Severe Cases of COVID-19 and High Association with Causes of Immune Dysregulation: A Systematic Review.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus responsible for coronavirus 2019 (COVID-19), which was declared a pandemic in March 2020 by the World Health Organization due the rapid spread representing a global health crisis. The disease is characterized by a wide clinical spectrum ranging from asymptomatic forms until severe viral pneumonia, which can to evolve to severe acute respiratory syndrome, especially in elderly patients and/or with comorbidities. An efficient assembly of the immunological response of the patients becomes fundamental against SARS-CoV-2 infection and it has been demonstrating a significant relationship between the severity of the disease and expression profile of the immune cells and the levels of pro-inflammatory cytokines. This review aims to presents the main immunological mechanisms developed during the infection by SARS-CoV-2 in the evolution of the severe cases of COVID-19. The immune dysregulation of the Th1 cellular response standard, the instability in the production of neutralizing antibodies by plasma B cells, the difference in tropism of CD8+ T cells against virus proteins in early infection, late infection and reinfections, dynamic of alveolar macrophages and pulmonary innate lymphoid cells (TCR γδ) of the natural imune response and the high level of pro-inflammatory cytokines can determine the main cause of breath tissues damages and, consequently, a greater severity of the disease. Therefore, a complete understanding of the main immunological changes involved in SARS-CoV-2 infection can identify possible biomarkers in the evaluation of early prognosis of the severe cases of COVID-19, making possible better therapeutic success to the patients.

Assessment of rSodC, rPknG, rNanH, and rSpaC as Antigens for Diagnostic Tools Against Caseous Lymphadenitis.

Corynebacterium pseudotuberculosis is a bacillus that causes caseous lymphadenitis in small ruminants, leading to great losses to rural producers; thus, an efficient diagnosis is necessary for using disease control measures. This study aimed to evaluate the antigenic potential of four C. pseudotuberculosis recombinant proteins (rSodC, rPknG, rNanH, and rSpaC) against sera of goat and sheep experimentally infected with one of three different C. pseudotuberculosis strains. Goats were infected with CAP76 or CAP21 strain (n = 10), sheep with VD57 strain (n = 6), and a group of not-infected animals (goats and sheep) were kept as a healthy control (healthy n = 12). Sera were collected at 0, 14, 60, 90, 180, or 190 days after inoculation for antigenicity testing using Western blotting and enzyme-linked immunosorbent assay (ELISA) techniques. Cross-reactivity tests with recombinant proteins were performed in goat serum experimentally vaccinated with Nocardia sp. or Rhodococcus equi bacterin. The rSodC protein showed discriminatory antigenic reactivity with a statistically significant difference against three different C. pseudotuberculosis strains evaluated in goats and sheep samples, while rPknG showed statistical significance only against two C. pseudotuberculosis strains evaluated in goats. rSodC was proved to be a strong candidate as a tool for diagnosis of C. pseudotuberculosis infection, once it was able to recognize antibodies against all strains evaluated in goats and sheep.

Determining reference ranges for immunological cells of healthy indigenous individuals from a region in Brazil.

Morais et al. conducted a pioneering study with Brazilian indigenous populations to determine reference values for immunologic cells from healthy adult individuals. The main findings included a higher relative median for T lymphocyte subsets in females than males, and T CD3+, T CD4+, and T CD8+ relative values were statistically different when compared with Brazilian populations from other Brazilian regions. The relative medians of CD3+, CD4+, and CD8+ T cells were significantly higher in women than in men in a healthy indigenous population. Demographic and ethnic diversity of the Brazilian population can be associated with quantitative modifications in the immunologic cells of healthy individuals. OBJECTIVE: The establishment of reference values for a subset of leukocytes is common in clinical practice, and ethnic variations are strongly associated with disease development. In Brazil, indigenous people are vulnerable to infections, and few studies have described the health and disease conditions of this population. This study aimed to provide reference values for immunological cell subsets in indigenous Brazilians living in the state of Mato Grosso do Sul. METHODS: Flow cytometry and 4-color combinations of monoclonal antibodies were used to characterize cells. A total of 115 healthy adults, mostly females (72%), were included in the study. The results are presented as mean and median (2.5%-97.5% percentiles) for T and B lymphocytes, CD4+ T cells, CD8+ T cells, Natural Killer cells, monocytes, and dendritic cells, providing an average immunological profile for the population in question. RESULTS: The relative medians of CD3+, CD4+, and CD8+ T cells were significantly higher in women than in men in a healthy indigenous population. CONCLUSION: To our knowledge, cell reference data from indigenous Brazilians are unknown in the literature. The immune cell results presented in this pioneering study will contribute to the clinical and laboratory evaluation of the Brazilian indigenous population, especially given the important differences when compared with other Brazilian ethnic groups.

