Abstract In Mexico, citrus farming represents one of the most important economic activities for national fruit growing, with a production of 8.8 million tonnes and an economic spillover of more than 47 billion pesos per year. Nonetheless, production is affected by pests and diseases, with Huanglongbing (HLB), ‘yellow dragon’ or citrus greening, standing out as the most devastating disease worldwide, caused by a proteobacterium of the genus Candidatus Liberibacter (Ca. L.). Because there is no effective method to control this disease, correct and timely detection can significantly reduce its spread. The purpose of this review is to compile methods used for detecting the presence of Ca. L. in citrus plants, covering general aspects of the symptomatology of the disease, molecular methods for accurate and rapid detection when sampling both in plants and in the vector. In addition, different protocols are mentioned that analyze some compounds produced during infection with Ca. L. and images in citrus with HLB.

Resumen En México, la citricultura representa una de las actividades económicas más importantes para la fruticultura nacional, con una producción de 8.8 millones de toneladas y una derrama económica de más de 47 mil millones de pesos al año. Sin embargo, la producción se ve afectada por plagas y enfermedades, destacando el Huanglongbing (HLB), ‘dragón amarillo’ o enverdecimiento de los cítricos, como la enfermedad más devastadora a nivel mundial, ocasionada por una proteobacteria del género Candidatus Liberibacter (Ca. L.). Debido a que no existe un método efectivo para controlar esta enfermedad la correcta y oportuna detección puede reducir significativamente su diseminación. El propósito de la presente revisión es recopilar métodos que se emplean para la detección de la presencia de Ca. L. en plantas de cítricos, cubriendo aspectos generales sobre la sintomatología de la enfermedad, métodos moleculares para una precisa y rápida detección al realizar el muestreo tanto en plantas como en el vector. Asimismo, se mencionan diferentes protocolos que analizan algunos compuestos producidos durante la infección con Ca. L. e imágenes en cítricos con HLB.

Abstract Introduction: Immunosuppressive treatments have improved graft and patient survival rates, but can increase the incidence of post-transplant infections. Objectives: To analyze data from kidney transplant patients and describe the pathogens responsible for the infections they experience. Methods: Longitudinal, analytical, observational study of 103 patients who underwent kidney transplantation. The follow-up period was 5.07 ± 1.28 years. Results: Overall mortality rate was 10.68% and graft loss rate was 14.56%. Regarding recipient risk of death, the Cox regression model showed a hazard ratio (HR) of 5.66 for positive bacterial cultures and 2.22 for positive extended-spectrum beta-lactamase (ESBL)-producing strains; as for graft loss, HR was 4.59 in those with positive bacterial cultures and 4.25 in those who were positive for ESBL-producing strains Conclusions: Significant death risk was found in kidney transplant recipients with positive bacterial cultures and an increased risk of graft loss in those with positive bacterial cultures and in those who were positive for ESBL-producing Enterobacteriaceae isolates. The rate of ESBL-producing Enterobacteriaceae is high, and stricter strategies are therefore necessary to control the use of antibiotics.

Resumen Introducción: Los tratamientos inmunosupresores han mejorado las tasas de supervivencia del injerto y del paciente, pero pueden incrementar las infecciones postrasplante. Objetivos: Analizar los datos de pacientes con trasplante renal y describir las bacterias responsables de las infecciones que presentan. Métodos: Estudio observacional, longitudinal y analítico de 103 pacientes sometidos a trasplante renal. El periodo de seguimiento fue de 5.07 ± 1.28 años. Resultados: La tasa de mortalidad fue de 10.68 % y la de pérdida del injerto de 14.56 %. Respecto al riesgo de muerte del receptor, el modelo de regresión de Cox mostró un cociente de riesgo (HR, hazard ratio) de 5.66 en los pacientes con cultivo bacteriano positivo y de 2.22 en aquellos con cepas productoras de betalactamasas de espectro extendido (BLEE); en cuanto a la pérdida del injerto, el HR fue de 4.59 en quienes tuvieron cultivo bacteriano positivo y de 4.25 en aquellos con cepas productoras de BLEE. Conclusiones: Se encontró riesgo significativo de muerte en receptores de trasplante renal con cultivo bacteriano positivo y mayor riesgo de pérdida del injerto en aquellos con cultivo bacteriano positivo y aislamiento de cepas productoras de BLEE. La tasa de enterobacterias productoras de BLEE es alta, por ello son necesarias estrategias más estrictas para controlar del uso de antibióticos.

