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1.
Am J Trop Med Hyg ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32043459

RESUMO

In some areas of Argentina endemic for human T-lymphotropic virus type 1 (HTLV-1), tropical spastic paraparesis is frequent in subjects who lack antibodies against the virus; however, the relevance of this seronegative status in the country has not been investigated. In neighboring countries, HTLV-1-seronegative status has been described in patients with different diseases; however, data regarding features of seronegative HTLV-1 carriers are scarce. We investigated the seronegative status in 124 relatives of 28 HTLV-1-infected subjects from an endemic area in Northwest Argentina. Blood samples and clinical/epidemiological data were collected. Human T-lymphotropic virus type 1 infection was diagnosed by serology and LTR, env and tax gene detection. IgG anti-Tax HTLV-1 antibody, tax gene sequence, and DNA proviral load were also evaluated. Seventy-five percent of the 124 relatives were negative for HTLV-1/2 antibodies; 35.5% were also negative by molecular assays and 64.5% were negative for HTLV-1 LTR and env sequences, but positive for two sequences of HTLV-1 tax gene. Also, 35.7% of these subjects had IgG anti-Tax antibodies. The seronegative HTLV-1 status was significantly associated with male gender, youth, and sensory symptoms/autonomic nervous system dysfunction. High rates of seronegative symptomatic and asymptomatic HTLV-1 carriers in Argentina are described. The evidence highlights that HTLV-1 prevalence may be underestimated worldwide. Larger cohort studies are required to assess disease outcome in these seronegative subjects. Also, the findings emphasize the limitations of ongoing screening assays for diagnosis and blood safety. Therefore, algorithms for HTLV-1 diagnosis should include not only serological but also molecular assays.

2.
Vaccine ; 38(12): 2678-2682, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32061386

RESUMO

Universal vaccination is the most effective strategy to control hepatitis B virus (HBV) infection. In Argentina, vaccination against HBV was incorporated in year 2000 for newborns and in 2003 for 11 years old children. However, there is a paucity of data about protection levels against HBV infection. The aim of this work was to determine the prevalence of seroprotective anti-HBs antibodies (aHBs) in Argentina. Serum samples negative for HBsAg and anti-HBc from 132 children born after year 2000 and 762 blood donors, older than 18 years, from five centers across the country, were analyzed for aHBs. Titers ≥10 mIU/mL were observed in 74/132 children (56.1%) and 336/762 (44.1%) in blood donors. The median age for blood donors was 33.9 (23-43); from them, 210 (27.6%) were born after 1992 and, therefore, were catch-up by vaccine implementation at 11 years old age. Donors born in 1992 or before showed a significantly lower frequency of protection (32.2%) compared to donors born after 1992 (75.2%), p < 0.0001. In addition, significant differences were observed in the status of seroprotection between different participating centers (p = 0.024). Implementation of HBV vaccine in 2000 and 2003 implied an overall increase of the aHBs seroprotective rates, with a particularly adequate response in children vaccinated at 11 years old age. The observed results suggest that population born in 1992 or before is currently the most susceptible. Consequently, it would be advisable to become aware of the risk of transmission in this age group and to stress this population vaccination campaigns.

3.
J Matern Fetal Neonatal Med ; : 1-6, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31973628

RESUMO

Introduction: Even though Fetal and Neonatal Alloimmune Thrombocytopenia (FNAIT) has been recognized as the main cause of primary hemorrhagic morbidity and mortality in fetuses and newborns, screening programs to detect pregnancies at risk have not yet been implemented in any country. Moreover, in spite of increased concerns about maternal, fetal and neonatal health care in general, this potentially lethal disease is still underdiagnosed. The aim of this report is to highlight the importance of considering FNAIT in fetal and perinatal health-care settings and show the usefulness of molecular tools in early diagnosis of this clinical entity.Methods: DNA was extracted from whole blood from parents and newborns; genotyping was performed by in house PCR using sequence-specific primers for typing Human Platelet Antigens (HPA)-1 to -6, -9, and -15, and with commercial HPA-TYPE (BAG HealthCare, Lich, Germany). Anti-HPA antibodies in the maternal serum were detected by the Monoclonal Antibody Solid Phase Platelet antibody Test (MASPAT). Chloroquine-treated platelets were used for the discrimination of platelet-specific antibodies from anti-HLA antibodies.Results: Patients 1 and 2 had severe thrombocytopenia due to incompatibility in HPA-1 and HPA-15, respectively. The third case was a thrombocytopenic neonate with severe bleeding complications other than ICH and in whom differential diagnosis between FNAIT and Von Willebrand congenital disease was necessary; incompatibility in HPA-15 was also demonstrated. Case 4 represents a missed diagnostic opportunity.Conclusion: This is the first report of FNAIT cases confirmed by molecular evidence and anti-HPA antibodies detection in Argentina. This report reinforces the relevance of early diagnosis of this clinical entity. Since the delay in FNAIT diagnosis could lead to severe consequences in the fetus and neonates, strategies to approach maternal, fetal, and perinatal health, as well as prevention policies aimed to reduce fetal and neonatal morbidity and mortality should focus on implementing programs to identify high-risk pregnancies and thus reduce thrombocytopenia-related complications in fetuses and newborns.