The Association of Bacterin and Recombinant Proteins Induces a Humoral Response in Sheep against Caseous Lymphadenitis.

In this study, we investigated the capacity of the recombinant proteins SpaC, NanH, SodC, and PLD of C. pseudotuberculosis to trigger protective humoral and cellular immune responses against experimentally induced C. pseudotuberculosis infection in sheep. The antigens were produced in a heterologous system and were purified by affinity chromatography. Nine sheep were randomly divided into three groups, which were immunized as follows: Group 1 (control)-a mix of adjuvants composed of the inactivated T1 strain of C. pseudotuberculosis and commercial Montanide™ISA 61 VG (T1M); Group 2-rSpaC, rSodC, rPLD, and T1M; Group 3-rNanH, rSodC, rPLD, and T1M. All groups were immunized twice (on days 0 and 30) and challenged on day 90 of the experiment. Humoral and cellular immune responses were evaluated by Enzyme-Linked Immunosorbent Assay (ELISA) to quantify the IgG antibodies and interferon-gamma (IFN-y). Both vaccine formulations with recombinant proteins (groups 2 and 3) could induce a significant humoral IgG immune response in sheep. The proteins rSodC, rPLD, and rNanH were more immunogenic, inducing significant levels of IgG antibodies after the first dose of the vaccine or after the challenge, maintaining constant levels until the end of the experiment. However, it was not possible to differentiate between the cellular responses induced by the vaccines. This lack of effectiveness points toward the need for further studies to improve the efficacy of this subunit-based vaccine approach.

Natural killer cell receptor and HLA-C gene polymorphisms among patients with hepatitis C: a comparison between sustained virological responders and non-responders.

BACKGROUND/AIMS: Killer cell immunoglobulin-like receptors (KIR) are involved in the activation/inhibition of NK cells through an interaction with HLA class I molecules on target cells. Our study aimed to evaluate the association between KIR gene polymorphisms and the response of patients with CHC to antiviral therapy. METHODS: We compared the frequency of KIR genes, as well as that of compound KIR/HLA-C genotypes, between groups of patients with CHC who presented a sustained virological response (n=66) and who were non-responders to a combination of pegylated or standard interferon and ribavirin (n=101). KIR and HLA-C genotyping were performed using commercial kits. RESULTS: We detected a greater frequency of the KIR2DL5 gene among non-responders to antiviral therapy compared with sustained virological responders (68.3 vs. 40.9%) (P<0.001). We used multiple logistic regression analysis to determine the association between therapy response and the presence of KIR2DL5, after a control for potentially confounding variables (genotype, alcohol, fibrosis, gender, age, ethnic background and route of HCV infection). The results confirmed the strong association between the presence of KIR2DL5 and the non-response to antiviral treatment (P=0.001). CONCLUSIONS: Host genetic factors may be associated with a non-response to antiviral therapy. KIR2DL5 is a candidate gene involved in immunomodulation associated with non-response to antiviral therapy.

Frequency and factors associated with Toxoplasma gondii infection in pregnant women and their pets in Ilhéus, Bahia, Brazil.

INTRODUCTION: Toxoplasmosis is an asymptomatic disease that can lead to systemic disease in the fetus of pregnant women with primary infection. This study aimed to determine the prevalence of toxoplasmosis, associated factors, and correlation between the serology of pregnant women and their pets, in the municipality of Ilhéus, Bahia, Brazil. METHODS: This cross-sectional study was conducted in 196 pregnant women and their cats or dogs (n=89). Semi-structured interviews were conducted and serum samples from the pregnant women were tested to detect IgM and IgG antibodies against Toxoplasma gondii, and avidity tests were performed for IgM-positive samples. The serum collected from pets were tested for IgG antibodies, and IgM antibodies in cats. A non-conditional logistic regression analysis was performed to identify infection-associated factors. RESULTS: IgG and IgM antibodies were detected in 67.9% (133/196) and 1.5% (3/196) samples, respectively, for women with an avidity of over 60%. Age ≥ 25 and the presence of cats in the vicinity were found to be associated with infection, while the level of education and previous orientation toward prevention of toxoplasmosis were protective factors in pregnant women. IgG antibodies were detected in 46.1% (41/89) of the animals, and cats were found to be negative for IgM. For the animals, age ≥ 1 year was a factor associated with infection. There was no correlation between serology of the pregnant women and the animals (p=0.15). CONCLUSIONS: An elevated prevalence of toxoplasmosis was detected in the region. Therefore, the adoption of preventive measures by public healthcare bodies is recommended.

Rapid molecular test for tuberculosis: impact of its routine use at a referral hospital.

