Differences in Exercise Capacity, Ventilatory Efficiency, and Gas Exchange between Patients with Pulmonary Arterial Hypertension and Chronic Thromboembolic Pulmonary Hypertension Residing at High Altitude.

Background: Cardiopulmonary exercise testing (CPET) assesses exercise capacity and causes of exercise limitation in patients with pulmonary hypertension (PH). At altitude, changes occur in the ventilatory pattern and a decrease in arterial oxygen pressure in healthy; these changes are increased in patients with cardiopulmonary disease. Our objective was to compare the response to exercise and gas exchange between patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) residing at the altitude of Bogotá (2640 m). Methods: All patients performed an incremental CPET with measurement of oxygen consumption ( VO 2 ), dead space (VD/VT), ventilatory equivalents (VE/ VCO 2 ), and alveolar-arterial oxygen gradient ( PA-aO 2 ). X 2 test and one-way analysis of variance were used for comparisons between PAH and CTEPH. Results: We included 53 patients, 29 with PAH, 24 with CTEPH, and 102 controls as a reference of the normal response to exercise at altitude. CTEPH patients had a higher New York Health Association (NYHA) functional class than PAH (p = 0.037). There were no differences between patients with PAH and CTEPH in hemodynamics and VO 2 % of predicted (67.8 ± 18.7 vs. 66.0 ± 19.8, p < 0.05), but those with CTEPH had higher dyspnea, VD/VT (0.36 ± 0.09 vs. 0.23 ± 0.9, p < 0.001), VE/ VCO 2 (45.8 ± 7.1 vs. 39.3 ± 5.6, p < 0.001), and PA-aO 2 (19.9 ± 7.6 vs. 13.5 ± 7.6, p < 0.001) than PAH patients. Conclusions: At altitude, patients with PH present severe alterations in gas exchange during exercise. There were no differences in exercise capacity between PAH and CTEPH, but patients with CTEPH had more dyspnea and greater alterations in gas exchange during exercise. CPET made it possible to identify alterations related to the pathophysiology of CTEPH that could explain the functional class and dyspnea in these patients.

Approach to interstitial lung disease associated with systemic sclerosis-A survey to pulmonologists and rheumatologists in Colombia.

INTRODUCTION: Interstitial lung disease is a leading cause of mortality in patients with systemic sclerosis. Currently, there is a lack of consensus regarding screening, rescreening, diagnosis, and follow-up practices in interstitial lung disease associated with systemic sclerosis (SSc-ILD) in Colombia. METHODS: A structured survey focused on clinical practices in patients with SSc-ILD was conducted. Members of the Asociación Colombiana de Neumología y Cirugía de Tórax (Asoneumocito) and the Asociación Colombiana de Reumatología (Asoreuma) were invited to participate from March 2023 to May 2023. RESULTS: We surveyed 51 pulmonologists and 44 rheumatologists. Overall, 51.6% reported having access to multidisciplinary team discussion in ILD. Among the 95 participants, 78.9% would routinely perform a high-resolution computed tomography scan of the chest once a diagnosis of systemic sclerosis was established. This practice is more frequent among rheumatologists (84.1%) than among pulmonologists (74.5%). Approximately half of the participants would rescreen patients annually with computed tomography scan (56.8%) if baseline images were negative. Spirometry (81.1%), diffusing capacity of the lung for carbon monoxide (80.0%), and 6-min walk test (55.8%) were the most frequently performed tests upon diagnosis of systemic sclerosis. During follow-up, participants would consider repeating pulmonary function tests mostly every 6 months. CONCLUSIONS: Screening of SSc-ILD is high among pulmonologists and rheumatologists. Decision-making on diagnosis and follow-up is similar between specialties, but there are variations in their frequency and indications. Further research is needed to evaluate how to adapt recommendations for assessing SSc-ILD in different settings.

Risk factors for persistent tomographic abnormalities at 6 months of follow-up in a cohort of hospitalized patients with moderate and severe COVID-19 living at high altitude.