4.
Transfus Med Hemother ; 45(6): 423-428, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30800032

RESUMO

Introduction: Since anti-D immunoprophylaxis given to D-negative pregnant women is a blood product, blood donations have an impact on the availability of prophylactic doses. The Pan American Health Organization reported, in June 2017, that less than half of blood donors are volunteers in Latin America and the Caribbean. In these countries, guidelines for use of anti-D prophylaxis are still controversial. The aim of this study was to demonstrate the convenience of a simple and cost-effectivene non-invasive prenatal diagnostic assay for anti-D prophylaxis optimization in multiethnic populations. Methods: Cell-free fetal DNA from plasma samples of D-negative pregnant women were analyzed by real-time PCR for simultaneous amplification of sequences of exons 5 and 10 of the RHD gene. Fetal RHD genotype was determined in 111 pregnant women. Neonates' phenotype was determined 72 h after birth. Results: Genotyping predicted fetal phenotype with 100% accuracy. Prenatal diagnosis showed 78% RHD-positive and 22% RHD-negative neonates. Conclusion: We demonstrated that, beyond the large genetic variation of the Rh system and the numerous D variants present in multiethnic groups, non-invasive fetal RHD genotyping using two sequences of the gene can be enough for clinical application in an admixed population. This robust technique of simple implementation allows to determine fetal RHD in maternal blood with high sensitivity, specificity, and accuracy. The introduction of fetal RhD genotyping as part of an antenatal screening program constitutes a reliable manner to optimize anti-D prophylaxis; however, it has not been implemented so far in most American countries.

5.
Rev Chilena Infectol ; 34(2): 108-115, 2017 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-28632823

RESUMO

INTRODUCTION: Whooping cough is a re-emerging infection in the world and Latin America. OBJECTIVE: It was considered relevant to investigate the clinical and epidemiological profile of Bordetella spp. and Bordetella pertussis infection in Córdoba province, Argentina; evaluating, at the same time, the co-infection with virus producing respiratory infections that may be confused with whooping cough. MATERIAL AND METHODS: All whooping cough suspected cases were studied by Polimerase Chain Reaction, amplifying the repeated insertion sequence (IS) 481 and the promoter gene encoding pertussis toxin, between 2011 and 2013. The data were obtained from the clinical and epidemiological records. RESULTS: From 2,588 whooping cough suspected cases, 11.59% was infected by Bordetella spp. and 9.16% was confirmed as Bordetella pertussis infection. The rate of infection was 7.22 and 1.84 per 100,000 for 2011 and 2012, respectively. The infection presented a seasonal tendency and it was mainly found on the group of children between 13 and 24 months old. The co-infection with virus producing respiratory infections, were uncommon. Paroxysmal cough, cyanosis and/or vomiting were predictors of the infection for Bordetella pertussis. DISCUSSION AND CONCLUSIONS: To deal with the re-emergence of whooping cough is important the knowledge of the regional epidemiological situation. This paper shows the situation of these infections in the regional clinical and epidemiological context, and makes the information available for health decision-making.