OBJECTIVE: To evaluate the impact of the use of the molecular test for Mycobacterium tuberculosis and its resistance to rifampin (Xpert MTB/RIF), under routine conditions, at a referral hospital in the Brazilian state of Bahia. METHODS: This was a descriptive study using the database of the Mycobacteriology Laboratory of the Octávio Mangabeira Specialized Hospital, in the city of Salvador, and georeferencing software. We evaluated 3,877 sputum samples collected from symptomatic respiratory patients, under routine conditions, between June of 2014 and March of 2015. All of the samples were submitted to sputum smear microscopy and the Xpert MTB/RIF test. Patients were stratified by gender, age, and geolocation. RESULTS: Among the 3,877 sputum samples evaluated, the Xpert MTB/RIF test detected M. tuberculosis in 678 (17.5%), of which 60 (8.8%) showed resistance to rifampin. The Xpert MTB/RIF test detected M. tuberculosis in 254 patients who tested negative for sputum smear microscopy, thus increasing the diagnostic power by 59.9%. CONCLUSIONS: The use of the Xpert MTB/RIF test, under routine conditions, significantly increased the detection of cases of tuberculosis among sputum smear-negative patients.

Interferon-gamma release assay performance in northeastern Brazil: influence of the IFNG+874 A>T polymorphism.

INTRODUCTION: Latent tuberculosis infection diagnosis based on the release of interferon-gamma in cultures of peripheral blood cells stimulated with Mycobacterium tuberculosis antigens has replaced the tuberculin skin test in many countries with low tuberculosis prevalence. The IFN-γ production can be influenced by genetic polymorphisms, of which the IFNG+874 (rs62559044) locus is the most studied. We investigated the possible influence of the IFNG+874 A/T polymorphism on interferon-gamma test performance. METHODS: Patients diagnosed with pulmonary tuberculosis (75), volunteers with positive tuberculin skin test (70) and healthy volunteers with negative tuberculin skin test and no history of contact with tuberculosis (57) were evaluated regarding the IFNG+874 genotype and the IFN-γ levels in whole blood cultures performed using an interferon-gamma commercial kit (QuantiFERON-TB® Gold In-Tube). RESULTS: IFN-γ production was not influenced by the IFNG+874 genotype, regardless of antigen or mitogen-based stimulation, which suggests that other genes may influence IFN-γ production in response to mycobacteria. The IFNG+874 polymorphism was found to exert no influence over QFT-IT test sensitivity in our study. CONCLUSIONS: The IFNG+874 polymorphism was not shown to influence QuantiFERON-TB® Gold In-Tube test performance in an admixed population from northeastern Brazil.

In vivo and in vitro expression of five genes involved in Corynebacterium pseudotuberculosis virulence.

Caseous lymphadenitis (LC) is a chronic contagious disease caused by Corynebacterium pseudotuberculosis, which mainly affects goats and sheep. Vaccination is an effective but not yet well-established method, partly due to a lack of knowledge surrounding the most effective immunoprotective components. The present study aimed to quantify and compare the in vivo expression of genes pld (phospholipase D), cpp (CP40), nanH (neuraminidase H), sodC (superoxide dismutase C) and spaC (adhesin) using qRT-PCR, with the respective expression in vitro. Caseous material of abscesses removed from five animals was cultured, with colonies suggestive of C. pseudotuberculosis identified. RNA extraction was performed on these samples, as well as on the respective pellets derived from liquid cultures brain heart infusion. After evaluating RNA integrity, complementary DNA was synthesized, followed by the relative quantification each of the genes of interest. Mean mRNA expression of the five genes found in abscesses and in cultures differed significantly, with respective values of: nanH 811.50 ± 198.27 and 359.35 ± 75.45 (p = 0.009); cpp 856.31 ± 385.11 and 154.54 ± 94.34 (p = 0.0039); plD 922.70 ± 450.73 and 212.41 ± 153.10 (p = 0.016); sodC 1,293.53 ± 564.75 and 223.63 ± 145.58 (p = 0.016); spaC 1,157.10 ± 525.13 and 214.26 ± 125.70 (p = 0,016). Expression was observed to be 6-8 times higher in abscesses than in cultures, Indicative that is a genetic expression of the in vitro bacterium exists, yet in vivo has a greater magnitude corroborating to one of these virulence factors in the pathogenesis of LC.

