Renal transplant waiting list mortality in COVID era: is it advisable to halt transplant activity?

INTRODUCTION: Kidney transplantation is the treatment of choice for end-stage renal disease (ESRD). Since March 2020, transplant activity in Mexico has been affected due to the COVID-19 pandemic. OBJECTIVE: The aim of the study was to determine the impact on mortality of patients on the waiting list (WL) for cadaveric donor kidney transplantation in a referral hospital in Yucatán, due to suspension of activities due to the pandemic. MATERIAL AND METHODS: Patients over 18 years of age on the waiting list for kidney transplantation at this hospital. In the event of a patient's death, the cause was investigated, especially if it was associated with COVID-19. A two-tailed p ≤ 0.05 was considered significant in all analyzes. RESULTS: The odds ratio (OR) of death from COVID-19 in a patient with ESRD in the WL in 2020 was OR = 5.04 (95% CI: 1.65-7.14, p = 0.023). The OR of dying with ESRD in the WL with a delay in the follow-up visits was OR = 6.59 (95% CI: 2.7-16.28, p = 0.008). CONCLUSION: The probability of death of a patient with ESRD with delayed follow-up visits and transplant retention is statistically higher than the probability of death from COVID-19.

INTRODUCCIÓN: El trasplante renal es el tratamiento de elección de la enfermedad renal en etapa terminal (ERT). Desde marzo de 2020, la actividad de trasplantes en México se ha visto afectada debido a la pandemia de COVID-19. OBJETIVO: Determinar el impacto en la mortalidad de pacientes en lista de espera (LE) para trasplante renal de donante cadavérico en un hospital de referencia en Yucatán, por suspensión de actividades debido a la pandemia. MATERIAL Y MÉTODOS: Pacientes > 18 años en LE para trasplante renal en este hospital. En caso de muerte de un paciente, se investigó la causa, especialmente si estaba asociada a COVID-19. Un valor de p de dos colas ≤ 0.05 se consideró significativo en todos los análisis. RESULTADOS: La razón de probabilidad de muerte por COVID-19 en un paciente con ERT en la LE en 2020 fue OR = 5.04 (IC 95%: 1.65-7.14, p = 0.023). La razón de probabilidad de morir con ERT en la LE con retraso en las consultas de seguimiento fue de OR = 6.59 (IC 95%: 2.7-16.28, p = 0.008). CONCLUSIÓN: La probabilidad de muerte de un paciente con ERT en la LE con retraso en las consultas de seguimiento y retención del trasplante es estadísticamente más alta que la probabilidad de muerte por COVID-19.

Parche de sangre cervical para tratamiento de síndrome de hipotensión/ hipovolumen de líquido cefalorraquídeo espontáneo. Reporte de un caso / Cervical blood patch for the treatment of spontaneous cerebrospinal fluid hypotension/hypovolume syndrome. A case report

Presentamos el tratamiento eficaz de una filtración espontánea de líquido cefalorraquídeo (LCR) asociada a un síndrome de hipoten-sión/hipovolumen de LCR a nivel cervical alto, caracterizado por delirio y hematomas subdurales secundarios, refractarios al drenaje quirúrgico, que se resolvió con dos parches de sangre epidurales cervicales consecutivos.

We present the case of a cerebrospinal fluid (CSF) hypotension/hypovolume syndrome due to a spontaneous CSF fistula at the upper cervical level characterized by loss of consciousness and bilateral subdural hematomas refractory to two drainage surgeries that resolved with two consecutive blood patches on the leak site.

Accuracy of a reference-free Monte Carlo approach for SEM-EDS thickness assessment of TiN coatings onto diverse substrates.

Energy dispersive spectroscopy (EDS) experiments were carried out in the scanning electron microscope (SEM) on top of either stainless steel (SS), silicon or glass substrates covered with TiN nitride coatings. The nominal coating thicknesses were 0.43, 1.1, 2.1 and 3.0 µm. From the EDS spectra obtained, the ratio between the strongest peak coming from the substrate and the Tik peak, from the coating, was assessed at an increasing microscope accelerating voltage (V0) between 10 and 30 kV. This ratio is afterward called Intensity-ratio (IR). A methodology was developed for assessing the coating thickness from the experimental IR and the V0 by using Monte Carlo simulations of the dispersion of electrons inside the covered samples and the concomitant emission of characteristic X-ray photons. Three freeware Monte Carlo graphical user interfaces were used, and the predicted thicknesses were compared between them, namely Casino, MC-Xray and DTSA. At fixed V0, numerical simulations predict a mono-valued and smooth relationship between IR and coating thickness. Monte Carlo predictions on the coating thickness were compared with reference thicknesses independently assessed by cross-sectional micrographs obtained in the SEM. Absolute value of percentage discrepancy between the predicted and the reference thicknesses was lower than 30 %, wherein the lower the V0, the less accurate the predicted thickness. In general, none of the three pieces of software compared outperformed the others, although predicted thicknesses significantly varied between them. For V0 higher than 20 kV, 90 % of predicted thicknesses deviated less than 15 % from the reference value. Predicted thicknesses for TiN coatings onto Si substrates presented the largest discrepancy regarding reference values.

