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1.
Toxins (Basel) ; 9(11)2017 10 25.
Article in English | MEDLINE | ID: mdl-29068360

ABSTRACT

Shiga toxin (Stx), produced by Escherichia coli, is the main pathogenic factor of diarrhea-associated hemolytic uremic syndrome (HUS), which is characterized by the obstruction of renal microvasculature by platelet-fibrin thrombi. It is well known that the oxidative imbalance generated by Stx induces platelet activation, contributing to thrombus formation. Moreover, activated platelets release soluble CD40 ligand (sCD40L), which in turn contributes to oxidative imbalance, triggering the release of reactive oxidative species (ROS) on various cellular types. The aim of this work was to determine if the interaction between the oxidative response and platelet-derived sCD40L, as consequence of Stx-induced endothelium damage, participates in the pathogenic mechanism during HUS. Activated human glomerular endothelial cells (HGEC) by Stx2 induced platelets to adhere to them. Although platelet adhesion did not contribute to endothelial damage, high levels of sCD40L were released to the medium. The release of sCD40L by activated platelets was inhibited by antioxidant treatment. Furthermore, we found increased levels of sCD40L in plasma from HUS patients, which were also able to trigger the respiratory burst in monocytes in a sCD40L-dependent manner. Thus, we concluded that platelet-derived sCD40L and the oxidative response are reciprocally stimulated during Stx2-associated HUS. This process may contribute to the evolution of glomerular occlusion and the microangiopathic lesions.


Subject(s)
CD40 Ligand/blood , Endothelial Cells/drug effects , Hemolytic-Uremic Syndrome/blood , Shiga Toxin/toxicity , Cells, Cultured , Child , Child, Preschool , Endothelial Cells/pathology , Female , Hemolytic-Uremic Syndrome/chemically induced , Humans , Infant , Kidney/metabolism , Kidney/pathology , Male , Microvessels , Monocytes/metabolism , Oxidative Stress , Platelet Activation/drug effects , Reactive Oxygen Species/metabolism
2.
Medicina (B Aires) ; 71(4): 383-9, 2011.
Article in Spanish | MEDLINE | ID: mdl-21893458

ABSTRACT

The typical form of hemolytic uremic syndrome (HUS) is the major complication of Shiga toxin-producing Escherichia coli (STEC) infections. HUS is a critical health problem in Argentina since it is the main cause of acute renal failure in children and the second cause of chronic renal failure, giving account for 20% of renal transplants in children and adolescents in our country. In spite of the extensive research in the field, the mainstay of treatment for patients with HUS is supportive therapy, and there are no specific therapies preventing or ameliorating the disease course. In this review, we present the current knowledge about pathogenic mechanisms and discuss traditional and innovative therapeutic approaches, with special focus in national status and contributions made by Argentinean groups.


Subject(s)
Hemolytic-Uremic Syndrome , Shiga-Toxigenic Escherichia coli , Argentina/epidemiology , Hemolytic-Uremic Syndrome/epidemiology , Hemolytic-Uremic Syndrome/microbiology , Hemolytic-Uremic Syndrome/therapy , Humans , Shiga-Toxigenic Escherichia coli/pathogenicity
3.
Medicina (B.Aires) ; 71(4): 383-389, July-Aug. 2011. ilus
Article in Spanish | LILACS | ID: lil-633884

ABSTRACT

La forma típica o post-diarreica del síndrome urémico hemolítico (SUH) es la complicación más grave de las infecciones por cepas de Escherichia coli productoras de toxina Shiga (STEC). En la Argentina el SUH es un problema crítico de salud pública, ya que representa la principal causa de falla renal aguda en la infancia, la segunda causa de falla renal crónica, y aporta el 20% de los casos de transplante renal durante la infancia y la adolescencia. A pesar de los avances en el conocimiento de su patogénesis, el único tratamiento actual de los pacientes con SUH es de sostén, y no existen terapias específicas ni preventivas. En la presente revisión expondremos los conocimientos básicos de los mecanismos patogénicos y discutiremos los enfoques terapéuticos tradicionales e innovadores, con especial foco en la situación nacional y los aportes hechos por grupos de la Argentina.


