Patrón de neumonía organizativa en TC de tórax: prevalencia y asociación con resultados clínicos en una cohorte de pacientes con COVID-19 grave/crítico / Organizing Pneumonia Pattern on Chest CT: Prevalence and Association with Clinical Outcomes in a Cohort of Patients with Severe/Critical COVID-19

Introducción: La neumonía por COVID-19 puede presentarse con dos patrones radio-lógicos: daño alveolar difuso o neumonía organizativa. Estos patrones tienen diferente evolución y pronóstico en pacientes sin infección por COVID-19. Nuestro objetivo fue evaluar la prevalencia del patrón radiológico de neumonía organizativa y su asociación con los desenlaces clínicos.Métodos: Se realizó un estudio de cohorte retrospectivo que incluyó a pacientes adultos hospitalizados por COVID-19 grave/crítica a los que se les realizó una tomografía computarizada de tórax en los 21 días posteriores al diagnóstico. Los patrones radiológicos fueron revisados y clasificados por dos radiólogos expertos. Resultados: De los 80 pacientes incluidos, el 89% (n=71) presentaron un patrón compatible con neumonía organizativa. Los principales hallazgos radiológicos fueron la distribución multilobar (98,7%) y bilateral (97,6%) con opacidades en vidrio esmerilado (97,6%). El 44% (n=33) de los sujetos requirió ingreso en cuidados intensivos, de los cuales el 24% (n=19) recibió ventilación mecánica. La presencia de neumonía organizativa se asoció de forma independiente con una disminución de las probabilidades de ventilación mecánica o muerte (Odds ratio 0,14; intervalo de confianza del 95%: 0,02 - 0,96; valor de p 0,045) en un modelo multivariado que incluía la edad, el sexo, el IMC y la afectación pulmonar en la TC.Conclusiones: Un patrón radiológico de neumonía organizativa es altamente prevalen-te en pacientes con COVID-19 grave/crítico y se asocia con mejores resultados clínico

Introduction: COVID-19 pneumonia can present with two distinct radiologic patterns: diffuse alveolar damage or organizing pneumonia. These patterns have been linked to different outcomes in non-COVID-19 settings. We sought to assess the prevalence of organizing pneumonia radiologic pattern and its association with clinical outcomes. Methods: We performed a retrospective cohort study including adult patients hospita- lized for severe/critical COVID-19 who underwent chest computed tomography within 21 days of diagnosis. Radiologic patterns were reviewed and classified by two expert radiologists. Results: Among 80 patients included, 89% (n=71) presented a pattern consistent with organizing pneumonia. The main radiologic findings were multilobar (98.7%) and bilateral (97.6%) distribution with ground glass opacities (97.6%). Intensive care admission was required for 44% (n=33) of subjects, of which 24% (n=19) received mechanical ventilation. The presence of organizing pneumonia was independently associated with a decreased odds of mechanical ventilation or death (Odds ratio 0.14; 95% confidence interval 0.02 - 0.96; p value 0.045) in a multivariate model including age, gender, BMI and lung involvement on CT. Conclusion: A radiologic pattern of organizing pneumonia is highly prevalent in patients with severe/critical COVID-19 and is associated with improved clinical outcomes.

Utilidad del lavado broncoalveolar para la detección microbiológica, y factores asociados, en receptores de trasplante de precursores hematopoyéticos: estudio de cohorte retrospectivo / Usefulness of bronchoalveolar lavage for microbiological detection and asssociated factors in hematopoietic stem cell transplant receivers: a retrospective cohort study

