Adult-onset Williams-Campbell syndrome: Clinical presentations, diagnostic challenges, and treatment approaches.

Williams-Campbell syndrome (WCS), traditionally recognized in childhood, is a rare congenital disorder characterized by subsegmental bronchial cartilage deficiency, leading to bronchiectasis. However, its occurrence in adults presents unique diagnostic complexities. We present two cases: Case 1, a 53-year-old male with recurrent rhinosinusitis and COVID-19-associated lung cysts; Case 2, a 59-year-old cyclist with pulmonary bullae. Diagnostic evaluations included pulmonary function tests and imaging studies. Both cases underwent extensive diagnostic evaluations before WCS diagnosis. Management was focused on symptom alleviation and pneumococcal vaccination. Adult-onset WCS poses diagnostic challenges, often mimicking other respiratory conditions. Pathology confirmation is a gold standard for definitive diagnosis; however, in the case of WCS, the literature supports a diagnostic approach primarily based on clinical and radiological findings. Early recognition and tailored management strategies are essential to enhance patient outcomes.

Mexican Hispanics show significant improvement in lung function approximately 1 year after having severe COVID-19.

The long-term effects of COVID-19 on lung function are not understood, especially for periods extending beyond 1 year after infection. This observational, longitudinal study investigated lung function in Mexican Hispanics who experienced severe COVID-19, focusing on how the length of recovery affects lung function improvements. At a specialized COVID-19 follow-up clinic in Yucatan, Mexico, lung function and symptoms were assessed in patients who had recovered from severe COVID-19. We used z-scores, and Wilcoxon's signed rank test to analyse changes in lung function over time. Lung function was measured twice in 82 patients: the first and second measurements were taken a median of 94 and 362 days after COVID-19 diagnosis, respectively. Initially, 61% of patients exhibited at least one of several pulmonary function abnormalities (lower limit of normal = -1.645), which decreased to 22% of patients by 390 days post-recovery. Considering day-to-day variability in lung function, 68% of patients showed improvement by the final visit, while 30% had unchanged lung function from the initial assessment. Computed tomography (CT) scans revealed ground-glass opacities in 33% of patients. One year after infection, diffusing capacity of the lungs for carbon monoxide z-scores accounted for 30% of the variation in CT fibrosis scores. There was no significant correlation between the length of recovery and improvement in lung function based on z-scores. In conclusion, 22% of patients who recovered from severe COVID-19 continued to show at least one lung function abnormality 1 year after recovery, indicating a prolonged impact of COVID-19 on lung health.

Effect of vaccination on COVID-19 mortality during omicron wave among highly marginalized mexican population.

Background: Social determinants have played a role in COVID-19 outcomes and vaccination has improved these and impacted on inflammatory response, we therefore sought to investigate the association between vaccination and inflammatory response with COVID-19 mortality in a Mexican population with high marginalization during the Omicron wave. Methods: Prospective, longitudinal, single-center study in a setting of high marginalization conducted during the Omicron wave, from January to November 2022. Clinical and laboratory data were collected during admission and patients were followed until discharge or death. Patients were grouped according to outcome (survival and non-survival), and by complete (2 or more doses) and incomplete vaccination status for comparison. Results: 118 patients were included, 54% (64/118) male, with a median age 63 years and 86% (102/118) with self-reported comorbidities. Mortality was 42%. 58% (68/118) had complete vaccination. There was a 64% risk reduction for all-cause in-hospital mortality of having complete vaccination, hazard ratio 0.36, (95% CI 0.18-0.71, p = 0.004) in the proportional hazards Cox regression test. Survivor group arrived earlier to medical care and had higher SpO2 on admission, and for inflammatory response, had lower levels of Neutrophil-to-lymphocyte ratio, C-reactive protein, and D-dimer at admission. In the longitudinal measurement, only D-dimer showed significant differences between groups according to survival. Conclusion: In a highly marginalized Mexican population, complete vaccination has a protective effect against COVID-19 all-cause in-hospital mortality compared with incomplete or no vaccination. However, mortality in this population during the Omicron wave is high. Socio-economic inequalities may play an important role in COVID-19 outcomes.

