Follow-up of an Asymptomatic Chagas Disease Population of Children after Treatment with Nifurtimox (Lampit) in a Sylvatic Endemic Transmission Area of Colombia

Abstract

BackgroundChagas disease is an anthropozoonosis caused by Trypanosoma cruzi. Two drugs are currently used for the etiological treatment of the disease: Nifurtimox (Lampit) and Benznidazole. This study presents a quasi-experimental trial (non-control group) of sixty-two patients who were treated for Chagas disease with Nifurtimox (Lampit), and were then followed for 30 months post-treatment. The safety of Nifurtimox (Lampit) for Chagas disease in this group of children primarily between 4 and 19 years old was also evaluated.Materials and methodsThe 62 patients included in the study were selected when resulted seropositive for two out of three fundamentally different serological tests. All children were treated during two months according to protocols established by WHO. Monitoring was performed every twenty days to evaluate treatment safety. In 43 patients, two different serological tests: ELISA and IFAT; and two parasitological tests: blood culture, and real time PCR, (qPCR) were performed to assess therapeutic response, defined as post-treatment serological negativization.Principal findingsAll patients completed the treatment successfully, and six patients abandoned the post-treatment follow-up. Adverse effects occurred in 74% of patients, but only 4.8% of cases required temporary suspension to achieve 100% adherence to the 60-day treatment, and all symptoms reverted after treatment completion. Both parasite load (measured through qPCR) and antibodies (ELISA absorbance) evidenced a significant median reduction 6 months after treatment from 6.2 to 0.2 parasite equivalents/mL, and from 0.6 to 0.2 absorbance units respectively (p<0.001). Serological negativization by ELISA was evident since 6 months post-treatment, whereas by IFAT only after 18 months. Serological negativization by the two tests (ELISA and IFAT) was 41.9% (95%CI: 26.5–57.3) after 30 months post-treatment. qPCR was positive in 88.3% of patients pre-treatment and only in 12.1% of patients after 30 months. Survival analysis indicated that only 26.3% (95%CI: 15.5–44.8) persisted with negative qPCR during the whole follow-up period.ConclusionsNifurtimox was very well tolerated and successfully reduced parasite load and antibody titers. Re-infection, lysed parasites or a lack of anti-parasitic activity could explain these persistently positive qPCR cases.

Enfermedad de Chagas del sistema nervioso central en un paciente con SIDA demostrada por métodos cuantitativos moleculares

“…Así, las 1.400 copias/mL de T. cruzi detectadas en nuestro paciente en el compartimento sanguíneo están en concordancia con estos estudios. Las mediciones cuantitativas parasitarias por RPC en sangre también han sido utilizadas en el seguimiento de pacientes tratados por enfermedad de Chagas 30 . En contraste, la detección parasitaria cuantitativa por RPC ha sido muy poco aplicada en muestras de LCR 10 .…”

Tripanosomiasis americana, una mirada desde el tratamiento

“…Estos compuestos oxidativos son producidos gracias a la enzima superóxido dismutasa, que es la responsable de la reducción de los grupos nitro; estos radicales en presencia de hierro forman un fuerte radical hidroxilo oxidante e incrementan la producción de especies reactivas de oxígeno, que finalmente van a llevar a un estrés oxidativo en el parásito. No obstante, el efecto oxidativo nocivo de estos compuestos resultantes no se limita al parásito, sino que afecta en igual proporción a las células de los mamíferos, lo que lleva al desarrollo de los efectos adversos de estos medicamentos (12,18) .…”

Padronização e validação de dois sistemas de amplificação quantitativa para a detecção do DNA mitocondrial e nuclear de Trypanosoma cruzi, em amostras sanguíneas e teciduais de camundongos Swiss infectados

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