Risk factors for physical disability upon release from multidrug therapy in new cases of leprosy at a referral center in Brazil

The present study sought to investigate the risk factors for physical disability upon release from multidrug therapy (MDT) in new cases of leprosy, registered at a referral center in Brazil. This is a longitudinal and retrospective study that evaluated 260 patients. Multivariate analyses, using both the ordinal logistic regression, as well as the classification and regression tree (CART) algorithm were performed to determine the factors associated with physical disability upon release from treatment. The prevalence of disability did not differ significantly between diagnosis and release from treatment. Number of affected nerves and sensory impairment upon diagnosis were risk factors for disability at the end of MDT. The analysis using the CART algorithm resulted in the development of a clinical score to predict the risk of disability upon release from MDT. The decision tree may have a direct applicability in clinical practice for professionals dealing with leprosy, as it allows them to identify patients with a higher risk of physical disability through the use of simple and widely available clinical tests. This study also shows that the disability grade upon admission is the main risk factor for disability upon release from MDT. This result draws attention to the importance of early diagnosis in disability prevention

Usefulness of microvolt T-wave alternans for predicting outcome in patients with Chagas disease with implantable cardioverter defibrillators

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Reading of the Mitsuda test: comparison between diameter and total area by means of a computerized method

The Mitsuda test is a skin test based on the individual’s immune response through late and highly specific hypersensitivity reaction to the Mycobacterium leprae bacillus. A negative reaction identifies individuals who present a higher risk of becoming ill if exposed to M. leprae and, if they become ill, to develop the virchowian form of disease. The Mitsuda test reading is performed by means of a millimeter ruler. The dermatoscopy is a method that has not been used in the evaluation of cutaneous tests, although its use has increased in several areas. The study aimed to compare the results between the standardized reading and the total area of the Mitsuda test obtained by a computerized method which was structured by the association of digital dermatoscopy, the Dermatology Web system and the Image Tool 3.0 software. Data collection was performed at the Dermatology Outpatient Clinic of the Eduardo de Menezes Hospital, in Belo Horizonte, from November 2015 to August 2016. The sample consisted of 100 leprosy domiciliary contacts. There was an excellent agreement between the Mitsuda test (diameter and area), with a coefficient greater than 80%, and an excellent correlation with the Spearman’s correlation coefficient (0.936). The intraclass correlation coefficient indicated a low (0.219) but significant agreement between the two measurements. In conclusion, there is a significant correlation between the standardized reading and the total area of the Mitsuda test. Digital dermoscopy can be an alternative instrument of evaluation, allowing the computerization and recording of the Mitsuda test

Factors associated with the development of leprosy in Brazilian contacts: a systematic review

People who interact with leprosy patients in their environment, neighborhood, family, or social relationships are at risk to develop the disease. This systematic review investigated the risk and protective factors associated with the development of leprosy in Brazilian contacts. The studies were found in Cochrane Library, PubMed (MEDLINE), Embase, Virtual Health Library, grey literature and hand search until July 2021. The study selection, data extraction and quality assessment were independently performed by two investigators. The quality assessment was performed using the Newcastle-Ottawa Scale (NOS). This review was registered in PROSPERO (CRD42020160680). Seventeen articles fulfilled the inclusion criteria (n=544). The immunological and molecular factors, such as Anti-phenolic Glycolipid Antibodies (Anti-PGL-1) seropositivity, negative Mitsuda test, absence of Bacillus Calmette-Guérin (BCG) scar, positive Polymerase Chain Reaction (PCR) in blood; age and race; conviviality, education, contact time and type of contact, as well as elements related to the index case (bacilloscopic index; genetic conditions, family relationships), and some combined factors were shown to be relevant risk factors associated with the development of the disease in Brazilian leprosy contacts. The protective factors reported were the presence of one or more BCG scars, positive Mitsuda test, and education level. All selected studies were considered of high quality according to NOS. The knowledge of disease-related risk and protective factors provides the scientific basis for decision-making in the management of the disease in leprosy contacts

Immunoregulatory mechanisms in Chagas disease: modulation of apoptosis in T-cell mediated immune responses

