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Etiología de la neumonía en pacientes chilenos infectados por el virus de la inmunodeficiencia humana

2011 , Carlos Pérez C , Patricia García C , Mario Calvo A , Jaime Labarca L , Marisol Bustos M , Teresa Beroíza W , Pablo Gaete G , Rodrigo Moreno B , Guillermo Acuña L , VIAL CLARO, PABLO AGUSTIN

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Serological assays for the detection of human Andes hantavirus infections based on its yeast-expressed nucleocapsid protein

2006-01-01 , Schmidt, Jonas , Meisel, Helga , Capria, Silvana G. , Petraityte, Rasa , Lundkvist, Åke , Hjelle, Brian , VIAL CLARO, PABLO AGUSTIN , Padula, Paula , Krüger, Detlev H. , Ulrich, Rainer

Background: The objective of the study was to develop and evaluate IgM and IgG ELISAs and an IgG Western blottest for the serological detection of human infections with Andes virus (ANDV), the major cause of hantavirus cardiopulmonary syndrome (HCPS) in South America. Methods: The entire nucleocapsid (N) protein-encoding sequence of ANDV (strain AH-1) was cloned and expressed in the yeast Saccharomyces cerevisiae. The polyhistidine-tagged recombinant N (rN) protein of ANDV was purified by nickel-chelation chromatography and characterized by its reactivity with different N-specific monoclonal antibodies. To detect an antibody response directed against ANDV in humans, indirect IgM and IgG ELISAs and an IgG Western blot test based on ANDV rN antigen were developed. The evaluation of the tests was performed using a negative serum panel and 63 blinded sera from Argentina and Chile, containing acute-phase and convalescent sera from HCPS patients. Results: The specificities and sensitivities for the IgM and IgG ELISAs were demonstrated to be very high. The IgG ELISA data were confirmed by the IgG Western blot assay based on the same rN antigen. Almost all anti-ANDV-positive sera reacted to higher endpoint titers with N protein of ANDV than with those of Sin Nombre, Laguna Negra or Puumala virus. The cross-reactivity of anti-ANDV-N IgG-positive sera to rN proteins of other hantaviruses was found to be increased with time after the onset of HCPS. Conclusion: The high sensitivity of the novel assays should facilitate early diagnosis of ANDV infections and might contribute to a successful treatment of HCPS patients. Copyright © 2006 S. Karger AG.

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Platelet Count in Patients with Mild Disease at Admission is Associated with Progression to Severe Hantavirus Cardiopulmonary Syndrome

2019 , LOPEZ HERNANDEZ, RENE RAMON , Mario Calvo , VIAL COX, MARIA CECILIA , Marcela Ferrés , GRAF SANTOS, JERÓNIMO , Gregory Mertz , Analía Cuiza , Begonia Agüero , Dante Aguilera , Diego Araya , Ignacia Pailamilla , Flavia Paratori , Víctor Torres-Torres , VIAL CLARO, PABLO AGUSTIN , DELGADO BECERRA, OROZIMBA IRIS

Background: Hantavirus cardiopulmonary syndrome (HCPS) has a mortality up to 35–40% and its treatment is mainly supportive. A variable to predict progression from mild to severe disease is unavailable. This study was performed in patients with documented infection by Andes orthohantavirus, and the aim was to find a simple variable to predict progression to moderate/severe HCPS in patients with mild disease at admission. Methods: We performed a retrospective analysis of 175 patients between 2001 and 2018. Patients were categorized into mild, moderate, and severe disease according to organ failure and advanced support need at hospital admission (e.g., mechanical ventilation, vasopressors). Progression to moderate/severe disease was defined accordingly. Clinical and laboratory variables associated with progression were explored. Results: Forty patients with mild disease were identified; 14 of them progressed to moderate/severe disease. Only platelet count was different between those who progressed versus those that did not (37 (34–58) vs. 83 (64–177) K/mm3, p < 0.001). A ROC curve analysis showed an AUC = 0.889 (0.78–1.0) p < 0.001, with a platelet count greater than 115K /mm3 ruling out progression to moderate/severe disease. Conclusions: In patients with mild disease at presentation, platelet count could help to define priority of evacuation to tertiary care centers.