The typical form of hemolytic uremic syndrome (HUS) is the major complication of Shiga toxin-producing Escherichia coli (STEC) infections. HUS is a critical health problem in Argentina since it is the main cause of acute renal failure in children and the second cause of chronic renal failure, giving account for 20% of renal transplants in children and adolescents in our country. In spite of the extensive research in the field, the mainstay of treatment for patients with HUS is supportive therapy, and there are no specific therapies preventing or ameliorating the disease course. In this review, we present the current knowledge about pathogenic mechanisms and discuss traditional and innovative therapeutic approaches, with special focus in national status and contributions made by Argentinean groups.


Subject(s)
Humans , Hemolytic-Uremic Syndrome , Shiga-Toxigenic Escherichia coli , Argentina/epidemiology , Hemolytic-Uremic Syndrome/epidemiology , Hemolytic-Uremic Syndrome/microbiology , Hemolytic-Uremic Syndrome/therapy , Shiga-Toxigenic Escherichia coli/pathogenicity
4.
Expert Rev Anti Infect Ther ; 7(6): 697-707, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19681698

ABSTRACT

The typical form of hemolytic uremic syndrome (HUS) is the major complication of Shiga toxin-producing Escherichia coli infections. HUS is a critical health problem in Argentina since it is the main cause of acute renal failure in children and the second cause of chronic renal failure, accounting for 20% of renal transplants in children and adolescents in Argentina. Despite extensive research in the field, the mainstay of treatment for patients with HUS is supportive therapy, and there are no specific therapies preventing or ameliorating the disease course. In this review, we present the current knowledge about pathogenic mechanisms and discuss traditional and innovative therapeutic approaches, with special focus in Argentinean contribution. The hope that a better understanding of transmission dynamics and pathogenesis of this disease will produce better therapies to prevent the acute mortality and the long-term morbidity of HUS is the driving force for intensified research.


Subject(s)
Escherichia coli O157/pathogenicity , Hemolytic-Uremic Syndrome/physiopathology , Hemolytic-Uremic Syndrome/therapy , Shiga Toxin/toxicity , Adolescent , Anticoagulants/therapeutic use , Argentina/epidemiology , Child , Escherichia coli Infections/epidemiology , Escherichia coli Infections/microbiology , Escherichia coli Infections/physiopathology , Escherichia coli Infections/therapy , Fluid Therapy , Hemolytic-Uremic Syndrome/epidemiology , Hemolytic-Uremic Syndrome/microbiology , Humans , Randomized Controlled Trials as Topic , Renal Dialysis , Renal Insufficiency/etiology , Shiga Toxin/metabolism , Treatment Outcome
5.
Arch Argent Pediatr ; 106(2): 102-9, 2008 Apr.
Article in Spanish | MEDLINE | ID: mdl-18661034

ABSTRACT

OBJECTIVE: To examine the interrelationships of body composition variables derived from simple anthropometry, bioelectrical impedance (BIA) and dualenergy X-ray absorptiometry (DXA). POPULATION, MATERIAL AND METHODS: A total of 230 healthy preschool children (118 males and 112 females) age 4-6 years, attending a day care center, were examined to determine body mass index (BMI) and waist circumference (WC). Percentage of body fat content (%BF) was predicted by BIA (Maltron BF- 900) and DXA (Lunar DPX-L, pediatric software). RESULTS: BMI and WC did not show significant differences among sex, while %BF by BIA or DXA did. BIA measures were lower than DXA s (p <0.0001). Correlation between BIA vs. anthropometric methods and WC vs. DXA were moderate (Pearson r= 0.43 to 0.53), whereas the other correlations were strong (r= 0.71 to 0.83). However Bland Altman comparison showed wide limits of agreement between BIA and DXA; BIA significantly underestimated %BF as determined by DXA (p <0.0001). CONCLUSION: The methods used to estimate body composition in healthy preschool children highly correlated. However, the Bland Altman procedure suggests that BIA and DXA should not be used interchangeably.