Risk of a syndemic between COVID-19 and dengue fever in southern Mexico.

A syndemic is the convergence of two or more diseases in the same space and time. In Mexico, the dengue epidemic is active and predominates in areas of the Pacific and the Gulf of Mexico; in turn, the COVID-19 epidemic severely affects the same areas as dengue fever. Given that both these diseases share many clinical manifestations, in areas where tropical diseases are endemic, it is important to make careful evaluations of the patient who consults for fever in order to establish a timely diagnosis. Laboratory diagnostic tests are necessary to take the pertinent measures for each patient. In Mexico, the risk of a syndemic between COVID-19 and dengue fever is high, and thus it that can collapse health systems. The states of southeastern Mexico and the Pacific region require special attention, since they have geographic, environmental and climatic conditions that favor the rapid spread of dengue and COVID-19. Simultaneous infection will worsen the epidemiological situation, and complicate the diagnosis, control and treatment of both diseases.

Una sindemia es la convergencia de dos o más enfermedades en un mismo espacio y tiempo. En México, la epidemia de dengue está activa y predomina en zonas del Pacífico y Golfo de México; por su parte, la epidemia de COVID-19 afecta severamente las mismas zonas que el dengue. Dado que estas enfermedades comparten numerosas manifestaciones clínicas, en zonas endémicas de enfermedades tropicales es importante la evaluación minuciosa del paciente que consulta por fiebre, para establecer oportunamente un diagnóstico correcto. Las pruebas de laboratorio son necesarias para llevar a cabo las medidas pertinentes en cada paciente. En México, el riesgo de sindemia de COVID-19 y dengue es alto, por lo que puede colapsar los sistemas de salud. Los estados del sureste y los colindantes con el Pacífico requieren especial atención ya que presentan condiciones geográficas, ambientales y climáticas que favorecen la rápida propagación del dengue y COVID-19. La infección simultánea empeorará la situación epidemiológica, complicará el diagnóstico, control y tratamiento de ambas enfermedades.

Riesgo de sindemia de COVID-19 y fiebre del dengue en el sur de México / Risk of a syndemic between COVID-19 and dengue fever in southern Mexico

Resumen Una sindemia es la convergencia de dos o más enfermedades en un mismo espacio y tiempo. En México, la epidemia de dengue está activa y predomina en zonas del Pacífico y Golfo de México; por su parte, la epidemia de COVID-19 afecta severamente las mismas zonas que el dengue. Dado que estas enfermedades comparten numerosas manifestaciones clínicas, en zonas endémicas de enfermedades tropicales es importante la evaluación minuciosa del paciente que consulta por fiebre, para establecer oportunamente un diagnóstico correcto. Las pruebas de laboratorio son necesarias para llevar a cabo las medidas pertinentes en cada paciente. En México, el riesgo de sindemia de COVID-19 y dengue es alto, por lo que puede colapsar los sistemas de salud. Los estados del sureste y los colindantes con el Pacífico requieren especial atención ya que presentan condiciones geográficas, ambientales y climáticas que favorecen la rápida propagación del dengue y COVID-19. La infección simultánea empeorará la situación epidemiológica, complicará el diagnóstico, control y tratamiento de ambas enfermedades.

Abstract A syndemic is the convergence of two or more diseases in the same space and time. In Mexico, the dengue epidemic is active and predominates in areas of the Pacific and the Gulf of Mexico; in turn, the COVID-19 epidemic severely affects the same areas as dengue fever. Given that both these diseases share many clinical manifestations, in areas where tropical diseases are endemic, it is important to make careful evaluations of the patient who consults for fever in order to establish a timely diagnosis. Laboratory diagnostic tests are necessary to take the pertinent measures for each patient. In Mexico, the risk of a syndemic between COVID-19 and dengue fever is high, and thus it that can collapse health systems. The states of southeastern Mexico and the Pacific region require special attention, since they have geographic, environmental and climatic conditions that favor the rapid spread of dengue and COVID-19. Simultaneous infection will worsen the epidemiological situation, and complicate the diagnosis, control and treatment of both diseases.

Social cognition in Multiple Sclerosis is associated to changes in brain connectivity: A resting-state fMRI study.