Determining reference ranges for immunological cells of healthy indigenous individuals from a region in Brazil

ABSTRACT Objective The establishment of reference values for a subset of leukocytes is common in clinical practice, and ethnic variations are strongly associated with disease development. In Brazil, indigenous people are vulnerable to infections, and few studies have described the health and disease conditions of this population. This study aimed to provide reference values for immunological cell subsets in indigenous Brazilians living in the state of Mato Grosso do Sul. Methods Flow cytometry and 4-color combinations of monoclonal antibodies were used to characterize cells. A total of 115 healthy adults, mostly females (72%), were included in the study. The results are presented as mean and median (2.5%-97.5% percentiles) for T and B lymphocytes, CD4+ T cells, CD8+ T cells, Natural Killer cells, monocytes, and dendritic cells, providing an average immunological profile for the population in question. Results The relative medians of CD3+, CD4+, and CD8+ T cells were significantly higher in women than in men in a healthy indigenous population. Conclusion To our knowledge, cell reference data from indigenous Brazilians are unknown in the literature. The immune cell results presented in this pioneering study will contribute to the clinical and laboratory evaluation of the Brazilian indigenous population, especially given the important differences when compared with other Brazilian ethnic groups.

Diagnosis of canine brucellosis by ELISA using an antigen obtained from wild Brucella canis.

An indirect ELISA test was developed for the diagnosis of Brucella canis infection in dogs. A bacterial whole cell extract was used as a solid phase antigen, using B. canis isolated from an infected animal. Sera from culture-positive and healthy negative animals were used as internal reference controls. The cut-off point was determined by a mathematical formula for a statistically valid value, which defined the upper prediction limit, based on the upper tail of the t-distribution of 21 negative control sera readings, for the confidence level of 99.5%. The sensitivity and specificity of the ELISA test were 95% and 91%, respectively. The ELISA test showed a significant concordance index (K=0.84) with the agar gel immunodiffusion test. The reliability of the ELISA for the detection of infected animals was established by a double blind study testing 280 sera provided by serum banks from different diagnostic and research institutions and analyzed by ROC Curve.

Efficacy of autologous stem cell-based therapy for osteonecrosis of the femoral head in sickle cell disease: a five-year follow-up study.

INTRODUCTION: Stem cell therapy with bone marrow-derived mononuclear cells (BMMCs) is an option for improving joint function in osteonecrosis of the femoral head (ONFH). Bone marrow-derived mesenchymal stromal cell (MSC) numbers and their osteogenic differentiation are decreased in patients with ONFH. However, whether this decrease also extends to the early stages of ONFH in sickle cell disease (SCD) is still unclear. METHODS: We conducted a phase I/II, non-controlled study to determine efficacy and safety of BMMC implantation using a minimally invasive technique in SCD patients with ONFH. Eighty-nine patients were recruited and followed up for 60 months after surgery. Clinical and radiographic findings were assessed, and data were completed by in vitro analysis. RESULTS: At the final follow-up (60 months) there was a significant improvement in clinical joint symptoms and pain relief as measured by the Harris Hip Score (P = 0.0005). In addition, after the BMMC implantation procedure, radiographic assessment showed disease stabilization and only 3.7 % of the treated patients did not achieve a satisfactory clinical result. The amount of fibroblast colony-forming units was 28.2 ± 13.9 per 1 million BMMCs after concentration. Flow cytometry analysis showed a significantly higher number of hematopoietic stem/endothelial progenitor cell markers in concentrated BMMCs when compared with bone marrow aspirate, indicating an enrichment of these cell types. Isolated MSCs from SCD patients with pre-collapse ONFH maintained the replicative capacity without significant loss of their specific biomolecular characteristics, multi-differentiation potential, and osteogenic differentiation activities. Cytokines and growth factors (interleukin-8, transforming growth factor-beta, stromal cell-derived factor-1alpha and vascular endothelial growth factor) that mediate endogenous bone regeneration were also produced by expanded MSCs from SCD patients. CONCLUSION: The autologous BMMC implantation with a minimally invasive technique resulted in significant pain relief and halted the progression of early stages of ONFH in SCD patients. MSCs from SCD patients display biological properties that may add to the efficiency of surgical treatment in ONFH. In summary, our results indicate that infusion of BMMCs enriched with stem/progenitor cells is a safe and effective treatment for the early stages of ONFH in SCD patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT02448121; registered 15 May 2015.

Whole-blood cultures from patients with chronic periodontitis respond differently to Porphyromonas gingivalis but not Escherichia coli lipopolysaccharide.