INTRODUCCIÓN: Las opacidades pulmonares en receptores de trasplante de precursores hematopoyéticos (TPH) representan un desafío diagnóstico y son una causa de morbimortalidad. Existen grandes discrepancias con respecto a la sensibilidad diagnóstica del lavado broncoalveolar (LBA), sus complicaciones, y los factores asociados a la identificación microbiológica. OBJETIVO: Conocer la utilidad del estudio microbiológico del LBA en el diagnóstico, modificación de la conducta médica y estimar las complicaciones y mortalidad asociada al procedimiento, en receptores de TPH con opacidades pulmonares. PACIENTES Y MÉTODOS: Estudio de cohorte, retrospectivo, en adultos receptores de TPH a los que se les realizó una broncoscopía con LBA por presentar opacidades pulmonares, en el Hospital Italiano de Buenos Aires entre el 01/01/2011 y el 31/12/2020. RESULTADOS: De los 189 procedimientos analizados, en 79 se logró un hallazgo microbiológico (41,8%) y 122 permitieron modificar la conducta médica (64,6%). En 11 casos se observaron complicaciones graves dentro de las 12 horas (5,8%) de efectuado el LBA. La mortalidad intrahospitalaria fue de 16,8% (N = 21/125). El valor de neutrófilos en sangre previo al LBA (p = 0,037) y la presencia de nódulos pulmonares como lesión tomográfica predominante (p = 0,029) se asociaron independientemente al hallazgo microbiològico global. CONCLUSIONES: Nuestra investigación apoya la realización del LBA como herramienta diagnóstica en pacientes que reciben un TPH y presentan opacidades pulmonares.

BACKGROUND: Lung opacities are a cause of morbimortality in bone marrow transplant patients, and represent a diagnostic challenge. There are large discrepancies regarding the diagnostic sensitivity of bronchoalveolar lavage (BAL), its complications, and the factors associated with microbiological detection. AIM: To know the usefulness of the microbiological study of BAL in the diagnosis, in the modification in medical behavior and to estimate the complications and associated mortality of this diagnostic procedure in patients transplanted with hematopoietic progenitor cells with pulmonary opacities. METHODS: Retrospective cohort study in bone marrow transplant adult patients who underwent bronchoscopy with BAL due to lung opacities at Hospital Italiano de Buenos Aires between 01/01/2011 and 12/31/2020. RESULTS: Of the 189 BAL analyzed, 79 presented a microbiological detection (41.8%) and 122 allowed to modify the medical behavior (64.6%). Severe complications were observed within 12 hours after the procedure in11 cases (5.8%). In-hospital mortality was 16,8% (N = 21/125). The value of blood neutrophils prior to bronchoalveolar lavage (p = 0.037) and the presence of pulmonary nodules as the predominant tomographic lesion (p = 0.029) were independently associated with global microbiological detection. CONCLUSION: Our research supports the performance of BAL as a diagnostic tool in bone marrow transplant patients with lung opacities.

[Chronic eosinophilic pneumonia: imaging findings]. / Neumonía eosinofílica crónica: hallazgos en imágenes.

Chronic eosinophilic pneumonia (CEP) is a rare disease of unknown cause characterized by alveolar and interstitial eosinophilic infiltration. The tomographic pattern is characterized by consolidations and peripherally distributed ground glass opacities in both upper lobes. Other findings are opacities in bands parallel to the pleura, thickening of the interlobular septa, migratory opacities, and mediastinal lymph nodes. We presented a case of a woman with CEP and described the most relevant clinical and radiological characteristics.

La neumonía eosinofílica crónica (NEC) es una enfermedad rara de causa desconocida caracterizada por infiltración eosinofílica alveolar e intersticial. El patrón tomográfico se caracteriza por consolidaciones y opacidades en vidrio esmerilado de distribución periférica en ambos lóbulos superiores. Otros hallazgos son las opacidades en bandas paralelas a la pleura, engrosamiento de septos interlobulillares, opacidades migratrices y adenomegalias mediastinales. Se presenta el caso de una mujer con NEC y se describen las características clínicas y radiológicas más relevantes.

Thrombotic events following Covid-19 vaccines compared to Influenza vaccines.

