Evaluation of the parasitologic technics used in the diagnosis of human Trypanosoma gambiense trypanosomiasis in the Ivory Coast]

The investigators carried out a comparative evaluation of twelve or parasitological techniques used nowadays in the diagnosis of human trypanosomiasis and parasite isolation in the lymph fluid, blood and cerebro-spinal fluid (CSF). The tests were performed on 64 seropositive suspects selected with TESTRYP-CATT among 661 attendants examined at the Projet de Recherches Cliniques sur la Trypanosomiase (PRCT), Daloa, Côte-d'Ivoire. The study showed that the sensitivity of the different techniques varies between 17.2% (for CSF inoculation to Mastomys) and 84.5% (for the anion exchange centrifugation technique-mAECT). The classical techniques, says lymph fluid examination, direct blood examination and thick blood have a sensitivity of 58.6, 22.4 and 34.5% respectively. The most sensitive methods are lymph fluid examination, mAECT and double centrifugation of CSF (69%). The sensitivity increases up to 98.3% with the combination of two or three techniques. The combination of lymph fluid examination/mAECT/double centrifugation of CSF is either the most sensitive and the most suitable one for use in the field. The combination of lymph fluid examination and mAECT which detects 91.4% of the infected subjects is the most efficient. The authors discussed the results and recommended that similar study be done in field conditions to assess methods which either demonstrated better sensitivity and are more suitable for field use.