Subject(s)
Absorptiometry, Photon , Anthropometry , Body Composition , Electric Impedance , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Male
6.
Arch. argent. pediatr ; 106(2): 102-109, abr.2008. graf, tab
Article in Spanish | BINACIS | ID: bin-122268

ABSTRACT

Objetivo. Comparar la composición corporal estimadapor dos métodos antropométricos simples ypor impedanciometría (BIA, por sus siglas en inglés)y absorciometría de doble haz de rayos X(DXA, por sus siglas en inglés) y estudiar las correlacionesexistentes entre ellos, en una poblaciónpreescolar de Argentina.Población, material y métodos. Se estudió transversalmenteuna población clínicamente sana, deedad comprendida entre 4 y 6 años, de 230 niños(118 varones y 112 niñas), que concurrían a JardinesIntegrales de La Matanza, Argentina. Se determinóel índice de masa corporal (IMC), la circunferenciade cintura (Cci) y el contenido de grasa corporal,expresado como porcentaje, por BIA (Maltron BF-900) y por DXA (densitómetro Lunar DPX-L, softwarepediátrico).Resultados. En IMC y Cci no se observaron diferenciasestadísticamente significativas entre ambossexos, pero sí en el porcentaje de grasa corporal porBIA o DXA. La correlación entre BIA y ambos métodosantropométricos fue moderada (r de Pearson=0,43-0,53), al igual que entre DXA y Cci (r= 0,66),mientras que las demás correlaciones fueron fuertes(r= 0,71-0,83). Las medidas obtenidas por BIA yDXA no concordaron (prueba de Bland Altman); sinembargo, las diferencias se distribuyeron en formahomogénea a lo largo del eje horizontal e independientementede las medias. BIA reprodujo valoresmás bajos de porcentaje de grasa corporal que DXA(p <0,0001).Conclusiones. Existe buena correlación entre losmétodos antropométricos sencillos y la bioimpedanciay DXA. Sin embargo, los resultados no sonintercambiables, incluso entre BIA y DXA (AU)


Objective. To examine the interrelationships of body composition variables derived from simple anthropometry, bioelectrical impedance (BIA) and dualenergy X-ray absorptiometry (DXA). Population, material and methods. A total of 230 healthy preschool children (118 males and 112 females) age 4-6 years, attending a day care center, were examined to determine body mass index (BMI) and waist circumference (WC). Percentage of body fat content (%BF) was predicted by BIA (Maltron BF- 900) and DXA (Lunar DPX-L, pediatric software). Results. BMI and WC did not show significant differences among sex, while %BF by BIA or DXA did. BIA measures were lower than DXA´s (p <0.0001). Correlation between BIA vs. anthropometric methods and WC vs. DXA were moderate (Pearson r= 0.43 to 0.53), whereas the other correlations were strong (r= 0.71 to 0.83). However Bland Altman comparison showed wide limits of agreementbetween BIA and DXA; BIA significantly underestimated %BF as determined by DXA (p <0.0001). Conclusion. The methods used to estimate body composition in healthy preschool children highly correlated. However, the Bland Altman procedure suggests that BIA and DXA should not be used interchangeably.(AU)


Subject(s)
Child, Preschool , Child , Body Composition , Anthropometry , Absorptiometry, Photon , Weight by Height , Body Mass Index , Weight by Age , Observational Studies as Topic , Cross-Sectional Studies , Epidemiology, Descriptive , Comparative Study , Data Interpretation, Statistical
7.
Arch. argent. pediatr ; 106(2): 102-109, abr.2008. graf, tab
Article in Spanish | LILACS | ID: lil-482394