Introduction: After COVID-19, functional and tomographic lung alterations may occur, but there are no studies at high altitude where, due to lower barometric pressure, there are lower levels of arterial oxygen pressure and saturation in both normal subjects and patients with respiratory disease. In this study, we evaluated the computed tomographic (CT), clinical, and functional involvement at 3 and 6 months post-hospitalization in survivors with moderate-severe COVID-19, as well the risk factors associated with abnormal lung computed tomography (ALCT) at 6 months of follow-up. Materials and methods: Prospective cohort, after hospitalization for COVID-19, of patients older than 18 years residing at high altitude. Follow-up at 3 and 6 months with lung CT, spirometry, diffusing capacity of the lung for carbon monoxide (DLCO), six-minute walk test (6MWT), and oxygen saturation (SpO2). Comparisons between ALCT and normal lung computed tomography (NLCT) groups with X2 and Mann-Whitney U test, and paired test for changes between 3 and 6 months. A multivariate analysis was performed to evaluate the variables associated with ALCT at 6-month follow-up. Results: We included 158 patients, 22.2% hospitalized in intensive care unit (ICU), 92.4% with typical COVID CT scan (peripheral, bilateral, or multifocal ground glass, with or without consolidation or findings of organizing pneumonia), and median hospitalization of 7 days. At 6 months, 53 patients (33.5%) had ALCT. There were no differences between ALCT and NLCT groups in symptoms or comorbidities on admission. ALCT patients were older and more frequently men, smokers and hospitalized in ICU. At 3 months, ALCT patients had more frequently a reduced forced vital capacity (< 80%), and lower meters walked (6MWT) and SpO2. At 6 months, all patients improved lung function with no differences between groups, but there were more dyspnea and lower exercise SpO2 in ALCT group. The variables associated with ALCT at 6 months were age, sex, ICU stay, and typical CT scan. Conclusion: At 6-month follow-up, 33.5% of patients with moderate and severe COVID had ALCT. These patients had more dyspnea and lower SpO2 in exercise. Regardless of the persistence of tomographic abnormalities, lung function and 6MWT improved. We identified the variables associated with ALCT.

Impacto clínico de un grupo de discusión multidisciplinaria en el diagnóstico de fibrosis pulmonar idiopática en Colombia / Clinical impact of a multidisciplinary discussion group on the diagnosis of idiopathic pulmonary fibrosis in Colombia

Resumen Introducción: la fibrosis pulmonar idiopática (FPI) es una enfermedad pulmonar intersticial (EPID) de mal pronóstico, considerada huérfana en Colombia. Un diagnóstico correcto tiene implicaciones para el paciente y los costos de atención. Los grupos de discusión multidisciplinaria (GDM) se consideran el estándar de oro en el diagnóstico. No hay estudios previos en Colombia de la experiencia de un GDM. Objetivos: evaluar el impacto de un GDM en una institución de cuarto nivel en Bogotá en cambio de diagnóstico de pacientes con EPID y la concordancia entre el diagnóstico inicial y final de FPI. Material y métodos: pacientes con EPID evaluados entre 2015-2018 por el GDM conformado por neumólogos, radiólogo, patólogo y reumatólogos. Criterios ATS/ERS/JRS/ALAT de diagnóstico de FPI. Descripción del cambio en el diagnóstico y concordancia entre el diagnóstico inicial y del GDM en FPI. Resultados: de 165 pacientes con EPID se cambió el diagnóstico en 35.2%. En 77.3% pacientes con diagnóstico inicial de FPI y en 6.7% con diagnóstico inicial diferente a FPI el GDM confirmó FPI. Al descartar FPI, los principales diagnósticos fueron neumonitis de hipersensibilidad en fase crónica (29.4%) y neumonía intersticial no específica (23.5%). El índice kappa entre el diagnóstico inicial y final de FPI fue 0.71 (0.60-0.82). Conclusiones: el GDM en EPID tuvo un importante impacto clínico demostrado por un alto porcentaje de cambió del diagnóstico de remisión. Se descartó el diagnóstico inicial de FPI en un porcentaje significativo de pacientes y se ratificó en un grupo menor sin esta sospecha clínica inicial. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2017).