Knowledge and perceptions regarding pulmonary rehabilitation amongst Ecuadorian physicians following COVID-19 outbreak.

Background: Pulmonary rehabilitation is already an established technique for patients with chronic respiratory disease, aimed at improving breathlessness, exercise capacity, health status, and well-being. The aim of this study was to assess the knowledge and perceptions about pulmonary rehabilitation post-COVID-19 infection among Ecuadorian physicians. Methods: We conducted a cross-sectional online survey-based study using a 27-item questionnaire to assess the knowledge about specific topics related to pulmonary rehabilitation. The sample comprised Ecuadorian physicians who were currently enrolled to an active medical practice that included care to COVID-19 patients. Descriptive statistics were applied for demographic variables of interest. A chi-square goodness of fit test was used to determine whether the observed frequencies of each of the answers per query were within or outside of the expected frequencies by chance. Results: In total, 295 participants answered the survey, out of which 57.3% were general practitioners. Most agreed that COVID-19 infected patients must be followed-up with some measurement of respiratory function (81.4%, p=0.000), but only 18.3% (n=54, p=0.000) were aware of specific guidelines related to rehabilitation. 93.6% (n=276, p=0.000) considered that pulmonary rehabilitation provides a benefit, of any kind, to patients with past COVID-19 infection. Conclusions: Most physicians considered pulmonary rehabilitation beneficial following COVID-19. However, there is uncertainty on how to adequately follow up patients, complementary tests, and specific guidelines outlining rehabilitative interventions.

Understanding the Gaps in the Reporting of COPD Exacerbations by Patients: A Review.

Exacerbations of chronic obstructive pulmonary disease (COPD) are associated with loss of lung function, poor quality of life, loss of exercise capacity, risk of serious cardiovascular events, hospitalization, and death. However, patients underreport exacerbations, and evidence suggests that unreported exacerbations have similar negative health implications for patients as those that are reported. Whilst there is guidance for physicians to identify patients who are at risk of exacerbations, they do not help patients recognise and report them. Newly developed tools, such as the COPD Exacerbation Recognition Tool (CERT) have been designed to achieve this objective. This review focuses on the underreporting of COPD exacerbations by patients, the factors associated with this, the consequences of underreporting, and potential solutions.

Small airway disease in post-acute COVID-19 syndrome, a non-conventional approach in three years follow-up of a patient with long COVID: a case report.

BACKGROUND: Small airways disease (SAD), a novel finding described in post-acute COVID-19 patients, should be suspected when respiratory symptoms continue, air trapping persists on expiratory CT scans, and imaging findings fail to improve despite objectively better conventional pulmonary function test (PFT) parameters. The forced oscillation technique (FOT) and Multiple breathing washout (MBW) are both very sensitive methods for detecting anomalies in the peripheral airways. CASE PRESENTATION: We discuss the case of a 60-year-old Hispanic patient who had severe COVID-19 pneumonia and developed dyspnea, fatigue, and limited daily activity a year later. The PFTs revealed restrictive lung disease, as seen by significant diffusing capacity of the lungs for carbon monoxide (DLCO) decrease, severe desaturation, and poor 6-min walk test (6MWT) performance. The patient was treated with lowering corticosteroids as well as pulmonary rehabilitation (PR). During the 24-month follow-up, the dyspnea and fatigue persisted. On PFTs, 6MWT performance and restricted pattern improved slightly, but MBW discovered significant ventilatory inhomogeneity. FOT revealed substantial peripheral airway obstructive abnormalities. On CT scans, air trapping and ground-glass opacities (GGO) improved somewhat. The patient used a bronchodilator twice a day and low-dose inhaled corticosteroids (160 µg of budesonide and 4.5 µg of formoterol fumarate dihydrate) for nine months. PR sessions were resuming. The restricting parameters were stabilized and the DLCO had normalized after 36 months, with a 6MWT performance of 87% but significant desaturation. The CT scan revealed traction bronchiectasis, low GGO, and persistent air trapping. Without normalization, FOT and MBW scores improved, indicating small airway disease. CONCLUSIONS: The necessity of integrating these tests when detecting SAD is emphasized in our paper. This article lays the foundation for future research into the best ways to manage and monitor SAD in post-acute COVID-19 patients.