Assuntos
Bordetella/genética , Doenças Transmissíveis Emergentes/epidemiologia , Coqueluche/diagnóstico , Argentina/epidemiologia , Bordetella/classificação , Bordetella pertussis/genética , Criança , Pré-Escolar , Doenças Transmissíveis Emergentes/diagnóstico , Doenças Transmissíveis Emergentes/virologia , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase , Coqueluche/epidemiologia , Coqueluche/virologia
6.
PLoS One ; 12(4): e0174920, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28384180

RESUMO

BACKGROUND: Molecular and epidemiological studies of transmission routes and risk factors for infection by HTLV-1 are extremely important in order to implement control measures, especially because of the high prevalence of HTLV-1 in several regions of the world. San Salvador de Jujuy, Northwest Argentina, is a highly endemic area for HTLV-1 and foci of tropical spastic paraparesis/HTLV-1-associated myelopathy. OBJECTIVE: To gain further insight into the role of intrafamilial transmission of HTLV-1 in a highly endemic region in Argentina. METHOD: Cross-sectional study in Northwest Argentina. Epidemiological data and blood samples were collected from 28 HTLV-1 infected subjects (index cases) and 92 close relatives/cohabitants. HTLV-1 infection was diagnosed by detection of antibodies and proviral DNA. The LTR region was sequenced and analyzed for genetic distances (VESPA software), in addition to determination and identification of polymorphisms to define HTLV-1 family signatures. RESULTS: Fifty seven of the 120 subjects enrolled had antibodies against HTLV-1 and were typified as HTLV-1 by PCR. The prevalence rate of HTLV-1 infection in family members of infected index cases was 31.52% (29/92). The infection was significantly associated with gender, age and prolonged lactation. Identity of LTR sequences and presence of polymorphisms revealed high prevalence of mother-to-child and interspousal transmission of HTLV-1 among these families. CONCLUSION: There is an ongoing and silent transmission of HTLV-1 through vertical and sexual routes within family clusters in Northwest Argentina. This evidence highlights that HTLV-1 infection should be considered as a matter of public health in Argentina, in order to introduce preventive measures as prenatal screening and breastfeeding control.


Assuntos
Paraparesia Espástica Tropical/epidemiologia , Argentina/epidemiologia , Doenças Endêmicas , Feminino , Predisposição Genética para Doença , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Transmissão Vertical de Doença Infecciosa , Masculino , Paraparesia Espástica Tropical/transmissão , Linhagem , Gravidez , Doenças Virais Sexualmente Transmissíveis/epidemiologia , Doenças Virais Sexualmente Transmissíveis/transmissão
7.
Rev. chil. infectol ; 34(2): 108-115, abr. 2017. graf, tab
Artigo em Espanhol | LILACS-Express | ID: biblio-844453

RESUMO

Introduction: Whooping cough is a re-emerging infection in the world and Latin America. Objective: It was considered relevant to investigate the clinical and epidemiological profile of Bordetella spp. and Bordetella pertussis infection in Córdoba province, Argentina; evaluating, at the same time, the co-infection with virus producing respiratory infections that may be confused with whooping cough. Material and Methods: All whooping cough suspected cases were studied by Polimerase Chain Reaction, amplifying the repeated insertion sequence (IS) 481 and the promoter gene encoding pertussis toxin, between 2011 and 2013. The data were obtained from the clinical and epidemiological records. Results: From 2,588 whooping cough suspected cases, 11.59% was infected by Bordetella spp. and 9.16% was confirmed as Bordetella pertussis infection. The rate of infection was 7.22 and 1.84 per 100,000 for 2011 and 2012, respectively. The infection presented a seasonal tendency and it was mainly found on the group of children between 13 and 24 months old. The co-infection with virus producing respiratory infections, were uncommon. Paroxysmal cough, cyanosis and/or vomiting were predictors of the infection for Bordetella pertussis. Discussion and Conclusions: To deal with the re-emergence of whooping cough is important the knowledge of the regional epidemiological situation. This paper shows the situation of these infections in the regional clinical and epidemiological context, and makes the information available for health decision-making.


