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Vol.2 , No. 3, Publication Date: Jun. 11, 2015, Page: 20-29
 and immuno-histopathological methodologies in order to detect changes in the progression of the infection and to estimate the efficacy of the drug effect with the intention of establishing a criterion of cure for Chagas disease. Systematic observations at different time post primary infection revealed the degree of negative conversion recorded by each of the used tests and the tissular persistence of T. cruzi in 40% of the study patients. At the endpoint evaluation, four groups of individuals at different clinical conditions were recognized from the initially selected acute patients. These included typical chronic chagasic patients (35%), individuals with subclinical or inapparent infection (35%), symptomatic seronegative patients showing persistence of T. cruzi-tissue form (8%) and clinically cured patients (22%). Therefore, the here reached criterion of Chagas disease cure after a long-term evaluation with reliable methods involve those asymptomatic patients showing consistently negative sero-parasitological and molecular results for circulating parasites, as well as non-signal of T. cruzi tissue-form persistence. Statistical comparison between benznidazole-treated and untreated patients revealed no significant differences (P>0.05), neither in the recognized groups nor in the used methods. These results led us to conclude that therapeutic effect of benznidazole was unsatisfactory due to fails to eliminate T.cruzi-tissue form, which persisted for long periods in primary infected patients, raising doubts on its use as the drug of election for Chagas disease specific therapy.&picture=http://www.aascit.org/aascit/decorators/img/journal/906.jpg)
| [1] | Néstor Añez, Center for Parasitological Research “J.F.Torrealba”, Faculty of Sciences, University of Los Andes, Merida, Venezuela. |
| [2] | Gladys Crisante, Center for Parasitological Research “J.F.Torrealba”, Faculty of Sciences, University of Los Andes, Merida, Venezuela. |
| [3] | Agustina Rojas, Center for Parasitological Research “J.F.Torrealba”, Faculty of Sciences, University of Los Andes, Merida, Venezuela. |
| [4] | Sonia Araujo, Laboratory of Experimental Parasitology, Department of Biology, Faculty of Sciences, University of Los Andes, Merida, Venezuela. |
| [5] | Antonina Liuzza, General Hospital “Luis Razetti”, Dentistry Unit, Barinas, Venezuela. |
| [6] | Johana Mesa, General Hospital “Luis Razetti”, Dentistry Unit, Barinas, Venezuela. |
| [7] | Henry Parada, General Hospital “Luis Razetti”, Cardiological Unit, Barinas, Venezuela. |
A long-term follow-up study was carried out in acute chagasic patients evaluated from 1 to 23 year after receiving benznidazole treatment. Evaluation was performed combining clinical, serological, parasitological, molecular (Polymerase Chain Reaction, PCR) and immuno-histopathological methodologies in order to detect changes in the progression of the infection and to estimate the efficacy of the drug effect with the intention of establishing a criterion of cure for Chagas disease. Systematic observations at different time post primary infection revealed the degree of negative conversion recorded by each of the used tests and the tissular persistence of T. cruzi in 40% of the study patients. At the endpoint evaluation, four groups of individuals at different clinical conditions were recognized from the initially selected acute patients. These included typical chronic chagasic patients (35%), individuals with subclinical or inapparent infection (35%), symptomatic seronegative patients showing persistence of T. cruzi-tissue form (8%) and clinically cured patients (22%). Therefore, the here reached criterion of Chagas disease cure after a long-term evaluation with reliable methods involve those asymptomatic patients showing consistently negative sero-parasitological and molecular results for circulating parasites, as well as non-signal of T. cruzi tissue-form persistence. Statistical comparison between benznidazole-treated and untreated patients revealed no significant differences (P>0.05), neither in the recognized groups nor in the used methods. These results led us to conclude that therapeutic effect of benznidazole was unsatisfactory due to fails to eliminate T.cruzi-tissue form, which persisted for long periods in primary infected patients, raising doubts on its use as the drug of election for Chagas disease specific therapy.
Keywords
Chagas Disease, Follow-up, Persistence, Treatment, Cure Criterion
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