RESUMO
Chagas disease is caused by the parasite Trypanosoma cruzi. In humans, it evolves into a chronic disease, eventually resulting in cardiac, digestive, and/or neurological disorders. In the present study, we characterized a novel T. cruzi antigen named Tc323 (TcCLB.504087.20), recognized by a single-chain monoclonal antibody (scFv 6B6) isolated from the B cells of patients with cardiomyopathy related to chronic Chagas disease. Tc323, a ~323 kDa protein, is an uncharacterized protein showing putative quinoprotein alcohol dehydrogenase-like domains. A computational molecular docking study revealed that the scFv 6B6 binds to an internal domain of Tc323. Immunofluorescence microscopy and Western Blot showed that Tc323 is expressed in the main developmental forms of T. cruzi, localized intracellularly and exhibiting a membrane-associated pattern. According to phylogenetic analysis, Tc323 is highly conserved throughout evolution in all the lineages of T. cruzi so far identified, but it is absent in Leishmania spp. and Trypanosoma brucei. Most interestingly, only plasma samples from patients infected with T. cruzi and those with mixed infection with Leishmania spp. reacted against Tc323. Collectively, our findings demonstrate that Tc323 is a promising candidate for the differential serodiagnosis of chronic Chagas disease in areas where T. cruzi and Leishmania spp. infections coexist.
Assuntos
Doença de Chagas , Leishmania , Trypanosoma cruzi , Humanos , Simulação de Acoplamento Molecular , Filogenia , Doença de Chagas/diagnóstico , Anticorpos MonoclonaisRESUMO
Chagas disease reactivation in HIV-positive people is an opportunistic infection with 79 to 100% mortality. It commonly involves the central nervous system (CNS). Early treatment with trypanocidal drugs such as benznidazole (BNZ) is crucial for this severe manifestation of Trypanosoma cruzi infection. However, limited BNZ clinical pharmacology data are available, especially its concentration in the CNS. We report a series of HIV-positive patients undergoing treatment for T. cruzi meningoencephalitis, their clinical response, and cerebrospinal fluid (CSF) and plasma BNZ concentrations. Measurements were carried out using leftover samples originally obtained for routine medical care. A high-performance liquid chromatography/tandem mass spectrometry bioanalytical method designed for BNZ plasma measurements was adapted and validated for CSF samples. Six patients were enrolled in this study from 2015 to 2019. A total of 6 CSF and 19 plasma samples were obtained. Only three of the CSF samples had detectable BNZ levels, all under 1 µg/ml. Fifteen plasma samples had detectable BNZ, and 13 were above 2 µg/ml, which is the putative trypanocidal level. We observed BNZ concentrations in human CSF and plasma. CSF BNZ concentrations were low or not measurable in all patients, suggesting that the usual BNZ doses may be suboptimal in HIV-positive patients with T. cruzi meningoencephalitis. While drug-drug and drug-disease interactions may be in part responsible, the factors leading to low CSF BNZ levels remain to be studied in detail. These findings highlight the potential of therapeutic drug monitoring in BNZ treatment and suggest that the use of higher doses may be useful for Chagas disease CNS reactivations.
Assuntos
Doença de Chagas , Infecções por HIV , Meningoencefalite , Nitroimidazóis , Tripanossomicidas , Trypanosoma cruzi , Doença de Chagas/tratamento farmacológico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Meningoencefalite/tratamento farmacológico , Nitroimidazóis/uso terapêutico , Tripanossomicidas/uso terapêuticoRESUMO
Abstract Chagas Disease is caused by Trypanosoma cruzi. This infection is endemic in the Americas region. Neurological Chagas reactivation is diagnosed through the visualization of the parasite in the cerebrospinal fluid, blood, or tissue samples. Herein, we report the visualization of trypomastigotes by direct microscopic observation of a brain biopsy specimen and its preservation fluid (PF) in a paitient infected with VIH and T. cruzi. This easy and simple diagnostic method coupled with quantitative polymerase chain reaction can be used in all tissue biopsies and PF of T. cruzi seropositive patients, suspected of Chagas disease reactivation.
Assuntos
Humanos , Trypanosoma cruzi , Doença de Chagas/diagnóstico , Biópsia , Testes Diagnósticos de RotinaRESUMO
Chagas Disease is caused by Trypanosoma cruzi. This infection is endemic in the Americas region. Neurological Chagas reactivation is diagnosed through the visualization of the parasite in the cerebrospinal fluid, blood, or tissue samples. Herein, we report the visualization of trypomastigotes by direct microscopic observation of a brain biopsy specimen and its preservation fluid (PF) in a paitient infected with VIH and T. cruzi. This easy and simple diagnostic method coupled with quantitative polymerase chain reaction can be used in all tissue biopsies and PF of T. cruzi seropositive patients, suspected of Chagas disease reactivation.
Assuntos
Doença de Chagas , Trypanosoma cruzi , Biópsia , Doença de Chagas/diagnóstico , Testes Diagnósticos de Rotina , HumanosRESUMO
In Argentina scorpion stings are the leading cause of venom-related injury to human. Since the beginning of the 20th century Tityus trivittatus is found in Buenos Aires. Scorpion envenomation is a neurotoxic syndrome with local symptoms and systemic manifestations. It could develop cardiac failure, acute pulmonary edema, shock and death. Fortunately, most of the scorpion stings in adult people in Buenos Aires are mild envenomations. A retrospective, descriptive and cross sectional study based on data collected from medical records of patients followed between 1982 and 2013 were done. We compiled a total of 141 human scorpion stings and 115 arthropod captures: 88 T. trivittatus, 10 Bothriurus bonariensis and 17 missed data. The accidents occurred more frequently in the eastern and oldest neighborhoods of the city. Eighteen patients had mild systemic manifestation. There was not any death. Twelve patients received scorpion antivenom. Although recently there was a severe case in 5 years old boy and in some provinces in Argentina death have been reported, most of the envenomations are mild. We observed inadequate treatment in some patients; it is important training on the correct management and prevention of this envenomation.
En Argentina el escorpionismo es el principal envenenamiento por animales ponzoñosos. Desde comienzos del siglo XX, Tityus trivittatus ha sido descripto en Buenos Aires. El escorpionismo es una intoxicación que produce un síndrome neurotóxico con síntomas locales y manifestaciones sistémicas. Puede desencadenar insuficiencia cardiaca, edema agudo de pulmón, shock y muerte. Afortunadamente, la mayoría de los accidentes con escorpiones en adultos en Buenos Aires son intoxicaciones leves. Se realizó un estudio retrospectivo, descriptivo y transversal basado en información recolectada de las historias clínicas desde 1982 hasta 2013. Se recolectó información sobre un total de 141 intoxicaciones por escorpiones y 115 capturas de artrópodos: 88 T. trivittatus, 10 Bothriurus bonariensis y 17 sin identificar. Los accidentes sucedieron más frecuentemente en los barrios del este y más antiguos de la ciudad. Dieciocho pacientes tuvieron síntomas sistémicos leves. No hubo ninguna muerte. Doce pacientes recibieron antiveneno. La mayoría de los envenenamientos fueron leves, aunque recientemente se produjo un caso grave en un niño de 5 años y en algunas provincias se han registrado muertes. Hemos observado un tratamiento inadecuado en algunos pacientes por lo que consideramos que sería importante capacitar en el correcto manejo y prevención de este envenenamiento.