IMPORTANCE: The actual risk of thrombotic events after Covid-19 vaccination is unknown. OBJECTIVE: To evaluate the risk of thrombotic events after Covid-19 vaccination. DESIGN: Retrospective cohort study which included consecutive adult patients vaccinated with the first dose of Covid-19 vaccine between January 1 and May 30, 2021, and a historic control group, defined as consecutive patients vaccinated with influenza vaccine between March 1 and July 30, 2019. SETTING: Hospital Italiano de Buenos Aires, a tertiary hospital in Argentina. PARTICIPANTS: Non-Hospitalized Adults vaccinated with the first dose of a Covid-19 vaccine. EXPOSURE: Vaccination with Covid-19 vaccines available during the study period: Gam-COVID-Vac (Sputnik), ChAdOx1 nCoV-19 (AstraZeneca/Oxford or Covishield), BBIBP-CorV (Beijing Institute of Biological Products) (Sinopharm). Active comparator group exposure was Influenza vaccine. MAIN OUTCOME: Primary endpoint was cumulative incidence of any symptomatic thrombotic event at 30 days, defined as the occurrence of at least one of the following: symptomatic acute deep venous thrombosis (DVT); symptomatic acute pulmonary embolism (PE); acute ischemic stroke (AIS); acute coronary syndrome (ACS) or arterial thrombosis. RESULTS: From a total of 29,985 adult patients who received at least a first dose of Covid-19 vaccine during study period and 24,777 who received Influenza vaccine in 2019, we excluded those who were vaccinated during hospitalization. We finally included 29,918 and 24,753 patients respectively. Median age was 73 years old (IQR 75-81) and 67% were females in both groups. Thirty six subjects in the Covid-19 vaccination group (36/29,918) and 15 patients in the Influenza vaccination group (15/24,753) presented at least one thrombotic event. The cumulative incidence of any thrombotic event at 30 days was 12 per 10,000 (95%CI 9-17) for Covid-19 group and 6 per 10,000 (95%CI 4-10) for Influenza group (p-value=0.022). CONCLUSIONS AND RELEVANCE: This study shows a significant increase in thrombotic events in subjects vaccinated with Covid-19 vaccines in comparison to a control group. The clinical implication of these findings should be interpreted with caution, in light of the high effectiveness of vaccination and the inherent risk of thrombosis from Covid-19 infection itself.

Incidence of COVID-19 after pulmonary function tests: a retrospective cohort study.

INTRODUCTION: It has been proposed that exposure to pulmonary function tests (PFT) could be associated with a higher risk of viral transmission. The risk of the Coronavirus Disease 2019 (COVID-19) transmission after performing PFT is unknown. We aimed to assess the incidence  of COVID-19 after a PFT at an academic teaching facility in Buenos Aires, Argentina. MATERIALS AND METHODS: We conducted a retrospective cohort study including all consecutive adult patients that performed PFT between April 1, 2020 and September 30, 2020. Patients with prior COVID-19 were excluded. We defined a 15-day time window to  ascertain PFT related COVID-19. The primary outcome was ascertained by consulting a national database, which has information on all patients with nasopharyngeal swabs for SARS-CoV-2 in Argentina. RESULTS: We included 278 patients who performed a PFT. Fifty percent were women, the mean age was 54 years (SD 18), and the main comorbidities were obesity (31%), smoking (31%), hypertension (29%), and chronic lung disease (28%). The main indication for performing PFT was anesthetic preoperative risk assessment. Swabs were collected from 27 patients (10%). Twenty-two swabs (8%) were taken according to surgical protocols; five swabs (2%) were taken due to clinical suspicion of COVID-19, with only one testing positive. The cumulative incidence of COVID-19 after PFT was 0.36% (95% CI 0.01-20%). None of the technicians developed symptomatic disease. CONCLUSION: Given the right setting and strict adherence to international recommendations, the SARS-CoV-2 infection after having a PFT appears to be low, which follows that these procedures can be performed safely for both patients and staff.