BACKGROUND: Porphyromonas gingivalis lipid A heterogeneity modulates cytokine expression in human cells. This study investigates the effects of two lipid A isoforms of P. gingivalis, lipopolysaccharide (LPS)1435/1449 and LPS1690, on the secretion of proinflammatory and regulatory cytokines in total blood cultures from patients with and without chronic periodontitis (CP). METHODS: A cross-sectional study was conducted in 38 systemically healthy individuals divided in two groups: 1) the CP group (n = 19), in which patients were diagnosed with CP; and 2) the no periodontitis (NP) group (n = 19), which included control patients without CP. Blood samples were collected from all patients, and whole-blood cell cultures (WBCCs) were stimulated for 48 hours with P. gingivalis LPS1435/1449 and LPS1690 and Escherichia coli LPS. Unstimulated WBCCs served as negative controls. The secretion of interferon-γ (IFN-γ), interleukin-10 (IL-10), and transforming growth factor-ß (TGF-ß) was detected in WBCC supernatants by enzyme-linked immunosorbent assays. RESULTS: E. coli LPS significantly increased the expression of all cytokines in WBCCs from both the NP and CP groups when compared to non-stimulated cells (control treatment). P. gingivalis LPS preparations increased IFN-γ levels in the CP group but not in the NP group when compared with controls (P <0.05). P. gingivalis LPS preparations also increased IL-10 and TGF-ß levels in both CP and NP groups, but P. gingivalis LPS1690 showed a three-fold increase on IL-10 production in the NP group (P <0.05) when compared to P. gingivalis LPS1435/144. CONCLUSIONS: These data demonstrate that WBCC cell populations obtained from healthy individuals and patients with CP may differ in the cytokine response to P. gingivalis but not E. coli LPS. This is consistent with the notion that CP alters the systemic WBCC response and that this can be detected by the different P. gingivalis LPS structures.

Role of IFN-γ and LPS on neuron/glial co-cultures infected by Neospora caninum.

Neospora caninum causes cattle abortion and neurological symptoms in dogs. Although infection is usually asymptomatic, classical neurological symptoms of neosporosis may be associated with encephalitis. This parasite can grow in brain endothelial cells without markedly damages, but it can modulate the cellular environment to promote its survival in the brain. In previous studies, we described that IFN-γ decreased the parasite proliferation and down regulated nitric oxide (NO) production in astrocyte/microglia cultures. However, it remains unclear how glial cells respond to N. caninum in the presence of neurons. Therefore, we evaluated the effect of 300 IU/mL IFN-γ or 1.0 mg/mL of LPS on infected rat neuron/glial co-cultures. After 72 h of infection, LPS did not affect the mitochondrial dehydrogenase activity. However, IFN-γ decreased this parameter by 15.5 and 12.0% in uninfected and infected cells, respectively. The number of tachyzoites decreased 54.1 and 44.3% in cells stimulated with IFN-γ and LPS, respectively. Infection or LPS treatment did not change NO production. On the other hand, IFN-γ induced increased nitrite release in 55.7%, but the infection reverted this induction. IL-10 levels increased only in infected cultures (treated or not), meanwhile PGE2 release was improved in IFN-γ/infected or LPS/infected cells. Although IFN-γ significantly reduced the neurite length in uninfected cultures (42.64%; p < 0.001), this inflammatory cytokine reverted the impairment of neurite outgrowth induced by the infection (81.39%). The results suggest a neuroprotective potential response of glia to N. caninum infection under IFN-γ stimulus. This observation contributes to understand the immune mediated mechanisms of neosporosis in central nervous system (CNS).

Seroepidemiology of hepatitis B in individuals born between 1945-1985 on a Brazilian regional metropolis / Soroepidemiologia da hepatite B em indivíduos nascidos entre 1945-1985 em uma metrópole regional Brasileira

Background: hepatitis B prevalence can be influenced by social/cultural behavior and the Baby Boomer (BB) generation(1945-1964) may have been more susceptible to this infection. Objectives: We investigated the seroprevalence of markers for HBV infection and vaccination and its association with main risk factors. Methodology: a random sample of individuals aged 30-70 years old in a public clinical laboratory from a metropolitan area of Bahia/Brazil were tested for HBsAg/Total Anti-HBc/Anti-HBs/Anti-HBc-IgM and a socio-demographic questionnaire was applied. Results: of the650 participants, 349 were 51-70 yo (BB) and 301 were non-BB. The prevalences were HBsAg (2.3%), Total Anti-HBc (17.1%) and Anti-HBs (27.4%). Anti-HBcIgM (2.7%) was performed in 112 participants sera who had contact/infection with HBV. The laboratory profiles were characterized as susceptibility (68%), vaccine response (14.8%) and contact/infection with HBV (17.2%). BB participants were more susceptible and less vaccinated than non-BB. The higher frequency of contact/infection status was observed in the BB generation. Statistically significant differences were found for the contact/infection status in males(50,9%) illicit drug use (11,6%), syringe/needle sharing (7,1%), and blood transfusion (10,7%). Non-BB with contact/ infection profile reported more tattoo/piercing and BB reported higher use of glass syringes. Conclusion: the majority of the study population was susceptible to infection but participants older than 50 years showed both, a higher frequency of this profile and also a higher frequency of contact/infection status, thus suggesting the need for greater health care attention for this age group.