[Small airway: from definition to treatment]. / Vía aérea pequeña: de la definición al tratamiento.

The small airway, present since the origins of humanity and described barely a century ago, has recently been discovered as the anatomical site where inflammation begins in some obstructive lung diseases, such as asthma and Chronic Obstructive Pulmonary Disease (COPD), per se. Small airway dysfuction was identified in up to 91% of asthmatic patients and in a large proportion of COPD patients. In subjects without pathology, small airway represent 98.8% (approximately 4500 ml) of the total lung volume, contributing only between 10-25% of the total lung resistance; however, in subjects with obstruction, it can represent up to 90% of the total resistance. Despite this, its morphological and functional characteristics allow its dysfunction to remain undetected by conventional diagnostic methods, such as spirometry. Hence the importance of this review, which offers an overview of the tools available to assess small airway dysfunction and the possible therapies that act in this silent zone.

La vía aérea pequeña, presente desde los orígenes de la humanidad y descrita hace apenas un siglo, se ha descubierto recientemente como el sitio anatómico donde inicia la inflamación provocada por algunas enfermedades pulmonares obstructivas: asma y enfermedad pulmonar obstructiva crónica (EPOC), per se. Se ha identificado disfunción de la vía aérea pequeña en el 91% de los pacientes asmáticos y en una gran proporción de quienes padecen EPOC. En los pacientes sin enfermedad, la vía aérea pequeña representa el 98.8% (4500 mL) del volumen pulmonar total, y solo aporta del 10 al 25% de la resistencia pulmonar total; sin embargo, en sujetos con obstrucción puede suponer el 90% de la resistencia total. A pesar de esto, sus características morfológicas y funcionales permiten que la disfunción pase inadvertida por métodos diagnósticos convencionales, por ejemplo la espirometría. Con base en lo anterior, el objetivo de este estudio fue revisar el panorama general de los métodos disponibles para evaluar la vía aérea pequeña y los posibles tratamientos asociados con esta zona silente.

Inflammation associated with lung function abnormalities in COVID-19 survivors.

BACKGROUND: Activation of inflammatory pathways promotes organ dysfunction in COVID-19. Currently, there are reports describing lung function abnormalities in COVID-19 survivors; however, the biological mechanisms remain unknown. The aim of this study was to analyze the association between serum biomarkers collected during and following hospitalization and pulmonary function in COVID-19 survivors. METHODS: Patients recovering from severe COVID-19 were prospectively evaluated. Serum biomarkers were analyzed from admission to hospital, peak during hospitalization, and at the time of discharge. Pulmonary function was measured approximately 6 weeks after discharge. RESULTS: 100 patients (63% male) were included (age 48 years, SD ± 14) with 85% having at least one comorbidity. Patients with a restrictive spirometry pattern (n = 46) had greater inflammatory biomarkers compared to those with normal spirometry (n = 54) including peak Neutrophil-to-Lymphocyte ratio (NLR) value [9.3 (10.1) vs. 6.5 (6.6), median (IQR), p = 0.027] and NLR at hospital discharge [4.6 (2.9) vs. 3.2 (2.9) p = 0.005] and baseline C-reactive protein value [164.0 (147.0) vs. 106.5 (139.0) mg/dL, p = 0.083). Patients with an abnormal diffusing capacity (n = 35) had increased peak NLR [8.9 (5.9) vs. 5.6 (5.7) mg/L, p = 0.029]; baseline NLR [10.0 (19.0) vs. 4.0 (3.0) pg/ml, p = 0.002] and peak Troponin-T [10.0 (20.0) vs. 5.0 (5.0) pg/ml, p = 0.011] compared to patients with normal diffusing capacity (n = 42). Multivariable linear regression analysis identified predictors of restrictive spirometry and low diffusing capacity, but only accounted for a low degree of variance in pulmonary function outcome. CONCLUSION: Overexpression of inflammatory biomarkers is associated with subsequent lung function abnormalities in patients recovered from severe COVID-19.

Modeling mortality risk in patients with severe COVID-19 from Mexico.