Introducción: Se ha propuesto que las pruebas de función respiratorias (PFR) podrían estar asociadas con un mayor riesgo de transmisión viral. El riesgo de presentar la enfermedad por coronavirus 2019 (COVID-19) después de realizar una PFR es desconocido. El objetivo del estudio fue estimar la incidencia de COVID-19 después de llevar a cabo una PFR, en un Hospital Universitario de la ciudad Autónoma de Buenos Aires, Argentina. Se realizó una cohorte retrospectiva que incluyó a todos los pacientes que realizaron una PFR entre el 1 de abril de 2020 y el 30 de septiembre de 2020. Se excluyeron los pacientes con antecedentes de COVID-19. Definimos una ventana de tiempo de 15 días para determinar la presencia de COVID-19 relacionada con la realización de la PFR. El resultado primario se determinó consultando una base de datos nacional, que contiene información sobre todos los pacientes que se han realizado hisopados nasofaríngeos para detección del SARS-CoV-2 en Argentina. Materiales y métodos: Se incluyeron 278 pacientes, el 50% fueron mujeres, el promedio de edad fue de 54 años (DE 18) y las principales comorbilidades fueron: obesidad (31%), tabaquismo (31%), hipertensión (29%) y enfermedades respiratorias crónicas (28%). La principal indicación de la PFR fue la evaluación pre operatoria o anestésica. A 27 pacientes (10%) se les realizó un hisopado nasofaríngeo para búsqueda de SARS-CoV-2. Veintidós hisopados (8%) se solicitaron por evaluación pre quirúrgica, cinco hisopados (2%) por sospecha clínica de infección y solamente uno fue positivo. La incidencia de COVID-19 fue de 0.36% (IC95% 0.01-20%). Durante el período del estudio ninguno de los operadores que realizaron las PFR presentaron síntomas compatibles con COVID-19. Conclusión: Siguiendo las recomendaciones internacionales, la frecuencia de detección de COVID-19 después de las PFR parece ser bajo, por lo que estos procedimientos se podrían llevar a cabo de forma segura tanto para los pacientes como para el personal.

A practical artificial intelligence system to diagnose COVID-19 using computed tomography: A multinational external validation study.

Computed tomography has gained an important role in the early diagnosis of COVID-19 pneumonia. However, the ever-increasing number of patients has overwhelmed radiology departments and has caused a reduction in quality of services. Artificial intelligence (AI) systems are the remedy to the current situation. However, the lack of application in real-world conditions has limited their consideration in clinical settings. This study validated a clinical AI system, COVIDiag, to aid radiologists in accurate and rapid evaluation of COVID-19 cases. 50 COVID-19 and 50 non-COVID-19 pneumonia cases were included from each of five centers: Argentina, Turkey, Iran, Netherlands, and Italy. The Dutch database included only 50 COVID-19 cases. The performance parameters namely sensitivity, specificity, accuracy, and area under the ROC curve (AUC) were computed for each database using COVIDiag model. The most common pattern of involvement among COVID-19 cases in all databases were bilateral involvement of upper and lower lobes with ground-glass opacities. The best sensitivity of 92.0% was recorded for the Italian database. The system achieved an AUC of 0.983, 0.914, 0.910, and 0.882 for Argentina, Turkey, Iran, and Italy, respectively. The model obtained a sensitivity of 86.0% for the Dutch database. COVIDiag model could diagnose COVID-19 pneumonia in all of cohorts with AUC of 0.921 (sensitivity, specificity, and accuracy of 88.8%, 87.0%, and 88.0%, respectively). Our study confirmed the accuracy of our proposed AI model (COVIDiag) in the diagnosis of COVID-19 cases. Furthermore, the system demonstrated consistent optimal diagnostic performance on multinational databases, which is critical to determine the generalizability and objectivity of the proposed COVIDiag model. Our results are significant as they provide real-world evidence regarding the applicability of AI systems in clinical medicine.

Long covid: cross sectional study / [Covid prolongado: estudio de corte transversal]

Introduction: Coronavirus disease 2019 (COVID-19) is a public health problem worldwide. After 3 weeks of the onset of the disease, between 10-87% of patients persist with symptoms. The objective of the study was to evaluate the persistence of symptoms in patients with COVID-19, the associated factors, and to explore the patients' perception of the disease. Materials and methods: We conducted a cross-sectional study that included 85 patients with a confirmed diagnosis of COVID-19, who attended on an outpatient basis after the acute phase (> 3 weeks) of the disease. Results: The median time from diagnosis to outpatient consultation was 53 days (interquartile range 31-65). Most (86%) had mild disease, 45% were women and the mean age was 43 years (standard deviation of 13). After the acute phase of the disease 52% (95% CI 41-63%) of the patients persisted with symptoms. The most frequently persistent symptoms were fatigue (49%) and cough (33%). Nineteen percent had insomnia and sixteen percent had anxiety. Female sex, obesity, age between 35-55 years, and initial hospitalization were associated with the persistence of symptoms. Twenty percent of the patients stopped following the prevention recommendations because they believed they were immunized. Conclusion: More than half of the patients persisted with symptoms 3 weeks after the COVID-19 diagnosis, so medical follow-up is important. Female sex, obesity, age 35-55 years, and initial hospitalization were associated factors. The symptoms usually resolved over time.