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Post-COVID-19 condition: a sex-based analysis of clinical and laboratory trends

2024 , Carlos Delfino , POLI HARLOWE, MARIA CECILIA BERTA , VIAL COX, MARIA CECILIA , VIAL CLARO, PABLO AGUSTIN , Gonzalo Martínez , Amy Riviotta , Catalina Arbat , Nicole Mac-Guire , Josefina Hoppe , CARVAJAL BENAVIDES, CÉSAR CRISTÓBAL , MUÑOZ VENTURELLI, PAULA ANDREA

Background and aimPost-COVID-19 condition (PCC) encompasses long-lasting symptoms in individuals with COVID-19 and is estimated to affect between 31–67% of patients, with women being more commonly affected. No definitive biomarkers have emerged in the acute stage that can help predict the onset of PCC, therefore we aimed at describing sex-disaggregated data of PCC patients from a local cohort and explore potential acute predictors of PCC and neurologic PCC.MethodsA local cohort of consecutive patients admitted with COVID-19 diagnosis between June 2020 and July 2021 were registered, and clinical and laboratory data were recorded. Only those &lt;65 years, discharged alive and followed up at 6 and 12 months after admission were considered in these analyses. Multivariable logistic regression analysis was performed to explore variables associated with PCC (STATA v 18.0).ResultsFrom 130 patients in the cohort, 104 were contacted: 30% were women, median age of 42 years. At 6 months, 71 (68%) reported PCC symptoms. Women exhibited a higher prevalence of any PCC symptom (87 vs. 60%, p = 0.007), lower ferritin (p = 0.001) and procalcitonin (p = 0.021) and higher TNF levels (p = 0.042) in the acute phase compared to men. Being women was independently associated to 7.60 (95% CI 1.27–45.18, p = 0.026) higher risk for PCC. Moreover, women had lower return to normal activities 6 and 12 months.ConclusionOur findings highlight the lasting impact of COVID-19, particularly in young women, emphasising the need for tailored post-COVID care. The lower ferritin levels in women are an intriguing observation, warranting further research. The study argues for comprehensive strategies that address sex-specific challenges in recovery from COVID-19.

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Addition of an arterio-venous shunt during veno-arterial extracorporeal life support in a patient with Hantavirus pulmonary syndrome

2005-11-21 , Tomicic F, Vinko , Espinoza R, Mauricio , Torres M, Javier , Abarca Z, Juan , Montes S, José Miguel , Luppi N, Mario , Concha F, Andrés , Reynolds H, Enrique , Laporte M, Alberto , Canals L, Claudio , VIAL CLARO, PABLO AGUSTIN

A subgroup of patients infected with the Hantavirus develops a pulmonary syndrome (HPS) characterized by severe acute respiratory failure and myocardial depression, that has a high mortality rate. Extracorporeal life support (ECLS) could be a valuable therapeutic tool in such patients. We report a 24 years old male with HPS that was successfully managed when an arterio-venous shunt was added to a conventional veno-arterial ECLS technique. Precise criteria have been developed to predict which patients should be considered for this treatment.

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DNA Vaccine-Generated Duck Polyclonal Antibodies as a Postexposure Prophylactic to Prevent Hantavirus Pulmonary Syndrome (HPS)

2012 , Rebecca Brocato , Matthew Josleyn , John Ballantyne , VIAL CLARO, PABLO AGUSTIN , Jay W. Hooper , Patricia V. Aguilar

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Indirect Immunofluorescence Assay for the Simultaneous Detection of Antibodies against Clinically Important Old and New World Hantaviruses