Introdução: a prevalência de hepatite B pode ser influenciada pelo comportamento sociocultural e a geração Baby Boomer (BB) (1945-1964) pode ter sido mais suscetível a esta infecção. Objetivos: Investigar a soroprevalência de marcadores para a infecção pelo VHB e resposta vacinal e associação com fatores de risco. Metodologia: soro de indivíduos de 30 a 70 anos randomicamente selecionados em um laboratório publico de análises clínicas na área metropolitana do Brasil foram testados para AgHBs/ Anti-HBc Total /Anti-HBs/Anti-HBc-IgM. Todos responderam questionário sociodemográfico contendo perguntas sobre fatores de risco para hepatite B. Resultados: dos 650 participantes, 349 eram BB (51-70 anos) e 301 eram não-BB (30-50 anos). As prevalências estimadas foram: HBsAg (2,3%), Anti-HBs (27,4%). Entre os Anti-HBc Total (17,1%) apenas 2,7% foram Anti-HBc IgM. Os perfis laboratoriais foram caracterizados como suscetibilidade (68%), resposta vacinal (14,8%) e contato com VHB (17,2%). Na distribuição por idade, os BB foram mais susceptíveis, menos vacinados e apresentaram maior frequência de contato/infecção que os não-BB. Diferenças estatisticamente significantes foram encontradas no status contato/infecção e as seguintes variáveis: sexo masculino, uso de drogas ilícitas, compartilhamento de seringas de vidro/agulhas e transfusão de sangue. Não-BB com status contato/infecção relataram ter mais tatuagem/piercing e BB relataram maior uso de seringas de vidro. Conclusão: a maioria da população estudada era suscetível ao VHB, mas os participantes com mais de 50 anos apresentaram tanto uma maior frequência desse status quanto do status contato/ infecção, sugerindo a necessidade de maior atenção à saúde para indivíduos desta faixa etária.

Frequency and factors associated with Toxoplasma gondii infection in pregnant women and their pets in Ilhéus, Bahia, Brazil

Abstract INTRODUCTION: Toxoplasmosis is an asymptomatic disease that can lead to systemic disease in the fetus of pregnant women with primary infection. This study aimed to determine the prevalence of toxoplasmosis, associated factors, and correlation between the serology of pregnant women and their pets, in the municipality of Ilhéus, Bahia, Brazil. METHODS: This cross-sectional study was conducted in 196 pregnant women and their cats or dogs (n=89). Semi-structured interviews were conducted and serum samples from the pregnant women were tested to detect IgM and IgG antibodies against Toxoplasma gondii, and avidity tests were performed for IgM-positive samples. The serum collected from pets were tested for IgG antibodies, and IgM antibodies in cats. A non-conditional logistic regression analysis was performed to identify infection-associated factors. RESULTS: IgG and IgM antibodies were detected in 67.9% (133/196) and 1.5% (3/196) samples, respectively, for women with an avidity of over 60%. Age ≥ 25 and the presence of cats in the vicinity were found to be associated with infection, while the level of education and previous orientation toward prevention of toxoplasmosis were protective factors in pregnant women. IgG antibodies were detected in 46.1% (41/89) of the animals, and cats were found to be negative for IgM. For the animals, age ≥ 1 year was a factor associated with infection. There was no correlation between serology of the pregnant women and the animals (p=0.15). CONCLUSIONS: An elevated prevalence of toxoplasmosis was detected in the region. Therefore, the adoption of preventive measures by public healthcare bodies is recommended.

O receptor de quimiocina CXCR3/CD183 na tuberculose / The chemokine receptor CXCR3/CD183 in tuberculosis

Introdução: o receptor CXCR3/CD183 juntamente com seu indutor IFNy e seus ligantes CXCL9, CXCL10 e CXCL11 têm sido descritos como de grande importância na resposta imune do perfil T helper 1 (Th1). Este grupo de quimiocinas é expresso no microambiente e permite a migração de células ao sítio da infecção para combater o patógeno. Objetivo: revisar o atual estado da arte sobre o papel do receptor CXCR3/CD183 na tuberculose. Metodologia: o presente estudo inclui a revisão narrativa de 12 artigos que foram selecionados a partir de 74 artigos encontrados nas bases de dados PubMed e Sciencedirect entre primeiro de agosto e 31 de outubro de 2014. Resultados: diferentes abordagens vêm sendo utilizadas para o estudo desse receptor. A utilização de modelos animais como camundongos, coelhos e macacos é a mais comum. Porém, ensaios in vitro com células humanas do sangue periférico e efusão pleural também já foram utilizados para representar, com maior fidelidade, a resposta ao Mycobacterium tuberculosis (Mtb) pelo sistema imune humano. Esses estudos resultaram em importantes achados sobre o papel do receptor CXCR3 na tuberculose (TB), principalmente quanto à expressão em linfócitos e neutrófilos, assim como o padrão de coexpressão de outros receptores. Conclusão: o CXCR3 é o receptor de uma importante citocina (IP-10) induzida pelo IFN-gama, produzida na resposta Th1, eficaz na resposta à tuberculose. Nesse trabalho, resssalta-se que foram encontrados poucos estudos sobre o tema e isso demonstra a necessidade de realização de novas pesquisas, a fim de melhor investigar o papel desse importante receptor na tuberculose.