Introducción: La enfermedad por Coronavirus 2019 (COVID-19) es un problema de salud pública a nivel mundial. Posterior a las 3 semanas de iniciado el cuadro entre un 10-87% de los pacientes persisten con síntomas. El objetivo del estudio fue evaluar la persistencia de los síntomas en pacientes que presentaron la COVID-19, los factores asociados y explorar la percepción de los pacientes sobre la enfermedad. Materiales y Métodos: Se realizó un estudio de corte transversal que incluyó 85 pacientes con diagnóstico confirmado de COVID-19, que consultaron en forma ambulatoria posterior a la fase aguda (> 3 semanas) de la enfermedad. Resultados: La mediana de tiempo desde el diagnóstico a la consulta ambulatoria fue de 53 días (rango inter cuartil 31-65). La mayoría (86%) presentó un cuadro leve y no requirió internación. El 45% eran mujeres y la media de edad fue de 43 años (desvío estándar de 13). El 52% (IC95% 41-63%) de los pacientes persistían con síntomas más allá de la fase aguda de la enfermedad. El síntoma que persistió con más frecuencia fue la fatiga (49%) seguida de la tos (33%). El 19% presentó insomnio y el 16% tenía ansiedad. El sexo femenino, la obesidad, la edad entre 35-55 años y la hospitalización inicial, se asociaron a la persistencia de los síntomas. Un 20% de los pacientes dejó de seguir las recomendaciones de prevención porque creía estar inmunizado. Conclusión: Más de la mitad de los pacientes persistían con síntomas posterior a las 3 semanas del diagnóstico de COVID-19. El sexo femenino, la obesidad, la edad 35-55 años y la hospitalización inicial fueron factores asociados. Los síntomas se fueron resolviendo con el transcurso del tiempo.

Diagnosis of pulmonary embolism in patients with acute exacerbations of chronic obstructive pulmonary disease: A cross-sectional study.

INTRODUCTION: Pulmonary embolism (PE) remains a frequent complication in patients with chronic obstructive pulmonary disease (COPD). It is unclear that the extent to which the traditional risk stratifying scores for PE are accurate in this population. METHODS: Cross-sectional study of adult patients with COPD and suspected PE included in an Institutional Registry of Thromboembolic Disease at a tertiary teaching hospital in the city of Buenos Aires, Argentina. We estimated the area under the receiver operating characteristic curves (AU-ROC), sensitivity and specificity of the Wells and Geneva scores using a positive computed tomography angiography as the gold standard for PE. We also estimated the sensitivity and specificity for the presence of isolated worsening of dyspnea at presentation, without other cardinal symptoms of acute exacerbation of COPD. RESULTS: A total of 168 patients were included, of which 22% had confirmed PE. The AUC was 0.66 (95% CI 0.56-0.76) and 0.56 (95% CI 0.45-0.67) for the Wells and Geneva, respectively. Considering the most widely used cutoff points, the sensitivity and specificity were 24% and 90% for the Wells and 59% and 43% for the Geneva score, respectively. Isolated worsening of dyspnea on presentation had a sensitivity of 92% and specificity of 37%. CONCLUSIONS: Both Wells and Geneva scores exhibit poor diagnostic accuracy for the diagnosis of PE in patients with COPD. The presence of isolated worsening of dyspnea on presentation could be an easy to identify criteria for the initial triage in this population. Further validation of our findings remains warranted.

[COVID-19 pneumonia: Tomographic findings]. / Neumonía por COVID-19: hallazgos tomográficos.

Coronavirus disease (COVID-19) has spread worldwide and has become a priority health problem. We described a case of a patient with COVID-19 and the main characteristics of imaging findings.

La enfermedad por coronavirus (COVID-19) se ha expandido mundialmente y convertido en un problema prioritario de salud a nivel mundial. Se presenta el caso de un paciente con COVID-19 y se describen las características radiológicas más relevantes.