ABSTRACT

Objetivo. Comparar la composición corporal estimadapor dos métodos antropométricos simples ypor impedanciometría (BIA, por sus siglas en inglés)y absorciometría de doble haz de rayos X(DXA, por sus siglas en inglés) y estudiar las correlacionesexistentes entre ellos, en una poblaciónpreescolar de Argentina.Población, material y métodos. Se estudió transversalmenteuna población clínicamente sana, deedad comprendida entre 4 y 6 años, de 230 niños(118 varones y 112 niñas), que concurrían a JardinesIntegrales de La Matanza, Argentina. Se determinóel índice de masa corporal (IMC), la circunferenciade cintura (Cci) y el contenido de grasa corporal,expresado como porcentaje, por BIA (Maltron BF-900) y por DXA (densitómetro Lunar DPX-L, softwarepediátrico).Resultados. En IMC y Cci no se observaron diferenciasestadísticamente significativas entre ambossexos, pero sí en el porcentaje de grasa corporal porBIA o DXA. La correlación entre BIA y ambos métodosantropométricos fue moderada (r de Pearson=0,43-0,53), al igual que entre DXA y Cci (r= 0,66),mientras que las demás correlaciones fueron fuertes(r= 0,71-0,83). Las medidas obtenidas por BIA yDXA no concordaron (prueba de Bland Altman); sinembargo, las diferencias se distribuyeron en formahomogénea a lo largo del eje horizontal e independientementede las medias. BIA reprodujo valoresmás bajos de porcentaje de grasa corporal que DXA(p <0,0001).Conclusiones. Existe buena correlación entre losmétodos antropométricos sencillos y la bioimpedanciay DXA. Sin embargo, los resultados no sonintercambiables, incluso entre BIA y DXA


Objective. To examine the interrelationships of body composition variables derived from simple anthropometry, bioelectrical impedance (BIA) and dualenergy X-ray absorptiometry (DXA). Population, material and methods. A total of 230 healthy preschool children (118 males and 112 females) age 4-6 years, attending a day care center, were examined to determine body mass index (BMI) and waist circumference (WC). Percentage of body fat content (%BF) was predicted by BIA (Maltron BF- 900) and DXA (Lunar DPX-L, pediatric software). Results. BMI and WC did not show significant differences among sex, while %BF by BIA or DXA did. BIA measures were lower than DXA´s (p <0.0001). Correlation between BIA vs. anthropometric methods and WC vs. DXA were moderate (Pearson r= 0.43 to 0.53), whereas the other correlations were strong (r= 0.71 to 0.83). However Bland Altman comparison showed wide limits of agreementbetween BIA and DXA; BIA significantly underestimated %BF as determined by DXA (p <0.0001). Conclusion. The methods used to estimate body composition in healthy preschool children highly correlated. However, the Bland Altman procedure suggests that BIA and DXA should not be used interchangeably.


Subject(s)
Child, Preschool , Child , Absorptiometry, Photon , Anthropometry , Body Composition , Body Mass Index , Weight by Age , Weight by Height , Comparative Study , Cross-Sectional Studies , Epidemiology, Descriptive , Observational Studies as Topic , Data Interpretation, Statistical
8.
ScientificWorldJournal ; 7: 1155-64, 2007 Aug 10.
Article in English | MEDLINE | ID: mdl-17694250

ABSTRACT

Thrombotic microangiopathy and acute renal failure are cardinal features of post-diarrheal hemolytic uremic syndrome (HUS). These conditions are related to endothelial and epithelial cell damage induced by Shiga toxin (Stx), through an interaction with its globotriaosylceramide (Gb3) receptor. Although, Stx is the main pathogenic factor and necessary for HUS development, clinical and experimental evidence suggest that the inflammatory response is able to potentiate Stx toxicity. Lipopolysaccharides (LPS) and neutrophils (PMN) represent two central components of inflammation during a Gram-negative infection. In this regard, patients with high peripheral PMN counts at presentation have a poor prognosis. In the present review, we discuss the contribution of experimental models and patient's studies in an attempt to elucidate the pathogenic mechanisms of HUS.