Introduction: the CXCR3/CD183 receptor along with its IFNy inducer and its ligands: the chemokines named CXCL9, CXCL10 and CXCL11 are of great importance in the Th1 (T helper 1) immune response. This group of chemokine modulates the migration of cells to the site of infection to defend against the pathogen. Objective: to investigate the current state of the art on the role of the receptor CXCR3/CD183 in tuberculosis. Methodology: the present study includes the narrative review of 12 articles that were selected from 74 articles found in the PubMed and Sciencedirect databases between August 1 and October 31, 2014. Results: different approaches have been used for the study of this receptor. The use of animal models such as mice, rabbits and monkeys is more common. However, in vitro assays with human peripheral blood cells and pleural effusion were also used to represent more faithfully the response to Mycobacterium tuberculosis (Mtb) by the human immune system. These studies resulted in significant findings on the role of the CXCR3 receptor in tuberculosis (TB), especially for expression in lymphocytes and neutrophils, as well as the pattern of co-expression of other receptors. Conclusion: CXCR3 is the receptor for an important cytokine (IP-10) induced by IFN-gamma, produced in the Th1 response, effective in responding to tuberculosis. In this work, it is emphasized that cheeses found few studies on the subject and demonstration, the need for conducting research, in order to better investigate the role of this important receptor in tuberculosis.

Interferon-gamma release assay performance in northeastern Brazil: influence of the IFNG+874 A>T polymorphism

ABSTRACT Introduction Latent tuberculosis infection diagnosis based on the release of interferon-gamma in cultures of peripheral blood cells stimulated with Mycobacterium tuberculosis antigens has replaced the tuberculin skin test in many countries with low tuberculosis prevalence. The IFN-γ production can be influenced by genetic polymorphisms, of which the IFNG + 874 (rs62559044) locus is the most studied. We investigated the possible influence of the IFNG + 874 A/T polymorphism on interferon-gamma test performance. Methods Patients diagnosed with pulmonary tuberculosis (75), volunteers with positive tuberculin skin test (70) and healthy volunteers with negative tuberculin skin test and no history of contact with tuberculosis (57) were evaluated regarding the IFNG + 874 genotype and the IFN-γ levels in whole blood cultures performed using an interferon-gamma commercial kit (QuantiFERON-TB® Gold In-Tube). Results IFN-γ production was not influenced by the IFNG + 874 genotype, regardless of antigen or mitogen-based stimulation, which suggests that other genes may influence IFN-γ production in response to mycobacteria. The IFNG + 874 polymorphism was found to exert no influence over QFT-IT test sensitivity in our study. Conclusions The IFNG + 874 polymorphism was not shown to influence QuantiFERON-TB® Gold In-Tube test performance in an admixed population from northeastern Brazil.

Rapid molecular test for tuberculosis: impact of its routine use at a referral hospital / Teste rápido molecular para tuberculose: avaliação do impacto de seu uso na rotina em um hospital de referência

ABSTRACT Objective: To evaluate the impact of the use of the molecular test for Mycobacterium tuberculosis and its resistance to rifampin (Xpert MTB/RIF), under routine conditions, at a referral hospital in the Brazilian state of Bahia. Methods: This was a descriptive study using the database of the Mycobacteriology Laboratory of the Octávio Mangabeira Specialized Hospital, in the city of Salvador, and georeferencing software. We evaluated 3,877 sputum samples collected from symptomatic respiratory patients, under routine conditions, between June of 2014 and March of 2015. All of the samples were submitted to sputum smear microscopy and the Xpert MTB/RIF test. Patients were stratified by gender, age, and geolocation. Results: Among the 3,877 sputum samples evaluated, the Xpert MTB/RIF test detected M. tuberculosis in 678 (17.5%), of which 60 (8.8%) showed resistance to rifampin. The Xpert MTB/RIF test detected M. tuberculosis in 254 patients who tested negative for sputum smear microscopy, thus increasing the diagnostic power by 59.9%. Conclusions: The use of the Xpert MTB/RIF test, under routine conditions, significantly increased the detection of cases of tuberculosis among sputum smear-negative patients.

