The sensitivity of culture methods to detect experimental infections of Trypanosoma cruzi and comparison with xenodiagnosis
Neal, R.A.; Miles, R.A.
Revista do Instituto de Medicina Tropical de Sao Paulo 19(3): 170-176
1977
ISSN/ISBN: 0036-4665 PMID: 414342 Document Number: 116911
A study was made of new media for the cultivation of trypomastigotes of Trypanosoma cruzi from mouse blood. It was found that the best media were those of Warren or of Bone and Parent. 5 ml medium was used in a 20 ml bottle incubated at 26 deg , and examined after 2 and 6 weeks. Warren's medium became infected from as few as 10 trypomastigotes. A comparison was made with xenodiagnosis (using 11 3rd or 4th stage instars of Rhodnius prolixus) applied to Erythrocebus patas monkeys infected with the peru strain of T. cruzi. Culture in 3 bottles of Warren's medium, each inoculated with 0.3 ml heparinized blood, was superior to xenodiagnosis in detecting trypanosomes, but in chronic infections both methods should be used. Five media were compared for the ability to support growth initiated by low numbers of Trypanosoma cruzi trypomastigotes; the most suitable were those of L.G. Warren and of G. Bone & G. Parent. Further investigations with Warren's medium showed that between 10 and 20 trypomastigotes reliably give positive cultures. Comparative studies showed that overall blood culture in Warren's medium is superior to xenodiagnosis with Rhodnius prolixus Stal. For the detection of trypanosomes in the acute stage of infection it is the method of choice, but when infection is in the chronic phase, the use of both methods is required for maximum sensitivity.