Browsing by Author "Iruretagoyena, Mirentxu"
Now showing 1 - 11 of 11
Results Per Page
Sort Options
Item Comparative evaluation of four rapid SARS-CoV-2 antigen detection tests using universal transport medium(2021) Weitzel, Thomas; Legarraga, Paulette; Iruretagoyena, Mirentxu; Pizarro, Gabriel; Vollrath, Valeska; Araos, Rafael; Munita, José; Porte, LorenaCorrespondencePublication Enfermedad relacionada a IgG4. Serie clínica de pacientes chilenos(2022) Cuéllar, María C.; Gutiérrez, Miguel; Herrera, Alejandra; Elgueta, Fabián; Wurmann, Pamela; Badilla, Natalia; Mansilla, Bellanides; Basualdo, Javier; Vega, Jorge; Erlij, Daniel; Labarca, Cristian; Vergara, Cristian; Mezzano, Verónica; Méndez, Ignacio; Stange, Lilith; Michalland, Susana; Silva, Francisco; Jara, Aquiles; Goecke, Annelise; Burgos, Paula; Iruretagoyena, Mirentxu; Fernández, Cristina; Landeros, Carolina; Neira Quiroga, OscarBackground: IgG4-related disease (IgG4 RD) is an immune-mediated fibro-inflammatory disorder, with tissue infiltration of IgG4+ plasma cells. It causes pseudotumors, tumors, and a wide spectrum of clinical manifestations. Aim: To report the clinical, laboratory, histopathological and treatment characteristics of a group of Chilean patients with IgG4 RD. Material and Methods: Review of medical records of 52 patients aged 18 to 76 years with IgG4 RD seen at six medical centers. Results: Elevated IgG4 serum levels (> 135 mg/dl) were found in 18 of 44 (41%) patients. There was histological confirmation of the disease in 46 patients. The most common sites of involvement were lungs, eyes and kidneys. Eighteen (35%) patients had only one organ involved, 34 (65%) patients had two organs and 13 (25%) patients had three or more organs. The involvement of two organs was significantly more common in men (p < 0.05). In patients with only one organ involvement, the most frequent location was orbital and meningeal. All patients with kidney or lung disease had multiorgan involvement. All patients received corticosteroid therapy, 67% synthetic immunosuppressants, and 16% rituximab. Conclusions: ER-IgG4 can affect any tissue. Multiorgan involvement was more common in this series, with preference for lungs, eyes and kidneys. An excellent response to steroids is characteristic of the disease, but with a high relapse rate that requires additional immunosuppression.Item Esofagitis eosinofílica: diagnóstico y manejo(2021) Ballart, María Jesús; Monrroy, Hugo; Iruretagoyena, Mirentxu; Parada, Alejandra; Torres, Javiera; Espino, AlbertoEosinophilic esophagitis (EoE) is a chronic, immune-mediated disease, induced by food allergens, clinically characterized by symptoms of esophageal dysfunction. Pathologically there is a predominant eosinophilic inflammation. This disease is relatively new, and its definitions have evolved over time. Its prevalence and incidence are increasing and causes clinical problems both in children and adults. Its symptoms include food impaction, dysphagia, symptoms that resemble gastroesophageal reflux, abdominal pain, and vomiting. It can also have extra-digestive symptoms such as rhinosinusitis, chronic cough, recurrent croup and hoarseness. EoE can be associated with other atopic conditions, such as asthma, eczema and food allergies. The diagnosis is made by the analysis of endoscopic biopsies (> 15 eosinophils per high power field). Proton pump inhibitors (PPIs) are currently accepted as a treatment for EoE. The clinical and pathological improvement with the use PPIs ceased to be a criterion to define Esophageal eosinophilia responsive to PPIs as a differential diagnosis, since this condition is currently considered within the EoE spectrum. There are three main treatment approaches for EoE: diet, drugs and dilation. Its diagnosis and early treatment are key to avoid or delay its complications, such as stenosis and severe esophageal dysfunction.Item Esofagitis eosinofílica: diagnóstico y manejo(2020) Ballart, María