Submitted by Nuzia Santos ([email protected]) on 2017-07-17T17:53:45Z No. of bitstreams: 1 Chaves_AnaThereza_Immunoregulatory mechanisms_IRR_2016.pdf: 12736177 bytes, checksum: 7182dae7e3675c77254aa3dd4157a0a9 (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2017-07-17T18:03:09Z (GMT) No. of bitstreams: 1 Chaves_AnaThereza_Immunoregulatory mechanisms_IRR_2016.pdf: 12736177 bytes, checksum: 7182dae7e3675c77254aa3dd4157a0a9 (MD5)Made available in DSpace on 2017-07-17T18:03:09Z (GMT). No. of bitstreams: 1 Chaves_AnaThereza_Immunoregulatory mechanisms_IRR_2016.pdf: 12736177 bytes, checksum: 7182dae7e3675c77254aa3dd4157a0a9 (MD5) Previous issue date: 2016Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, BrazilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, Brazil/Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Morfologia. Laboratório de Biologia das Interações Celulares. Belo Horizonte, MG, Brazil/Universidade Federal de Minas Gerais. Faculdade de Medicina Programa de Pós graduação em Medicina Tropical e Infectologia. Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, BrazilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Biomarcadores de Diagnóstico e Monitoração. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Morfologia. Laboratório de Biologia das Interações Celulares. Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Parasitologia. Laboratório de Imunologia e Genômica de Parasitos. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Fisiologia e Biofísica. Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Imunologia Celular e Molecular. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Parasitologia. Laboratório de Imunologia e Genômica de Parasitos. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Faculdade de Medicina Programa de Pós graduação em Medicina Tropical e Infectologia. Belo Horizonte, MG, Brazil.Laboratório de Imunologia Celular e Molecular, Centro de Pesquisas René Rachou, Fiocruz, Belo Horizonte, Brazil/Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais. Belo Horizonte, MG, Brazil/Universidade Federal de Ouro Preto. Ouro Preto, MG, Brazil.BACKGROUND: Chronic Chagas disease presents different clinical manifestations ranging from asymptomatic (namely indeterminate) to severe cardiac and/or digestive. Previous results have shown that the immune response plays an important role, although no all mechanisms are understood. Immunoregulatory mechanisms such as apoptosis are important for the control of Chagas disease, possibly affecting the morbidity in chronic clinical forms. Apoptosis has been suggested to be an important mechanism of cellular response during T. cruzi infection. We aimed to further understand the putative role of apoptosis in Chagas disease and its relation to the clinical forms of the disease. METHODS: Apoptosis of lymphocytes, under antigenic stimuli (soluble T. cruzi antigens - TcAg) where compared to that of non-stimulated cells. Apoptosis was evaluated using the expression of annexin and caspase 3(+) by T cells and the percentage of cells positive evaluated by flow cytometry. In addition activation and T cell markers were used for the identification of TCD4(+) and TCD8(+) subpopulations. The presence of intracellular and plasma cytokines were also evaluated. Analysis of the activation status of the peripheral blood cells showed that patients with Chagas disease presented higher levels of activation determined by the expression of activation markers, after TcAg stimulation. PCR array were used to evaluate the contribution of this mechanism in specific cell populations from patients with different clinical forms of human Chagas disease. RESULTS: Our results showed a reduced proliferative response associated a high expression of T CD4(+)CD62L(-) cells in CARD patients when compared with IND group and NI individuals. We also observed that both groups of patients presented a significant increase of CD4(+) and CD8(+) T cell subsets in undergoing apoptosis after in vitro stimulation with T. cruzi antigens. In CARD patients, both CD4(+) and CD8(+) T cells expressing TNF-α were highly susceptible to undergo apoptosis after in vitro stimulation. Interestingly, the in vitro TcAg stimulation increased considerably the expression of cell death TNF/TNFR superfamily and Caspase family receptors genes in CARD patients. CONCLUSIONS: Taken together, our results suggest that apoptosis may be an important mechanism for the control of morbidity in T. cruzi infection by modulating the expression of apoptosis genes, the cytokine environment and/or killing of effector cells

Regulatory T Cells Phenotype in Different Clinical Forms of Chagas' Disease

CD25High CD4+ regulatory T cells (Treg cells) have been described as key players in immune regulation, preventing infection-induced immune pathology and limiting collateral tissue damage caused by vigorous anti-parasite immune response. In this review, we summarize data obtained by the investigation of Treg cells in different clinical forms of Chagas' disease. Ex vivo immunophenotyping of whole blood, as well as after stimulation with Trypanosoma cruzi antigens, demonstrated that individuals in the indeterminate (IND) clinical form of the disease have a higher frequency of Treg cells, suggesting that an expansion of those cells could be beneficial, possibly by limiting strong cytotoxic activity and tissue damage. Additional analysis demonstrated an activated status of Treg cells based on low expression of CD62L and high expression of CD40L, CD69, and CD54 by cells from all chagasic patients after T. cruzi antigenic stimulation. Moreover, there was an increase in the frequency of the population of Foxp3+ CD25HighCD4+ cells that was also IL-10+ in the IND group, whereas in the cardiac (CARD) group, there was an increase in the percentage of Foxp3+ CD25High CD4+ cells that expressed CTLA-4. These data suggest that IL-10 produced by Treg cells is effective in controlling disease development in IND patients. However, in CARD patients, the same regulatory mechanism, mediated by IL-10 and CTLA-4 expression is unlikely to be sufficient to control the progression of the disease. These data suggest that Treg cells may play an important role in controlling the immune response in Chagas' disease and the balance between regulatory and effector T cells may be important for the progression and development of the disease. Additional detailed analysis of the mechanisms on how these cells are activated and exert their function will certainly give insights for the rational design of procedure to achieve the appropriate balance between protection and pathology during parasite infections