2013 , Sabine Lederer , Erik Lattwein , Merle Hanke , Karen Sonnenberg , Winfried Stoecker , Åke Lundkvist , Antti Vaheri , Olli Vapalahti , Paul K. S. Chan , Heinz Feldmann , Daryl Dick , Jonas Schmidt-Chanasit , Paula Padula , VIAL CLARO, PABLO AGUSTIN , Raluca Panculescu-Gatej , Cornelia Ceianu , Paul Heyman , Tatjana Avšič-Županc , Matthias Niedrig , Richard Reithinger

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Community acquired infections with methicillin resistant strains of Staphylococcus aureus. Report of five cases

2008 , MUNITA SEPULVEDA, JOSE MANUEL , Noriega Ricalde, Luis Miguel , González, Patricia , Hormazábal, Juan Carlos , Pinto, Consuelo , Magdalena Canals , THOMPSON MOYA, LUIS ADALBERTO , Marcotti, Alejandra , Pérez, Jorge , Ibáñez, Daniel , Araya, Pamela , Canals, Claudio , VIAL CLARO, PABLO AGUSTIN

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Hemodynamic and Pulmonary Permeability Characterization of Hantavirus Cardiopulmonary Syndrome by Transpulmonary Thermodilution

2019 , LOPEZ HERNANDEZ, RENE RAMON , Rodrigo Pérez-Araos , Álvaro Salazar , Ana L. Ulloa , VIAL COX, MARIA CECILIA , VIAL CLARO, PABLO AGUSTIN , GRAF SANTOS, JERÓNIMO

Hantavirus cardiopulmonary syndrome (HCPS) is characterized by capillary leak, pulmonary edema (PE), and shock, which leads to death in up to 40% of patients. Treatment is supportive, including mechanical ventilation (MV) and extracorporeal membrane oxygenation (ECMO). Hemodynamic monitoring is critical to titrate therapy and to decide ECMO support. Transpulmonary thermodilution (TPTD) provides hemodynamic and PE data that have not been systematically used to understand HCPS pathophysiology. We identified 11 HCPS patients monitored with TPTD: eight on MV, three required ECMO. We analyzed 133 measurements to describe the hemodynamic pattern and its association with PE. The main findings were reduced stroke volume, global ejection fraction (GEF), and preload parameters associated with increased extravascular lung water and pulmonary vascular permeability compatible with hypovolemia, myocardial dysfunction, and increased permeability PE. Lung water correlated positively with heart rate (HR, r = 0.20) and negatively with mean arterial pressure (r = −0.27) and GEF (r = −0.36), suggesting that PE is linked to hemodynamic impairment. Pulmonary vascular permeability correlated positively with HR (r = 0.31) and negatively with cardiac index (r = −0.49), end-diastolic volume (r = −0.48), and GEF (r = −0.40), suggesting that capillary leak contributes to hypovolemia and systolic dysfunction. In conclusion, TPTD data suggest that in HCPS patients, increased permeability leads to PE, hypovolemia, and circulatory impairment.

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Granulomatous amebic encephalitis caused by Balamuthia mandrillaris. First case diagnosed in Chile

2006-10-02 , Oddó B., David , Ciani A., Susana , VIAL CLARO, PABLO AGUSTIN

The case of a 7 month-old baby boy is presented, with a history of several weeks of evolution of personality changes, convulsions and fever. While he was hospitalized, the brain image study showed multifocal cavity lesions, which varied from millimeters to 4 cm of diameter, not producing mass effect. Their biopsy revealed necrotizing encephalitis. In spite of treatment, the lesions progressed and the boy died. The autopsy demonstrated an extensive necrotizing encephalitis with fibrinoid necrotic arteritis, signs of organization, and the presence of parasitic elements with characteristics of trophozoites and cysts of free-living amoebas belonging to the genus Acanthamoeba or Balamuthia. In addition, hypoplasia-dysplasia of the thymus and signs of shock were found. The morphologic elements correspond to the disease described as granulomatous amebic encephalitis and the agent found was identified as Balamuthia mandrillaris (Centers for Diseases Control and Prevention, Atlanta, USA).