BACKGROUND: Multiple Sclerosis produces changes in the functional connectivity of the brain. Resting-State fMRI is a useful tool for the study of functional changes in the human brain, and its metrics can be related to clinical findings involved in clinical decline. Social cognition has focused increasing interest because patients are exposed to experiencing social disorganization during the progression of the disease. fMRI has proved to be a useful tool for studying brain connectivity and its relation with social cognition both in resting-state and during socio-cognitive tasks. OBJECTIVE: to identify functional changes during rest in Relapsing-Remitting Multiple Sclerosis patients and look for a correlation with social cognition. METHODS: 45 patients with Relapsing-Remitting Multiple Sclerosis and 47 control subjects were recruited to perform a neuropsychological evaluation of the social cognition performance and to acquire resting-state fMRI. RESULTS: Patients exhibited lower performance in social cognition tasks, mostly related to face emotion recognition. Decreased functional connectivity in patients is seen concerning the right anterior insula, middle frontal, and occipital regions while increased connectivity is mostly related to the occipital and visual areas. The connectivity of the fusiform cortex and the amygdala is related to the performance in emotion recognition and Theory of Mind tasks respectively. CONCLUSION: Social cognition compromise was found in this sample. Functional connectivity changes during rest were detected and correlated with social cognition changes in patients.

Imágenes de resonancia magnética funcional en el estudio de la esclerosis múltiple / Functional magnetic resonance imaging in the study of multiple sclerosis

Introducción. La esclerosis múltiple (EM), una enfermedad neuroinflamatoria y desmielinizante, modifica la conectividad normal entre las diferentes regiones del cerebro involucradas en funciones específicas. La resonancia magnética funcional (RMf), basada en cambios locales en el nivel de oxígeno como respuesta al aumento de la actividad neuronal, proporciona un enfoque a la conectividad neuronal y la dinámica cerebral que ofrece una visión general de la disfunción visual, motora y cognitiva y sus mecanismos. Desarrollo. Se realizó una búsqueda avanzada en PubMed considerando los términos "fMRI", "visual", "motor", "cognitive" y "multiple sclerosis" incluidos en el título y el resumen. La búsqueda se centró en artículos originales disponibles en inglés, con énfasis en los útiles para comprender los cambios funcionales en la EM. Numerosos estudios han utilizado la RMf como una herramienta complementaria en el estudio de la EM y las alteraciones clínicamente relevantes de la afectación visual, motora y cognitiva. Desde las primeras etapas de la EM, la actividad local y la dinámica neural global parecen estar afectadas. Incluso cuando el desempeño funcional aún se conserva, surge un reclutamiento diferente de los recursos neuronales como respuesta compensatoria a la desconexión observada en la enfermedad. Conclusiones. Los principales hallazgos de la RMf aplicada a la EM están fuertemente relacionados con la naturaleza desmielinizante de la enfermedad y proporcionan una visión adecuada de los mecanismos subyacentes a las alteraciones funcionales. La RMf también parece ser útil para estudiar la evolución de la enfermedad y la respuesta al tratamiento en la EM y otros trastornos

Introduction. Multiple sclerosis (MS), a neuroinflammatory and demyelinating disease, modifies the normal connectivity among different brain regions involved in specific functions. Functional magnetic resonance imaging (fMRI), based on local changes in oxygen level as a response to the increase in neural activity, provides an approach to neural connectivity and brain dynamics which give us an overview on visual, motor and cognitive dysfunction and their mechanisms. Development. An advanced search was performed using PubMed. Terms 'fMRI', 'visual', 'motor', 'cognitive' and 'multiple sclerosis' included in title and abstract were considered. We focus on original articles available in English. Articles were included based on their abstracts, looking for those potentially useful for understanding functional changes in MS. An important amount of studies have used fMRI as a complementary tool in the study of MS and clinically relevant alterations compromising visual, motor and cognitive domains. Since the earliest stages of the disease, local activity, and global neural dynamics appear to be compromised. Even when functional performance is still preserved, a different recruitment of neural resources arises as a compensatory response to disconnection observed in the disease. Conclusions. The main findings of fMRI applied to MS are strongly related to the demyelinating nature of the disease and provide an adequate insight into the mechanisms that underlie functional alterations reported in this disease. fMRI also appears to be useful for studying disease evolution and response to treatment in MS and other disorders

The role of the Cys23Ser (rs6318) polymorphism of the HTR2C gene in suicidal behavior: systematic review and meta-analysis.