Subject(s)
Hemolytic-Uremic Syndrome/physiopathology , Neutrophils/physiology , Animals , Disease Models, Animal , Hemolytic-Uremic Syndrome/immunology , Hemolytic-Uremic Syndrome/metabolism , Humans , Lipopolysaccharides/immunology , Lipopolysaccharides/metabolism , Models, Biological , Neutrophils/immunology , Neutrophils/metabolism
9.
Medicina (B Aires) ; 66 Suppl 3: 6-10, 2006.
Article in Spanish | MEDLINE | ID: mdl-17354470

ABSTRACT

Clinical manifestation are described in children with epidemic HUS. The intestinal involvement in the prodromic period, is outlined and the most common disturbances such acute renal failure, thrombocytopenia, hemolytic anemia, leucocitosis hypertension, neurological, pancreatic and cardiac manifestations are described. We discuss the acid-base and electrolyte disturbances, metabolic acidosis, hyponatremia, hyperkalemia. The etiopathogenic treatment and the control of renal sequelae are also discussed.


Subject(s)
Hemolytic-Uremic Syndrome/complications , Hemolytic-Uremic Syndrome/therapy , Acute Disease , Acute Kidney Injury/etiology , Child , Child, Preschool , Diarrhea/complications , Diarrhea/physiopathology , Escherichia coli O157/immunology , Escherichia coli Vaccines/therapeutic use , Female , Hemolytic-Uremic Syndrome/physiopathology , Humans , Hypertension/etiology , Infant , Kidney Transplantation , Male , Prognosis , Thrombocytopenia/etiology , Thrombocytopenia/physiopathology
10.
Medicina (B.Aires) ; 66(supl.2): 6-10, 2006. tab
Article in Spanish | BINACIS | ID: bin-123543

ABSTRACT

Clinical manifestation are described in children with epidemic HUS. The intestinal involvement in the prodromic period, is outlined and the most common disturbances such acute renal failure, thrombocytopenia, hemolytic anemia, leucocitosis hypertension, neurological, pancreatic and cardiac manifestations are described. We discuss the acid-base and electrolyte disturbances, metabolic acidosis, hyponatremia, hyperkalemia. The etiopathogenic treatment and the control of renal sequelae are also discussed.(AU)


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Hemolytic-Uremic Syndrome/complications , Hemolytic-Uremic Syndrome/therapy , Acute Disease , Diarrhea/complications , Diarrhea/physiopathology , Escherichia coli O157/immunology , Escherichia coli Vaccines/therapeutic use , Hemolytic-Uremic Syndrome/physiopathology , Hypertension/etiology , Acute Kidney Injury/etiology , Kidney Transplantation , Prognosis , Thrombocytopenia/etiology , Thrombocytopenia/physiopathology
11.
Medicina (B.Aires) ; 66(supl.2): 6-10, 2006. tab
Article in Spanish | LILACS | ID: lil-480131

ABSTRACT

Clinical manifestation are described in children with epidemic HUS. The intestinal involvement in the prodromic period, is outlined and the most common disturbances such acute renal failure, thrombocytopenia, hemolytic anemia, leucocitosis hypertension, neurological, pancreatic and cardiac manifestations are described. We discuss the acid-base and electrolyte disturbances, metabolic acidosis, hyponatremia, hyperkalemia. The etiopathogenic treatment and the control of renal sequelae are also discussed.


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Hemolytic-Uremic Syndrome/complications , Hemolytic-Uremic Syndrome/therapy , Acute Disease , Acute Kidney Injury , Diarrhea/complications , Diarrhea/physiopathology , /immunology , Escherichia coli Vaccines/therapeutic use , Hemolytic-Uremic Syndrome/physiopathology , Hypertension/etiology , Kidney Transplantation , Prognosis , Thrombocytopenia/etiology , Thrombocytopenia/physiopathology
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