Jesús; Monrroy, Hugo; Iruretagoyena, Mirentxu; Parada, Alejandra; Torres, Javiera; Espino, Albertoinduced by food allergens, clinically characterized by symptoms of esophageal dysfunction. Pathologically there is a predominant eosinophilic inflammation. This disease is relatively new, and its definitions have evolved over time. Its prevalence and incidence are increasing and causes clinical problems both in children and adults. Its symptoms include food impaction, dysphagia, symptoms that resemble gastroesophageal reflux, abdominal pain, and vomiting. It can also have extra-digestive symptoms such as rhinosinusitis, chronic cough, recurrent croup and hoarseness. EoE can be associated with other atopic conditions, such as asthma, eczema and food allergies. The diagnosis is made by the analysis of endoscopic biopsies (> 15 eosinophils per high power field). Proton pump inhibitors (PPIs) are currently accepted as a treatment for EoE. The clinical and pathological improvement with the use PPIs ceased to be a criterion to define Esophageal eosinophilia responsive to PPIs as a differential diagnosis, since this condition is currently considered within the EoE spectrum. There are three main treatment approaches for EoE: diet, drugs and dilation. Its diagnosis and early treatment are key to avoid or delay its complications, such as stenosis and severe esophageal dysfunction.Item Evaluation of a novel antigen-based rapid detection test for the diagnosis of SARS-CoV-2 in respiratory samples(2020) Porte, Lorena; Legarraga, Paulette; Vollrath, Valeska; Aguilera, Ximena; Munita, José; Araos, Rafael; Pizarro, Gabriel; Vial, Pablo; Iruretagoyena, Mirentxu; Dittrich, Sabine; Weitzel, ThomasObjectives: In the context of the coronavirus disease 2019 (COVID-19) pandemic, the development and validation of rapid and easy-to-perform diagnostic methods are of high priority. This study was performed to evaluate a novel rapid antigen detection test (RDT) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in respiratory samples. Methods: The fluorescence immunochromatographic SARS-CoV-2 antigen test (Bioeasy Biotechnology Co., Shenzhen, China) was evaluated using universal transport medium with nasopharyngeal (NP) and oropharyngeal (OP) swabs from suspected COVID-19 cases. Diagnostic accuracy was determined in comparison to SARS-CoV-2 real-time (RT)-PCR. Results: A total of 127 samples were included; 82 were RT-PCR-positive. The median patient age was 38 years, 53.5% were male, and 93.7% were from the first week after symptom onset. Overall sensitivity and specificity were 93.9% (95% confidence interval 86.5-97.4%) and 100% (95% confidence interval 92.1-100%), respectively, with a diagnostic accuracy of 96.1% and Kappa coefficient of 0.9. Sensitivity was significantly higher in samples with high viral loads. Conclusions: The RDT evaluated in this study showed a high sensitivity and specificity in samples mainly obtained during the first week of symptoms and with high viral loads, despite the use of a non-validated sample material. The assay has the potential to become an important tool for early diagnosis of SARS-CoV-2, particularly in situations with limited access to molecular methods.Item Evaluation of two fluorescence immunoassays for the rapid detection of SARS-CoV-2 antigen-new tool to detect infective COVID-19 patients(2021) Porte, Lorena; Legarraga, Paulette; Iruretagoyena, Mirentxu; Vollrath, Valeska; Pizarro, Gabriel; Munita, José; Araos, Rafael; Weitzel, ThomasBackground Real-Time Reverse-Transcription Polymerase Chain Reaction (RT-PCR) is currently the only recommended diagnostic method for SARS-CoV-2. However, rapid immunoassays for SARS-CoV-2 antigen could significantly reduce the COVID-19 burden currently weighing on laboratories around the world. Methods We evaluated the performance of two rapid fluorescence immunoassays (FIAs), SOFIA SARS Antigen FIA (Quidel Corporation, San Diego, CA, USA) and STANDARD F COVID-19 Ag FIA (SD Biosensor Inc., Gyeonggi-do, Republic of Korea), which use an automated reader. The