The polymorphisms of the serotonin receptor 2C (HTR2C) gene have been proposed to influence suicidal behavior. The aim of our study was to explore the role of the HTR2C gene variant Cys23Ser (rs6318) in the pathogenesis of suicidal behavior through a systematic review and meta-analysis. The search was performed using EBSCO and PubMed databases. To be included in the analysis, the studies had to evaluate suicidal behavior (attempted, ideation, or completed suicide). The results of the meta-analysis were expressed as odds ratios (ORs). Because HTR2C lies on chromosome X, pooled ORs were calculated, respectively, for each of the models used, namely: allelic, homozygous, dominant, and recessive for the female group and allelic for the male group. The meta-analysis comprised 3867 individuals, including 1668 cases and 2199 controls. The HTR2C Cys23Ser (rs6318) polymorphism did not show a significant association with suicidal behavior either in women (OR: 0.75; 95% confidence interval: 0.55-1.00) or in men (OR: 0.89; 95% confidence interval: 0.64-1.23). Similarly, nonsignificant associations were observed for all of the genetic models used in any of the populations/subgroups studied. Our findings suggest that the rs6318 (Cys23Ser) polymorphism is not associated with suicidal behavior. However, because of the study limitations, we suggest more researches should be performed, increasing the sample sizes and statistical power, to determine the association between the rs6318 variant and suicidal behavior.

Comprehensive data visualization for high resolution endovascular carotid arterial wall imaging.

Carotid angioplasty and stenting is a minimally invasive endovascular procedure that may benefit from in vivo high resolution imaging for monitoring the physical placement of the stent and potential complications. The purpose of this pilot study was to evaluate the ability of optical coherence tomography to construct high resolution 2D and 3D images of stenting in porcine carotid artery. Four Yorkshire pigs were anaesthetized and catheterized. A state-of-the-art optical coherence tomography (OCT) system and an automated injector were used to obtain both healthy and stented porcine carotid artery images. Data obtained were then processed for visualization. The state-of-the-art OCT system was able to capture high resolution images of both healthy and stented carotid arteries. High quality 3D images of healthy and stented carotid arteries were constructed, clearly depicting vessel wall morphological features, stent apposition and thrombus formation over the inserted stent. The results demonstrate that OCT can be used to generate high quality 3D images of carotid arterial stents for accurate diagnosis of stent apposition and complications under appropriate imaging conditions.

Carotid artery angioplasty and stenting for patients less than 70 years-of-age.

BACKGROUND: Recent studies have suggested that carotid artery angioplasty and stenting (CAS) is a safe alternative to carotid endarterectomy (CEA) in average risk patients <70 years of age. We examined a consecutive series of patients who underwent CAS in order to determine the influence of patient age on outcome. METHODS: A retrospective, longitudinal cohort study of consecutive patients who underwent CAS at St. Michael's Hospital, Canada between January 2001 and November 2010 was performed. The outcome measures were 30-day stroke and 30-day composite death, stroke and acute myocardial infarction (MI). Patients were stratified based on age <70 and ≥ 70 years. RESULTS: One hundred and fifty-nine patients underwent 165 CAS procedures. The 30-day risk of stroke was 3.8% while the composite outcome of death/stroke/MI was 8.2%. When stratified by age <70 and ≥ 70 years, the 30-day stroke rate was 0% versus 7.4% (p=0.03), and the composite outcome of death/stroke/MI was 2.6% versus 13.6% (p=0.02), respectively. CONCLUSIONS: Patients <70 years of age undergoing CAS have a low rate of major complications, comparing favourably with historical CEA adverse event rates, and supporting the recent carotid stenosis literature that in the younger population CAS has a similar complication rate compared to CEA.

Paranasal sinuses computed tomography in the initial evaluation of patients with suspected invasive fungal rhinosinusitis.

Invasive fungal rhinosinusitis (IFR) is a complication that presents mainly in immunocompromised patients. Paranasal sinuses computed tomography (PCT) is frequently obtained during initial evaluation of suspected cases. The objective of the study was to determine the imaging findings that suggest IFR in patients with hematological malignancies. In the retrospective case/control study, we included 14 patients with hematological malignancies that developed IFR in the Hospital Clínico de la Pontificia Universidad Católica de Chile between January 2005 and June 2009. Twenty patients with hematological malignancies, with suspected sinonasal infectious involvement requiring a PCT for initial evaluation, were chosen as the control group. Thirteen imaging parameters were compared between both groups. Osseous erosion and facial soft tissue thickening were statistically associated with the presence of IFR (p < 0.05). The presence of osseous erosion, facial soft tissue thickening, extrasinus extension or unilateral involvement had a positive predictive value of 100%, with an incidence among the total group of 12, 15, 9 and 9%, respectively. No patients with IFR had a normal PCT. Most PCTs in the initial evaluation of suspected IFR had nonspecific findings. The clinician must have a high index of suspicion and complement the workup with other diagnostic techniques to initiate appropriate treatment.