarro's Method. — Repeated centrifugahzation of 10 c.c. of 

 citrated blood, and examineition of the third sediment. The results 

 are good. 



4. Dutton-Todd's Method.- — Some citrated blood is centrifugalized 

 in small tubes and the leucocytic layer examined for trypanosomes. 



5. Greig-Grey's Method. — ^Aseptic puncture of the enlarged cervical 

 glands with a sterile syringe. The gland-juice is examined for 

 trypanosomes. This, from a practical point of view, is the most 

 valuable method. To Mott belongs the credit of having first sug- 

 gested the search for trypanosomes in the lymph glands as a diag- 

 nostic method. Balfour has devised a 'gland-holder,' which is 

 useful in some cases. 



6. Castellani's Method. — Centrifugahzation for fifteen minutes of 

 10 c.c. of cerebro-spinal fluid, aseptically removed by means of 

 lumbar puncture. The sediment is examined for trypanosomes 

 by making fresh and stained preparations. The result is almost 

 constantly positive in the sleeping-sickness stage, but negative, as 

 a rule, in the first stage of the malady. 



The technique to perform lumbar puncture is as follows: The patient may 

 be given chloroform, but usually a local anajsthetic spray is sufficient. Lay 

 the patient on the right or left side; flex the thighs on the abdomen. Then 

 make the skin of the lumbar region aseptic, and, feeling with the tip of the 

 finger the position of the laminae, thrust the sterile needle between the laminae 

 of the third and fourth lumbar vertebrae, ^ inch from the median line, obliquely 

 outwards and forwards into the canal. The fluid will escape, and can be 

 collected in a sterile tube. After withdrawing the needle, the area should 

 be covered with an aseptic pad and bandage. 



7. Inoculation of Susceptible Animals. — ^Ten c.c. or 20 c.c. of blood 

 are aseptically removed from a vein and inoculated into sus- 

 ceptible animals, or 10 c.c. of cerebro-spinal fluid may be inocu- 

 lated. The animals most suitable are monkeys, guinea-pigs, and 

 dogs. The most suitable monkeys, according to Thiroux and 

 d'Anfreville, are those of the species Cercopithecus ruber, while 

 some other species — e.g., C . fuliginosus — are almost refractory. 



The following biological phenomena and reactions may sometimes be of 

 diagnostic value: — 



I. AutO' Agglutination. — In many cases of sleeping sickness, in wet pre- 

 parations of blood examined microscopicall}'' with a low power, the red 

 corpuscles are not evenly distributed, nor are they arranged in rouleaux, 

 but are clumped together — ' agglutinated ' — in irregular masses. This 

 appearance is not specific of trypanosomiasis, having been found in cases 

 of filariasis, malaria, syphilis, and yaws. 