Abstract Influenza is a costly disease for the population. It is a cause of seasonal morbidity and mortality, epidemics and pandemics or syndemics. Given the variability of the virus, surveillance systems are implemented in order to update the strains and include them in the annual influenza vaccine. This vaccine is currently recommended in some high-risk groups. However, universal vaccination remains controversial. Objective: To evaluate the evidence and describe the position of a panel of experts on the relevance of universal vaccination against influenza virus. Material and methods: Five clinical questions were asked, whereby a systematic search of the literature in electronic sources and a Delphi panel was carried out. The evidence was analyzed and recommendations were issued by the experts. Results: The group of experts recommends vaccinating the population starting at six months of age include people who live with egg protein allergy; with comorbidities (diabetes, obesity, cancer) health workers and pregnant women. Conclusions: Vaccination, starting with vulnerable groups, is a necessary, ethical and cost-effective strategy. However, extending coverage to achieve universal vaccination could reduce the transmission of the disease and its consequences in the population.

Resumen La influenza es una enfermedad costosa para la población. Es causa de morbimortalidad estacional, epidemias y pandemias o sindemias. Debido a la variabilidad del virus, se implementan sistemas de vigilancia para actualizar las cepas e incluirlas en la vacuna antiinfluenza anual. Actualmente se recomienda esta vacuna en algunos grupos de alto riesgo. Sin embargo, la vacunación universal es aún controvertida. Objetivo: Evaluar la evidencia y describir la posición de un panel de expertos sobre la pertinencia de la vacunación universal contra el virus de influenza. Material y métodos: Se realizaron cinco preguntas clínicas, con las que se realizó una búsqueda sistemática de la literatura en fuentes electrónicas y un panel Delphi. Se analizó la evidencia y se emitieron recomendaciones por los expertos. Resultados: El grupo de expertos recomienda vacunar a la población desde los seis meses de edad e incluir a personas que viven con alergia a la proteína del huevo, con comorbilidades (diabetes, obesidad, cáncer), trabajadores de la salud y embarazadas. Conclusiones: La vacunación, iniciando con los grupos vulnerables, es una estrategia necesaria, ética y costo-efectiva. Sin embargo, extender la cobertura para lograr la vacunación universal podría disminuir la transmisión de la enfermedad y sus consecuencias en la población.

Abstract The authors of the image chapters of the National Association of Cardiologists of Mexico (ANCAM) and the Mexican Society of Cardiology (SMC), as well as personnel from the Department of Medicine and Nutrition of the University of Guanajuato, together with prominent experts in cardiovascular imaging from Mexico, have collaborated in the review, analysis and expansion of the various health strategies published in the first year of the coronavirus disease 2019 (COVID-19) pandemic, to safely perform cardiac imaging studies. This update aims to reduce the risk of COVID-19 transmission among patients and health-care personnel in the CT, MRI, and nuclear cardiology services. This work was expanded with supplementary information available free of charge on the website www.ancam-imagen.com.

Resumen Los capítulos de imagen de la Asociación Nacional de Cardiólogos de México (ANCAM) y de la Sociedad Mexicana de Cardiología (SMC), así como personal del Departamento de Medicina y Nutrición de la Universidad de Guanajuato, en conjunto con destacados expertos de la imagen cardiovascular en México, han colaborado en la revisión, análisis y ampliación de las diversas estrategias sanitarias publicadas en los primeros 15 meses de la pandemia de enfermedad por coronavirus 2019 (COVID-19) para realizar con seguridad los estudios de imagen cardiaca; esta actualización tiene como objetivo principal disminuir el riesgo de transmisión de la COVID-19 entre los pacientes y el personal de salud en los servicios de tomografía, resonancia y cardiología nuclear. Este trabajo se amplió con información suplementaria disponible sin costo en el sitio www.ancam-imagen.com.

Abstract Introduction: Clostridioides difficile causes diarrhea and pseudomembranous colitis. Its diagnosis is made with glutamate dehydrogenase (GDH) or toxins A and B detection and is confirmed with nucleic acid amplification tests. Objective: To define if GDH determination is redundant to that of toxins. Methods: Retrospective, observational study in diarrheal stools of patients with suspected Clostridioides difficile infection. Toxins and GDH were determined by immunochromatography. Bayesian simulation was performed with likelihood ratios; a p-value < 0.05 was regarded as significant. Results: 329 GDH and toxin A and B results were analyzed. Clostridioides difficile infection prevalence was 18.2 %. Sensitivity and specificity of the GDH test were 0.90 and 0.89, respectively. Positive likelihood ratio was 8.9, and negative was 0.11. Conclusions: A negative GDH result considerably reduces the probability of infection but does not rule it out. Clostridioides difficile toxins detection may be necessary in institutions where nucleic acid amplification is not affordable or accessible.