RESUMO Objetivo: Avaliar o impacto do teste rápido molecular automatizado Xpert MTB/RIF, utilizado para a detecção de Mycobacterium tuberculosis e sua resistência à rifampicina, em condições de rotina, em um hospital de referência no estado da Bahia. Métodos: Estudo descritivo retrospectivo utilizando o banco de dados do Laboratório de Micobacteriologia do Hospital Especializado Octávio Mangabeira, localizado na cidade de Salvador, e um programa de georreferenciamento. Entre junho de 2014 e março de 2015, foram incluídas no estudo 3.877 amostras de escarro coletadas de pacientes sintomáticos respiratórios em condições de rotina. Todas as amostras coletadas foram submetidas tanto à baciloscopia quanto a Xpert MTB/RIF. Os pacientes foram estratificados por sexo, idade e georreferenciamento. Resultados: Das 3.877 amostras de escarro analisadas, Xpert MTB/RIF detectou a presença de M. tuberculosis em 678 pacientes (17,5%). Desses, 60 (8,8%) apresentaram resistência à rifampicina. O Xpert MTB/RIF detectou 254 pacientes com baciloscopia negativa, representando um acréscimo diagnóstico de 59,9%. Conclusões: A implantação do Xpert MTB/RIF, sob condições de rotina, teve um impacto significativo no aumento da detecção de casos de tuberculose em pacientes com baciloscopia negativa.

Hepatite B na Bahia, Brasil segundo sistema de informação de agravos de notificação, 2013 / Hepatitis B in Bahia, Brazil according to the notifiable diseases surveillance system database, 2013

Objetivo: estudar os aspectos sócio-demográficos e epidemiológicos da hepatite B no estado da Bahia e avaliar a metodologia da notificação. Metodologia: em estudo descritivo foram avaliados os registros dados de pacientes do estado da Bahia notificados com hepatite B no Sistema de Informação de Agravos de Notificação. A amostra foi de 371 notificações, de janeiro a agosto de 2013. Das 52 variáveis que constituem a Ficha de Investigação (SINAN) foram selecionadas 10 variáveis de importância epidemiológica para hepatite B (HB), por relevância neste estudo, para cálculo das frequências absolutas e relativas. Resultados: em relação aos aspectos sócio-demográficos 53,4% foram do sexo masculino e a média de idade foi de 38 anos, mínima de 4 e máxima de 78 anos. As maiores fontes de transmissão foram a sexual 62,2% pessoa/pessoa 6,4% e transfusão de hemoderivados 4,8%. A variável "ignorados" correspondeu a 47,3% das notificações. Sobre a escolaridade dos infectados 22,9% eram do Ensino Médio Completo e 22,5% Fundamental Incompleto. Salvador foi o município que mais notificou casos do vírus da hepatite B (HBV) com 91, seguido por Jequié 35 e Camaçari 24. Não fizeram uso da vacina contra HBV 76,0%. Na classificação etiológica 97,3% foi de monoinfecção pelo HBV e 2,7% co-infecção com HCV. Na classificação clínica 86,9% apresentaram HB crônica e 10,4% HB aguda. Conclusão: encontrou-se pouca associação entre escolaridade e HB na população. A variável de maior fonte de transmissão registrada foi à sexual. O sexo masculino apresentou maior frequência para o HBV. Observou-se que na maioria dos notificados havia itens importantes não preenchidos.

Objective: to study the sociodemographic and epidemiological aspects of hepatitis b in the state of bahia, brazil and to evaluate the methodology involved in the notification procedure. Methodology: this descriptive study evaluated data referring to 371 patients from the state of Bahia registered as cases of hepatitis B in the national notifiable diseases surveillance system (SINAN) database between January and August 2013. Of the 52 variables included in the SINAN investigation form, 10 variables of epidemiological importance were selected and described as absolute and relative frequencies. Results: regarding the sociodemographic aspects, 53.4% of cases were male and the mean age was 38 years (range 4-78 years). Transmission was mainly sexual (62.2%),person-to ­ person (6.4%) or by transfusion of blood products (4.8%). In 47.3%, the mode of transmission was unknown. Regarding education, 22.9% of cases had completed high school, while 22.5% had failed to complete elementary school. With 91 cases, Salvador was the city with most notifications, followed by Jequié (35) and Camaçari (24).Overall, 76.0% had not been vaccinated against the hepatitis B virus (HBV). In the etiological classification, 97.3% of cases consisted of HBV mono-infection, while 2.7% were co-infected with the hepatitis C virus. Clinically, the disease was chronic in 86.9% of cases and acute in 10.4%. Conclusion: education level and hepatitis B were found to be associated in this population. The most common mode of transmission was sexual, with most cases occurring in males. In the majority of cases, important items on the notification form had not been completed.