Abstract Introduction: idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease (ILD) with a poor prognosis, considered an orphan disease in Colombia. An accurate diagnosis has implications for the patient and healthcare costs. Multidisciplinary discussion groups (MDGs) are considered the gold standard for diagnosis. There are no prior studies in Colombia on the experience of an MDG. Objectives: to evaluate the impact of an MDG in a quaternary care institution in Bogotá on the change in the diagnosis of patients with ILD and the concordance between the initial and final diagnosis of IPF. Materials and methods: patents with ILD evaluated from 2015-2018 by the MDG made up of pulmonologists, a radiologist, a pathologist and rheumatologists. The ATS/ERS/JRS/ALAT diagnostic criteria for IPF. A description of changes in the diagnosis and the agreement between the initial diagnosis and the MDG diagnosis of IPF. Results: out of 165 patients with ILD, the diagnosis was changed in 32.5%. The MDG confirmed IPF in 77.3% of patients with an initial diagnosis of ILD and 6.7% of those with a different initial diagnosis. When IPF was ruled out, the main diagnoses were chronic hypersensitivity pneumonitis (24.8%) and nonspecific interstitial pneumonia (23.5%). The Kappa index between the initial and final IPF diagnoses was 0.71 (0.60-0.82). Conclusions: the MDG on ILD had a significant clinical impact evidenced by a high percentage of change in the referral diagnosis. The initial diagnosis of IPF was ruled out in a significant percentage of patients and confirmed in a smaller group which did not have this initial clinical suspicion. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2017).

Hypersensitivity Pneumonitis: Diagnostic and Therapeutic Challenges.

Hypersensitivity pneumonitis (HP) is one of the most common interstitial lung diseases (ILD), that presents unique challenges for a confident diagnosis and limited therapeutic options. The disease is triggered by exposure to a wide variety of inciting antigens in susceptible individuals which results in T-cell hyperactivation and bronchioloalveolar inflammation. However, the genetic risk and the pathogenic mechanisms remain incompletely elucidated. Revised diagnostic criteria have recently been proposed, recommending to classify the disease in fibrotic and non-fibrotic HP which has strong therapeutic and outcome consequences. Confident diagnosis depends on the presence of clinical features of ILD, identification of the antigen(s), typical images on high-resolution computed tomography (HRCT), characteristic histopathological features, and lymphocytosis in the bronchoalveolar lavage. However, identifying the source of antigen is usually challenging, and HRCT and histopathology are often heterogeneous and not typical, supporting the notion that diagnosis should include a multidisciplinary assessment. Antigen removal and treating the inflammatory process is crucial in the progression of the disease since chronic persistent inflammation seems to be one of the mechanisms leading to lung fibrotic remodeling. Fibrotic HP has a few therapeutic options but evidence of efficacy is still scanty. Deciphering the molecular pathobiology of HP will contribute to open new therapeutic avenues and will provide vital insights in the search for novel diagnostic and prognostic biomarkers.

Comorbidities of Patients With Idiopathic Pulmonary Fibrosis in Four Latin American Countries. Are There Differences by Country and Altitude?