study used 64 RT-PCR characterized clinical samples (32 positive; 32 negative), which consisted of nasopharyngeal swabs in universal transport medium. Results Of the 32 positive specimens, all from patients within 5 days of symptom onset, the Quidel and SD Biosensor assays detected 30 (93.8%) and 29 (90.6%) samples, respectively. Among the 27 samples with high viral loads (Ct ≤ 25), the two tests had a sensitivity of 100%. Specificity was 96.9% for both kits. Conclusion The high performance of the evaluated FIAs indicates a potential use as rapid and PCR-independent tools for COVID-19 diagnosis in early stages of infection. The excellent sensitivity to detect cases with viral loads above ~106 copies/mL (Ct values ≤ 25), the estimated threshold of contagiousness, suggests that the assays might serve to rapidly identify infective individuals.Item First Report of Tocilizumab Use in a Cohort of Latin American Patients Hospitalized for Severe COVID-19 Pneumonia(2020) Valenzuela, Omar; Ibáñez, Sebastián; Poli, Cecilia; Roessler, Patricia; Aylwin, Mabel; Roizen, Gigia; Iruretagoyena, Mirentxu; Agar, Vivianne; Donoso, Javiera; Fierro, Margarita; Montes, José MiguelIntroduction/objectives: An interleukin-6 inhibition strategy could be effective in selected COVID-19 patients. The objective is to present our experience of tocilizumab use in patients with severe COVID-19. Methods: Observational retrospective cohort study. Hospitalized patients were evaluated by our multidisciplinary team for eventual use of tocilizumab. Patients with progressive ventilatory impairment and evidence of a hyperinflammatory state despite usual treatment received tocilizumab 8 mg/kg intravenous (maximum dose 800 mg), in addition to standard treatment. The use and time of use of mechanical ventilation (MV), the change of the Alveolar-arterial (A-a) gradient, of the ratio of arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FiO2) and of inflammation laboratory parameters after 72 h of tocilizumab use was evaluated. Results: 29 patients received tocilizumab. 93.1% were men, 37.9% were obese, and 34.5% had hypertension. Of the 20 patients who were not on MV when receiving tocilizumab, 11 required non-invasive MV, for an average of 5 days, and one of them required intubation. A-a gradient, PaO2/FiO2, and inflammation parameters improved significantly. A better lymphocyte count, which improved significantly after tocilizumab use, was significantly associated with less use of MV. Five patients presented positive culture samples after tocilizumab, three being of clinical significance. A lower lymphocyte count was associated with having a positive culture. No other significant adverse events were seen. Conclusion: Our study suggests the utility and shows the safety of tocilizumab use in COVID-19 patients who have respiratory failure and evidence of hyperinflammation. Lymphocyte improvement was a predictor of good response.Item First Report of Tocilizumab Use in a Cohort of Latin American Patients Hospitalized for Severe COVID-19 Pneumonia(2020) Valenzuela, Omar; Ibáñez, Sebastián; Poli, Cecilia; Roessler, Patricia; Aylwin, Mabel; Roizen, Gigia; Iruretagoyena, Mirentxu; Agar, Vivianne; Donoso, Javiera; Fierro, Margarita; Montes, JoséIntroduction/objectives: An interleukin-6 inhibition strategy could be effective in selected COVID-19 patients. The objective is to present our experience of tocilizumab use in patients with severe COVID-19. Methods: Observational retrospective cohort study. Hospitalized patients were evaluated by our multidisciplinary team for eventual use of tocilizumab. Patients with progressive ventilatory impairment and evidence of a hyperinflammatory state despite usual treatment received tocilizumab 8 mg/kg intravenous (maximum dose 800 mg), in addition to standard treatment. The use and time of use of mechanical ventilation (MV), the change of the Alveolar-arterial (A-a) gradient, of the ratio of arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FiO2) and of inflammation laboratory parameters after 72 h of tocilizumab use was evaluated. Results: 29 patients received tocilizumab. 