Background: Severe acute respiratory syndrome caused by a coronavirus (SARS-CoV-2) is responsible for the COVID-19 disease pandemic that began in Wuhan, China, in December 2019. Since then, nearly seven million deaths have occurred worldwide due to COVID-19. Mexicans are especially vulnerable to the COVID-19 pandemic as Mexico has nearly the worst observed case-fatality ratio (4.5%). As Mexican Latinos represent a vulnerable population, this study aimed to determine significant predictors of mortality in Mexicans with COVID-19 who were admitted to a large acute care hospital. Methods: In this observational, cross-sectional study, 247 adult patients participated. These patients were consecutively admitted to a third-level referral center in Yucatan, Mexico, from March 1st, 2020, to August 31st, 2020, with COVID-19-related symptoms. Lasso logistic and binary logistic regression were used to identify clinical predictors of death. Results: After a hospital stay of about eight days, 146 (60%) patients were discharged; however, 40% died by the twelfth day (on average) after hospital admission. Out of 22 possible predictors, five crucial predictors of death were found, ranked by the most to least important: (1) needing to be placed on a mechanical ventilator, (2) reduced platelet concentration at admission, (3) increased derived neutrophil to lymphocyte ratio, (4) increased age, and (5) reduced pulse oximetry saturation at admission. The model revealed that these five variables shared ~83% variance in outcome. Conclusion: Of the 247 Mexican Latinos patients admitted with COVID-19, 40% died 12 days after admission. The patients' need for mechanical ventilation (due to severe illness) was the most important predictor of mortality, as it increased the odds of death by nearly 200-fold.

Impacto de las exacerbaciones en la enfermedad pulmonar obstructiva crónica / Impact of Exacerbations on Chronic Obstructive Pulmonary Disease

La enfermedad pulmonar obstructiva crónica (EPOC) es la tercera causa de muerte en todo el mundo. Sin embargo, ante la falta de herramientas diagnósticas precisas en el primer nivel de atención médica, como la espirometría, es difícil determinar la prevalen-cia real de la EPOC.Por otro lado, la falta de una definición clara y precisa de las exacerbaciones de la EPOC hace que se subestime su impacto en la salud pública; habitualmente, los pacien-tes con EPOC que cursan una exacerbación retrasan la búsqueda de atención médica inmediata porque se acostumbran al deterioro asociado a la enfermedad o lo confun-den con cambios por la edad avanzada. Esto puede provocar un aumento de la mor-bilidad y la mortalidad, asimismo, mayor utilización de los recursos sanitarios y mayor carga económica. Por lo tanto, es importante sensibilizar sobre la importancia del diagnóstico temprano y el tratamiento adecuado de las exacerbaciones de la EPOC, del mismo modo que el mayor conocimiento público de los síntomas, las causas y los factores de riesgo de la EPOC. Con ello, se podrán aplicar estrategias de prevención, diagnóstico y tratamiento más eficaces que mejoren la calidad de vida de los pacientes y disminuyan la carga de la enfermedad para la sociedad.Esta revisión ofrece un análisis crítico de la definición más reciente y esboza las impli-caciones del comportamiento de las exacerbaciones, su impacto en los distintos ám-bitos del sistema sanitario, así como en las diferentes esferas de la vida de los pacien-tes con EPOC. (AU)

Chronic Obstructive Pulmonary Disease (COPD) is a common disease and the third leading cause of death worldwide. However, due to the lack of accurate diagnostic tools at the first level of care, such as spirometry, the true prevalence of COPD is difficult to determine.In addition, the lack of a clear definition of COPD exacerbations means that its pub-lic health impact is underestimated. Patients with COPD often do not seek immediate medical attention because they become used to the deterioration associated with the disease. This can lead to increased patient morbidity and mortality, as well as increased utilization of healthcare resources and higher economic costs. Therefore, it is important to promote greater awareness of the importance of early di-agnosis and proper management of COPD exacerbations, as well as increased public awareness of COPD symptoms, etiologic agents, and risk factors.By better understanding COPD exacerbations, more effective prevention, diagnosis and treatment strategies can be implemented to improve the quality of life of patients and reduce the burden of the disease on society.This review aims to provide a critical analysis of the most recent definition and to out-line the implications of the behavior of COPD exacerbations and their impact on the dif-ferent settings of the health care system, as well as on the different spheres of patients' lives. (AU)

Effect of Altitude on Respiratory Functional Status in COVID-19 Survivors: Results from a Latin American Cohort-FIRCOV.