Introducción: Coqueluche es una enfermedad reemergente en el mundo y en Latinoamérica. Objetivo: Resultó de interés caracterizar el perfil clínico-epidemiológico de la infección por Bordetella spp. y Bordetella pertussis en Córdoba, Argentina; evaluando además, la frecuencia de infecciones de etiología viral que, por cursar con un síndrome coqueluchoide (SC), pueden ser confundidas con cuadros de coqueluche. Material y Métodos: Los casos sospechosos de coqueluche, se estudiaron por reacción de polimerasa en cadena; amplificando la secuencia repetida de inserción (IS) 481 y la región promotora del gen de la toxina pertussis; entre 2011 y 2013. Los datos de los pacientes se obtuvieron de las fichas clínicoepidemiológicas. Resultados: De 2.588 pacientes, 11,59% presentó una infección por Bordetella spp. y en 9,16% se confirmó una infección por Bordetella pertussis. La tasa de infección fue 7,22 y 1,84 por 100.000 habitantes en 2011 y 2012, respectivamente. La infección presentó una tendencia estacional y se concentró principalmente en niños entre 13 y 24 meses. La tos paroxística, cianosis y/o vómitos fueron predictores de la infección por B. pertussis. La coinfección con virus productores de infecciones respiratorias fue poco frecuente. Discusión y Conclusiones: Es fundamental el conocimiento de la situación epidemiológica regional. Este trabajo presenta la situación de Córdoba y pone a disposición de la comunidad sanitaria la información para la toma de decisiones en el contexto clínico-epidemiológico regional.

8.
Transfusion ; 57(3pt2): 816-822, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27917495

RESUMO

BACKGROUND: Results from 10-year experience using nucleic acid test (NAT) screening in a blood bank of Córdoba are presented, showing the first data on prevalence of recent hepatitis B virus (HBV) infections and occult HBV infections (OBIs) in Argentina. STUDY DESIGN AND METHODS: Molecular screening was performed by COBAS AmpliScreen human immunodeficiency virus Type 1 (HIV-1) test Version 1.5 and COBAS AmpliScreen hepatitis C virus (HCV) test Version 2.0 and COBAS TaqScreen MPX and MPX Version 2.0 test (Roche Molecular Systems). To characterize OBI, additional molecular and serologic assays were performed. RESULTS: As results of NAT, 0.075% of the donors (155/205,388) tested positive for HIV, 0.05% (106/205,388) for HCV, and 0.045% (76/168,215) for HBV. Donors who tested positive for HIV or HCV by NAT were also positive by serology. There was one of 33,643 donors recently infected with HBV. At time of donation, six of 76 (7.9%) donors with confirmed HBV infection presented virologic and serologic profiles consistent with OBI. By additional studies three were OBI, two were window period infections, and one remained unclassified. CONCLUSION: NAT contributed significantly to the reduction of the potential risk of HBV transmission with a frequency of one in 56,072, detecting three in 168,215 donors without serologic evidence of infection. NAT also detected three in 168,215 OBIs. The finding of high frequency of recent infections (1/33,643), unexpected for this country, highlights the need of promoting unified effective regulations that enforce the use of NAT in all blood banks in Argentina and points out the importance of assessing the risk of HBV transmission in blood banks of other countries considered to be low-endemic.


Assuntos
Bancos de Sangue/métodos , Transfusão de Sangue , Vírus da Hepatite B , Hepatite B/sangue , Hepatite B/prevenção & controle , Técnicas de Amplificação de Ácido Nucleico/métodos , Argentina , Feminino , Seguimentos , Soropositividade para HIV/sangue , Soropositividade para HIV/transmissão , HIV-1 , Hepacivirus , Hepatite B/transmissão , Humanos , Masculino
9.
Arch Virol ; 161(10): 2813-7, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27383207

RESUMO

This study describes the prevalence of HBV infection based on detection of HBsAg and HBV-DNA by NAT in 70,102 blood donors in Argentina (Córdoba province) and shows the viral genotype distribution and frequency of occult HBV infection (OBI) in this population. Forty-two donors were confirmed positive for HBV infection (0.06 %), and four had OBI. Genotype F was the most prevalent (71.4 %), followed by A (14.3 %), C (7.1 %) and D (7.1 %). This is the first report of the prevalence of confirmed HBV infection and the high frequency of occult HBV infection in a blood bank in Argentina.


Assuntos
Doadores de Sangue , DNA Viral/sangue , Genótipo , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/classificação , Vírus da Hepatite B/isolamento & purificação , Hepatite B/epidemiologia , Adulto , Argentina/epidemiologia , Feminino , Vírus da Hepatite B/genética , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
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