Resumen Introducción: Clostridioides difficile causa diarrea y colitis pseudomembranosa. Su diagnóstico se realiza con la detección de glutamato-deshidrogenasa (GDH) o las toxinas A y B y se confirma con pruebas de amplificación de ácidos nucleicos. Objetivo: Definir si la determinación de GDH es redundante a la de las toxinas. Métodos: Estudio observacional retrospectivo de muestras fecales de pacientes con sospecha de infección por Clostridioides difficile. Las toxinas y GDH se determinaron mediante inmunocromatografía. Se realizó una simulación bayesiana con los cocientes de probabilidad; se consideró significativo un valor de p < 0.05. Resultados: Se analizaron 329 resultados de GDH y toxinas A y B. Se encontró una prevalencia de infección de Clostridioides difficile de 18.2 %. La sensibilidad y especificidad de la prueba de GDH fue de 0.90 y 0.89, respectivamente. El cociente de probabilidad positivo fue de 8.9 y el negativo, de 0.11. Conclusiones: Un resultado negativo de GDH disminuye considerablemente la probabilidad de infección, pero no la descarta. La detección de toxinas de Clostridioides difficile puede ser necesaria en instituciones donde la amplificación de ácidos nucleicos no es económica o accesible.

RESUMO: Uma série de casos foi estudada para determinar a frequência de causas do aborto em bovinos leiteiros no Uruguai. A amostra, de 102 casos, foi composta por 53 fetos, 35 fetos com placentas e 14 placentas sem feto associado. Todos os casos foram submetidos a exames patológicos macroscópicos e microscópicos, além de testes microbiológicos e sorológicos. A etiologia foi determinada em 54 (53%) dos casos, 51 dos quais foram causados por agentes infecciosos. Nos 102 casos observados, 30 (29%) foram causados por Neospora caninum, seis (6%) por Coxiella burnetii e dois (2%) por Campylobacter fetus subsp. venerealis. O vírus da Parainfluenza-3 e Salmonella enterica serovar Newport causaram um aborto cada. Bactérias oportunistas (Escherichia coli, Streptococcus sp., Staphylococcus sp., Mannheimia sp., Trueperella pyogenes e Providencia stuartii) foram associadas a 11 abortos. Em dois casos, a morte fetal foi atribuída a distocia e, em um caso, o feto apresentava mesotelioma congênito. A infecção pelo vírus da diarreia viral bovina (BVDV) foi identificada em três fetos; dois dos quais foram co-infectados e apresentavam lesões típicas de N. caninum. Não foram observadas lesões no outro feto infectado pelo BVDV. Leptospira interrogans foi identificada em um feto sem lesões. Apesar da relativamente baixa taxa de sucesso no diagnóstico etiológico nos casos de aborto em bovinos, é necessário o diagnóstico sistemático dos abortos para estabelecer estratégias de prevenção e controle. Isso também facilita o monitoramento e a vigilância de doenças reprodutivas em bovinos leiteiros, algumas das quais representam um risco para a saúde pública.

ABSTRACT: A case series study was conducted to determine the frequency of causes of abortion in dairy cattle in Uruguay. The sample size of 102 cases was composed of 53 fetuses, 35 fetuses with placentas, and 14 placentas without an associated fetus. All cases underwent gross and microscopic pathologic examinations as well as microbiological and serological testing. The etiology was determined in 54 (53%) of cases, 51 of which were caused by infectious agents. Within the observed 102 cases, 30 (29%) were caused by Neospora caninum, six (6%) by Coxiella burnetii and two (2%) by Campylobacter fetus subsp. venerealis. Bovine Parainfluenza-3 virus and Salmonella enterica serovar Newport caused one abortion each. Opportunistic bacteria (Escherichia coli, Streptococcus sp., Staphylococcus sp., Mannheimia sp., Trueperella pyogenes, and Providencia stuartii) were associated with 11 abortions. In two cases the fetal death was attributed to dystocia, and in one case the fetus had a congenital mesothelioma. Bovine viral diarrhea virus (BVDV) infection was identified in three fetuses; two of which were co-infected with and had typical lesions of N. caninum. No lesions were observed in the other fetus infected by BVDV. Leptospira interrogans was identified in one fetus without lesions. Despite the relatively low overall success rate in establishing an etiological diagnosis in cases of abortion in cattle, a systemic workup of bovine abortion is necessary to establish prevention and control strategies. This also facilitates monitoring and surveillance of reproductive diseases in dairy cattle, some of which represent a risk to public health.

ABSTRACT Objective: To analyze the accuracy of endoscopic ultrasound (EUS) in the evaluation of ampullary tumors compared to histopathology (HP) staging. Methods: A retrospective diagnostic test study. Patients with ampullary tumors staged by EUS and postpancreatoduodenectomy HP attended during 2012-2018 at tertiary level hospital. Results: 14 patients with adenocarcinoma where included. Tumor size measured by EUS showed an adequate correlation (R = 0.65; p= 0.01) with HP. The accuracy in the evaluation of duodenal wall, pancreatic, and biliary duct invasion was 78.5, 78.5 and 57.1%, respectively. By HP, there were three T1 (21.4%), two T2 (14.2%) and nine T3 (64.2%). The accuracy of T and N staging by EUS was 71.4% (kappa = 0.50) and 50% (kappa = −0.04) respectively. There were more staging errors in patients with biliary stent. Conclusion: EUS was useful in estimating tumor size, duodenal wall and pancreatic invasion. Limitation was found in the evaluation of biliary duct invasion, as well as overestimation of T stage and underestimation of N stage. It is necessary an increased effort in ultrasonography training. We suggest EUS testing before biliary stenting.