Laura Gochicoa-Rangel, Santiago C. Arce, Carlos Aguirre-Franco, Wilmer Madrid-Mejía, Mónica Gutiérrez-Clavería, Lorena Noriega-Aguirre, Patricia Schonffeldt-Guerrero, Agustín Acuña-Izcaray, Arturo Cortés-Telles, Luisa Martínez-Valdeavellano, Federico Isaac Hernández-Rocha, Omar Ceballos-Zúñiga, Rodrigo Del Rio Hidalgo, Sonia Sánchez, Erika Meneses-Tamayo, and Iván Chérrez-Ojeda; and on Behalf of the Respiratory Physiology Project in COVID-19 (FIRCOV). Effect of altitude on respiratory functional status in COVID-19 survivors: results from a Latin American Cohort-FIRCOV. High Alt Med Biol 24:37-48, 2023. Persistent symptoms and lung function abnormalities are common in COVID-19 survivors. Objectives: To determine the effect of altitude and other independent variables on respiratory function in COVID-19 survivors. Methods: Analytical, observational, cross-sectional cohort study done at 13 medical centers in Latin America located at different altitudes above sea level. COVID-19 survivors were invited to perform pulmonary function tests at least 3 weeks after diagnosis. Results: 1,368 participants (59% male) had mild (20%), moderate (59%), and severe (21%) disease. Restriction by spirometry was noted in 32%; diffusing capacity of the lung for carbon monoxide (DLCO) was low in 43.7%; and 22.2% walked less meters during the 6-minute walk test (6-MWT). In multiple linear regression models, higher altitude was associated with better spirometry, DLCO and 6-MWT, but lower oxygen saturation at rest and during exercise. Men were 3 times more likely to have restriction and 5.7 times more likely to have a low DLCO. Those who had required mechanical ventilation had lower DLCO and walked less during the 6-MWT. Conclusions: Men were more likely to have lower lung function than women, even after correcting for disease severity and other factors. Patients living at a higher altitude were more likely to have better spirometric patterns and walked farther but had lower DLCO and oxygen saturation.

Dynamic inflammatory response among routine laboratory biomarkers and their predictive ability for mortality in patients with severe COVID-19.

Background: The severity of coronavirus disease 2019 (COVID-19) is related to several factors, including age, sex, and comorbidities (obesity, type 2 diabetes, and hypertension). However, systemic inflammation plays a fundamental role in COVID-19 pathophysiology. Several studies have described this association employing specific biomarkers that are not routinely used in clinical practice. On the other hand, very few reports in the literature focused on the analysis of the routine laboratory biomarkers to predict the outcome of severe COVID-19 patients. Objective: We aimed to analyze the dynamic inflammatory response using routine laboratory biomarkers to predict in-hospital mortality in Mexican patients with severe COVID-19. Methods: This is a cohort study including patients with severe COVID-19. Demographic characteristics were retrieved from medical charts and biochemical parameters were measured at hospital admission and subsequently on days 3, 5, 7, 10, 14, and 21 during the hospital stay; measurements were stopped when patients were discharged from the hospital (alive or death). Results: A total of 250 patients were included in the study, 40.8% of patients died. The analyzed routine laboratory parameters, such as serum levels of neutrophil-to-lymphocyte ratio, C-reactive protein, and D-dimer remained elevated in hospitalized patients who did not survive, whereas eosinophil and platelets were maintained at lower levels. In the multivariate analysis, leukocytes, and neutrophils were the best biomarkers for predicting mortality risk and were independent of age, gender, or comorbidities. Conclusion: Our results support the use of routine laboratory biomarkers as predictors of mortality in Mexican hospitalized patients with severe COVID-19.

Challenges in the Management of Post-COVID-19 Pulmonary Fibrosis for the Latin American Population.