Background: Comorbidities in idiopathic pulmonary fibrosis (IPF) affect quality of life, symptoms, disease progression and survival. It is unknown what are the comorbidities in patients with IPF in Latin America (LA) and if there are differences between countries. Our objective was to compare IPF comorbidities in four countries and analyze possible differences by altitude. Methods: Patients with IPF according 2012 ATS/ERS/JRS/ALAT guidelines, from two cities with an altitude of ≥2,250 m: Mexico City (Mexico) and Bogotá (Colombia) and from three at sea level: Buenos Aires (Argentina) and Lima and Trujillo (Peru). Comorbidities and pulmonary function tests were taken from clinical records. Possible pulmonary hypertension (PH) was defined by findings in the transthoracic echocardiogram of systolic pulmonary arterial pressure (sPAP) >36 mmHg or indirect signs of PH in the absence of other causes of PH. Emphysema as the concomitant finding of IPF criteria on chest tomography plus emphysema in the upper lobes. ANOVA or Kruskal Wallis and χ2-tests were used for comparison. Results: Two hundred and seventy-six patients were included, 50 from Argentina, 86 from Colombia, 91 from Mexico and 49 from Peru. There prevalence of PH was higher in Colombia and Mexico (p < 0.001), systemic arterial hypertension in Argentina (p < 0.015), gastro-esophageal reflux and dyslipidemia in Colombia and Argentina (p < 0.001) and diabetes mellitus in Mexico (p < 0.007). Other comorbidities were obesity (28.4%), coronary artery disease (15.2%) and emphysema (14.9%), with no differences between countries. There was more PH in the altitude cities than those at sea level (51.7 vs. 15.3%, p < 0.001). In patients from Bogotá and Mexico City, arterial oxygen pressure, saturation (p < 0.001) and carbon monoxide diffusing capacity (p = 0.004) were significantly lower than in cities at sea level. Conclusions: In this study with a significant number of patients, we were able to describe and compare the comorbidities of IPF in four LA countries, which contributes to the epidemiological data of this disease in the region. The main results were the differences in comorbidities between the countries and more PH in the subjects residing in the cities of higher altitude, a finding that should be validated in future studies.

Cardiovascular events related to the use of macrolides in an intensive care unit / Eventos cardiovasculares relacionados con el uso de macrólidos en una unidad de cuidado intensivo

Abstract Introduction and objectives: macrolides are widely used antibiotics for which a greater frequency of cardiovascular events related to increased arrhythmias has been reported. This study seeks to describe some cardiovascular complications of the use of macrolides in ICU patients. Materials and methods: this was a descriptive cross-sectional study which included adult patients admitted to the Medical Intensive Care Unit at the Fundación Cardioinfantil who received antibiotic treatment with clarithromycin in 2013 and 2015. Results: the collected sample was 38 patients. The median age was 64 years, and clarithromycin was most frequently used for treating community-acquired infections, with pneumonia being the most common diagnosis. The frequency of atrial fibrillation or flutter was 7.89%, and ventricular tachycardia 2.63%. The most frequently used concomitant medication was quetiapine at 28.95%. The main cause of death was respiratory failure. Conclusions: the frequency of arrhythmias was high in our study, although the most frequent cause of death was respiratory failure. (Acta Med Colomb 2020; 45. DOI:https://doi.org/10.36104/amc.2020.1336).

Resumen Introducción y objetivos: los macrólidos son antibióticos ampliamente utilizados con los cuales se ha reportado una mayor frecuencia de eventos cardiovasculares relacionados con aumento de arritmias. Mediante este estudio, se busca describir algunas complicaciones cardiovasculares con el uso de macrólidos en pacientes en UCI. Materiales y métodos: se realizó un estudio descriptivo de corte transversal en el que se incluyeron pacientes adultos que ingresaron a la unidad de cuidado intensivo médico de la Fundación Cardioinfantil y que recibieron tratamiento antibiótico con claritromicina durante los años 2013 y 2015. Resultados: la muestra recolectada fue de 38 pacientes, la mediana de edad fue de 64 años y la claritromicina se usó más frecuentemente en el tratamiento de infecciones adquiridas en la comunidad, siendo la neumonía el diagnóstico más común. La frecuencia de arritmias tipo fibrilación o flutter auricular fue de 7.89% y de taquicardia ventricular 2.63%. El medicamento concomitante más frecuentemente usado fue la quetiapina con 28.95%. La principal causa de muerte fue falla respiratoria. Conclusiones: la frecuencia de arritmias fue alta en nuestro, aunque la causa de muerte más frecuente fue falla respiratoria.(Acta Med Colomb 2020; 45. DOI:https://doi.org/10.36104/amc.2020.1336).