93.1% were men, 37.9% were obese, and 34.5% had hypertension. Of the 20 patients who were not on MV when receiving tocilizumab, 11 required non-invasive MV, for an average of 5 days, and one of them required intubation. A-a gradient, PaO2/FiO2, and inflammation parameters improved significantly. A better lymphocyte count, which improved significantly after tocilizumab use, was significantly associated with less use of MV. Five patients presented positive culture samples after tocilizumab, three being of clinical significance. A lower lymphocyte count was associated with having a positive culture. No other significant adverse events were seen. Conclusion: Our study suggests the utility and shows the safety of tocilizumab use in COVID-19 patients who have respiratory failure and evidence of hyperinflammation. Lymphocyte improvement was a predictor of good response.Publication Immune response against SARS-CoV-2 of primary healthcare personnel in a commune of Santiago, Chile: follow-up at 6 months(2022) Matute, Isabel; Hirmas, Macarena; González, Claudia; Iruretagoyena, Mirentxu; Munita, José; Pedroni, Elena; Gómez, María; Córtez, L.; Hormazábal, J.; Olea, AndreaBackground The COVID-19 pandemic that emerged in Wuhan, China at the end of 2019, spread rapidly around the world with almost 600 million cases and 6.3 million deaths today. The most affected were health workers with at least three times the risk of contracting the disease than the general community. Most studies on seroprevalence in health workers focus on hospital care establishments and what happens in Primary Health Care (PHC) has not been investigated with the same intensity. Objectives to determine the prevalence and know the variation of antibody titers for SARS-CoV-2 in serial samples of primary healthcare personnel from the commune of La Pintana. Method an analytical observational study with a cross-sectional and a longitudinal component, carried out from November 2020 to June 2021. The first component consisted of an IgG antibody seroprevalence study performed at baseline (time 0) in volunteer of a universe of 900 workers. The longitudinal component considered the monitoring of IgG antibodies in those who presented a positive result at baseline and the analysis of neutralizing antibodies in a random sub-sample of 50% of them. Additionally, sociodemographic and clinical information was collected via a questionnaire. Univariate, bivariate, and longitudinal analyses were performed to evaluate differences in antibodies. The study was approved by the Universidad del Desarrollo’s Scientific Ethics Committee. Results 463 primary healthcare workers participated, mostly women and with a median of 38 years; doctors and nurses represented 9.5% each and 14.7% had a history of COVID-19. The seroprevalence at baseline was 22.3% and was associated with younger age, being a doctor and having been in close contact of a case. IgG titers increased with the vaccine, but decreased over time. At the 6-month follow-up, 76% had neutralizing antibodies. Those belonging to indigenous peoples had higher IgG levels and higher rates of neutralizing antibodies. Conclusion Healthcare workers were highly affected by COVID-19, and the medical profession and younger age were factors associated with increased risk. Antibodies decrease over time, highlighting the importance of follow-up studies, as well as the importance of vaccination boosters in healthcare workers, especially those in PHC.Item Longitudinal assessment of SARS-CoV-2 IgG seroconversionamong front-line healthcare workers during the first wave of the Covid 19 pandemic at a tertiary-care hospital in Chile(2021) Iruretagoyena, Mirentxu; Vial, Macarena; Spencer-Sandino, Maria; Gaete, Pablo; Peters, Anne; Delgado, Iris; Perez, Inia; Calderón, Claudia; Porte, Lorena; Legarraga, Paulette; Anderson, Alicia; Aguilera, Ximena; Vial, Pablo; Weitzel, Thomas; Munita, JoséBackground: Healthcare workers (HCWs) are at high risk of exposure to SARS-CoV-2. Cross-sectional studies have provided variable rates of seroprevalence in HCWs. Longitudinal assessments of the serological response to Covid 19 among HCWs are crucial to understanding the risk of infection and changes in antibody titers over time. We aimed to investigate seroprevalence and risk factors associated with seroconversion in a prospective cohort of HCWs during the peak of the first wave of the Covid-19 pandemic. Methods: We conducted a longitudinal study among 446 front-line HCWsin a tertiary-care hospital in Chile from April to July 2020. IgG was determined monthly using two different ELISAs in serum samples of HCWs, during the three-month period. In each visit, demographic data, symptoms, risk factors, and exposure risks were also assessed. Results: The overall seroprevalence at the end of the study period was 24% (95% CI20.2–28.3), with 43% of seropositive HCWs reporting no prior symptoms. Seroconversion rates significantly differed over the study period, from 2.1% to as high as 8.8% at the peak of the epidemic. There were no statistically significant differences observed between HCWs in direct clinical care of patients with Covid-19 and those working in low risk areas. Antibody titers appeared to wane over time. Conclusions: HCWs were severely affected with a high rate of seroconversion that appeared to mirror the local epidemiological situation. A significant amount of participants underwent an asymptomatic infection, highlighting the need for improved surveillance policies. Antibody titers appear to wane over time; further studies to understand this finding’s impact on the risk of reinfection are warrantedPublication Respuesta inmunitaria al SARS-CoV-2 y factores asociados previo a la vacunación, en personal de salud de atención primaria en una comuna de Santiago, Chile(2022) Olea, Andrea; Matute, Isabel; Hirmas, Macarena; González, Claudia; Iruretagoyena, Mirentxu; Munita, José; Pedroni, Elena; Gómez, María; Nájera, ManuelIntroducción: La pandemia de COVID-19 surgida en China a fines de 2019, se extendió rápidamente por el mundo, con casi 600 millones de casos y 6,3 millones de fallecidos en la actualidad. Los más afectados fueron los trabajadores de la salud con al menos tres veces más riesgo que la comunidad general de contraer la enfermedad. La mayoría de los estudios sobre seroprevalencia en trabajadores de la salud, se enfocan en establecimientos de atención hospitalaria y no se ha indagado con igual intensidad sobre lo que ocurre en la Atención Primaria de Salud (APS). Objetivos: Determinar prevalencia de SARS-CoV-2 mediante anticuerpos IgG en personal de atención primaria de comuna de La Pintana y explorar sus características clínicas y factores de riesgo, previo a la vacunación en Chile. Metodología: Diseño transversal realizado en noviembre 2020. Se recogieron datos sociodemográficos y clínicos mediante entrevista cara a cara, previa firma de consentimiento. Se determinó IgG específica mediante ELISA que utiliza proteína N y S. Las diferencias entre sujetos positivos y negativos se estudiaron mediante análisis bivariado y para asociaciones encontradas, se desarrollaron modelos multivariados controlando potenciales variables de confusión. El estudio contó con la aprobación del Comité Ético Científico de la Universidad del Desarrollo. Resultados: Participaron 463 funcionarios (51,4%) encontrando prevalencia de 21,8%. Los factores de riesgo fueron edad menor, ser médico y haber sido contacto estrecho de un caso. El 22% fue asintomático. Entre quienes presentan anosmia o ageusia, la probabilidad de IgG+ fue superior a 70%. Los títulos de anticuerpos aumentan significativamente con la gravedad. Conclusiones: La prevalencia en personal de atención primaria encontrada es concordante con la evidencia previa en trabajadores de salud. La menor edad y la profesión de médico se asocian a un mayor riesgo de enfermar.