This commentary aims to highlight some of the major issues (with possible solutions) that the Latin American region is currently dealing with in managing post-COVID-19 pulmonary fibrosis. Overall, there is little evidence for successful long-term COVID-19 follow-up treatment. The lack of knowledge regarding proper treatment is exacerbated in Latin America by a general lack of resources devoted to healthcare, and a lack of availability and access to multidisciplinary teams. The discussion suggests that better infrastructure (primarily multicenter cohorts of COVID-19 survivors) and well-designed studies are required to develop scientific knowledge to improve treatment for the increasing prevalence of pulmonary fibrosis in Latin America.

Clinical predictors of lung function in patients recovering from mild COVID-19.

BACKGROUND: Few studies have assessed lung function in Hispanic subjects recovering from mild COVID-19. Therefore, we examined the prevalence of impaired pulmonary diffusing capacity for carbon monoxide (DLCO) as defined by values below the lower limit of normal (< LLN, < 5th percentile) or less than 80% of predicted in Hispanics recovering from mild COVID-19. We also examined the prevalence of a restrictive spirometric pattern as defined by the ratio of forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) being ≥ LLN with the FVC being < LLN. Finally, we evaluated previous studies to find factors correlated to impaired DLCO post-COVID-19. METHODS: In this observational study, adult patients (n = 146) with mild COVID-19 were recruited from a long-term follow-up COVID-19 clinic in Yucatan, Mexico, between March and August 2021. Spirometry, DLCO, and self-reported signs/symptoms were recorded 34 ± 4 days after diagnosis. RESULTS: At post-evaluation, 20% and 30% of patients recovering from COVID-19 were classified as having a restrictive spirometric pattern and impaired DLCO, respectively; 13% had both. The most prevalent reported symptoms were fatigue (73%), a persistent cough (43%), shortness of breath (42%) and a blocked/runny nose (36%). Increased age and a restrictive spirometric pattern increased the probability of having an impaired DLCO while having a blocked nose and excessive sweating decreased the likelihood. The proportion of patients with previous mild COVID-19 and impaired DLCO increased by 13% when the definition of impaired DLCO was < 80% predicted instead of below the LLN. When comparing previous studies, having severe COVID-19 increased the proportion of those with impaired DLCO by 21% compared to those with mild COVID-19. CONCLUSIONS: One-third of patients with mild COVID-19 have impaired DLCO thirty-four days post-diagnosis. The criteria that define impaired DLCO and the severity of COVID-19 disease affects the proportion of those with impaired DLCO at follow-up. One-fifth of patients have a restrictive spirometric pattern.

Cystatin C is a marker for acute kidney injury, but not for mortality among COVID-19 patients in Mexico.

BACKGROUND: Patients infected with SARS-CoV-2 can develop acute kidney injury (AKI), associated with adverse clinical outcomes. In Mexico, an AKI incidence of 60.7% was reported in patients with COVID-19. Serum cystatin C is a well-known marker for AKI. It has been postulated as a marker for mortality in Chinese patients with COVID-19. Information regarding levels of cystatin C in COVID-19-infected patients is nonexistent among Mexican or Latin American populations. AIM: This work aimed to assess the level of cystatin C as an indicator of AKI and mortality among COVID-19 patients from Mexico. METHODS: A cross-sectional study among 38 adults was performed in the Regional High Specialty Hospital of the Yucatan Peninsula in Merida, Yucatan, Mexico. Baseline characteristics and clinical and biomechanical parameters were collected, and serum levels of cystatin C were measured by ELISA. RESULTS: A total of 71% (27 patients) with COVID-19 developed AKI; 78% were men, and 22% were women. In addition, 60% of individuals (16 men; 7 women) died due to COVID-19 complications. Serum levels of cystatin C were higher in those individuals who developed AKI (p = 0.001). A logistic regression model indicated that individuals with serum levels of cystatin C above 0.84 ng/mL had a 23-fold increased risk of developing AKI (OR, 23.7, 95% CI, 2.59-217.00, p = 0.005). However, increased cystatin C was not independently associated with mortality in the Mexican population (HR, 1.01, 95% CI, 0.66-1.56, p = 0.959). CONCLUSION: The results suggest that serum levels of cystatin C indicate AKI in COVID-19 patients. Although we recommend caution when using serum cystatin C levels as an indicator of mortality among the Mexican population, it is essential to note that cystatin C elevates earlier than creatinine, which is an advantage for timely clinical interventions.

Pneumomediastinum Associated with COVID-19: A Case Series.

Coronavirus disease 2019 (COVID-19), caused by the new coronavirus SARSCoV-2, is an infectious disease that has caused an increase in hospitalizations for pneumonia; the spectrum of clinical presentation is variable. One such presentation, pneumomediastinum (PM), is defined as the presence of air or some other gas in the mediastinum. It is a rare condition, usually benign and self-limited; it has been seen in patients with COVID-19. Although most cases are, as explained above, self limited and in addition, can be managed conservatively, close monitoring is recommended, as PM can cause life-threatening hemodynamic and respiratory disturbances. We present a case series of 4 patients with SARS CoV-2 infection, in whom PM was found, and who were admitted to the Regional Hospital of High Specialty of the Yucatan Peninsula during the period of May 2020 through August 2020.

Humoral immune response in healthcare workers after two doses of a BNT162b2 mRNA vaccine in Yucatan, Mexico.

The antibody response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as well as the host immune response after vaccination and viral infection have shown to be highly heterogeneous. This is a case series study analysing humoral immune response and vaccination side effects after two doses of a BNT162b2 mRNA among healthcare workers (HCWs) in Mexico. All participants were scheduled for their two doses of mRNA BNT162b2 vaccine and provided information through a questionnaire: demographic characteristics, antibody serum titres and vaccination-related side effects. Blood samples were obtained for serology testing after the first and second doses of vaccine. No serious adverse effects due to vaccination were reported; nonetheless, non-medical HCWs reported more side effects after the second dose. The previous infection with SARS-CoV-2 boosted immune response after receiving the first vaccination (roughly 30 times higher than those without previous infection); nonetheless, after the second dose, the immune response did not show a higher titre as might be expected.

Cystatin C is a marker for acute kidney injury, but not for mortality among COVID-19 patients in Mexico

ABSTRACT Background: Patients infected with SARS-CoV-2 can develop acute kidney injury (AKI), associated with adverse clinical outcomes. In Mexico, an AKI incidence of 60.7% was reported in patients with COVID-19. Serum cystatin C is a well-known marker for AKI. It has been postulated as a marker for mortality in Chinese patients with COVID-19. Information regarding levels of cystatin C in COVID-19-infected patients is nonexistent among Mexican or Latin American populations. Aim: This work aimed to assess the level of cystatin C as an indicator of AKI and mortality among COVID-19 patients from Mexico. Methods: A cross-sectional study among 38 adults was performed in the Regional High Specialty Hospital of the Yucatan Peninsula in Merida, Yucatan, Mexico. Baseline characteristics and clinical and biomechanical parameters were collected, and serum levels of cystatin C were measured by ELISA. Results: A total of 71% (27 patients) with COVID-19 developed AKI; 78% were men, and 22% were women. In addition, 60% of individuals (16 men; 7 women) died due to COVID-19 complications. Serum levels of cystatin C were higher in those individuals who developed AKI (p = 0.001). A logistic regression model indicated that individuals with serum levels of cystatin C above 0.84 ng/mL had a 23-fold increased risk of developing AKI (OR, 23.7, 95% CI, 2.59-217.00, p = 0.005). However, increased cystatin C was not independently associated with mortality in the Mexican population (HR, 1.01, 95% CI, 0.66-1.56, p = 0.959). Conclusion: The results suggest that serum levels of cystatin C indicate AKI in COVID-19 patients. Although we recommend caution when using serum cystatin C levels as an indicator of mortality among the Mexican population, it is essential to note that cystatin C elevates earlier than creatinine, which is an advantage for timely clinical interventions.

Secondary spontaneous pneumothorax: a time to re-evaluate management.

Spontaneous pneumothorax (SP) is defined as the presence of air in the pleural cavity and remains a significant health problem. Secondary SP (SSP) is associated with underlying lung diseases, such as cystic fibrosis, chronic obstructive pulmonary disease (COPD), and interstitial lung disease (ILD), and is associated with poor outcomes. The current guidelines in the management of SSP have not been updated since the last decade; therefore, new protocols focused on the management of SSP should be evaluated. We present two cases of patients admitted with SSP who were treated conservatively due to haemodynamic stability. In both cases, the pneumothoraces resolved without further complications.