Resumen Objetivo: Comparar el ultrasonido endoscópico (USE) en la valoración de los tumores ampulares primarios (TAp) con referencia al estudio histopatológico (HP). Método: Estudio retrospectivo prolectivo de pruebas diagnósticas en pacientes con TAp estadificados por USE y pancreatoduodenectomía con estudio HP, atendidos de 2012 a 2018 en un hospital de tercer nivel de atención. Resultados: Fueron incluidos14 pacientes con adenocarcinoma. El tamaño del tumor medido por USE mostró una adecuada correlación (R = 0.65; p = 0.01) con el HP. La exactitud en la determinación de la invasión a la pared duodenal, el páncreas y el conducto biliar fue del 78.5, el 78.5 y el 57.1%, respectivamente. Por HP hubo tres T1 (21.4%), dos T2 (14.2%) y nueve T3 (64.2%). La exactitud del estadiaje T y N por USE fue del 71.4% (kappa = 0.50) y del 50% (kappa = −0.04), respectivamente. Los errores en la estadificación fueron más frecuentes en los pacientes con prótesis biliar. Conclusión: El USE mostró utilidad en la determinación del tamaño tumoral y de la invasión al duodeno y al páncreas, y más limitada en la determinación de la invasión al conducto biliar por presencia de prótesis. Se observa una sobreestimación del estadiaje T y una subestimación del N. Es necesario mayor capacitación y sugerimos realizarse antes de colocar una prótesis biliar.

Abstract Background The incidence of dengue in Mexico has increased in recent decades. It has been suggested that dengue outbreaks may compromise treatment quality in hospitals. Objective The objective of the study was to quantify the burden imposed by dengue on hospital services in Mexico. Methods We analyzed 19.2 million records contained in the database of hospital services of the Mexican Ministry of Health between 2008 and 2014. The number of admissions due to dengue was compared to other potentially preventable hospitalizations. Hospital departments were categorized to reflect dengue-related activity as high dengue activity (HDA), low dengue activity (LDA), or zero dengue activity departments, and the impact of dengue activity on general in-hospital mortality in HDA departments was assessed. Results Dengue was the cause of more hospital admissions than most of the potentially preventable prevalent acute and chronic conditions and other infectious diseases. In HDA departments, dengue patient load was found to be a significant risk factor for overall in-hospital mortality. There was an approximately two-fold higher dengue case-fatality rate in LDA versus HDA departments, irrespective of dengue severity. Conclusions This study confirms that dengue is an important cause of hospitalization in Mexico and highlights the impact of dengue activity not only on dengue case-fatality rate but also on the overall in-hospital mortality.

Since the advent of bare metal and drug-eluting stents, the surgical revascularization have declined considerably, however the thrombosis and in-stent restenosis are important complications of these devices. There are several factors that predispose to thrombosis and in-stent restenosis. Conventional angiography has serious limitations to determine the causes of stent failure. Optical coherence tomography is a very sensitive technique to determine the cause of thrombosis and in-stent restenosis.

Desde la llegada de los stents convencionales y farmacoactivos han disminuido considerablemente los eventos de revascularización quirúrgica, sin embargo la trombosis y reestenosis son 2 factores que, aunque han disminuido, permanecen como complicaciones importantes. Existen varios factores que predisponen a la trombosis y a la reestenosis intrastent. La angiografía convencional tiene serias limitaciones para determinar las causas de la falla del stent. La tomografía de coherencia óptica es una técnica sumamente sensible para determinar las causas de trombosis y reestenosis del stent.

Objective. To know the quality of the water from hospitals and the risks that poor chlorination implies. Methods. We analyzed 90 water specimens from 15 hospitals (9 from the private and 6 from the public sector). Specimens were obtained from three areas (hospitalization ward, operating room, and kitchen) in two visits. Results. By microbiologic analysis, we found 30 (33.3 %) contaminated specimens. By chemical analysis, we found only 49 (54.5 %) specimens with adequate chlorination (> 1 mg/L). Of the 30 contaminated specimens, only 7 (23.3%) had adequate chlorination. On the other hand, of the 60 specimens without contamination, 42 (79%) had adequate chlorination (<img border=0 id="_x0000_i1025" src="../../../../../img/revistas/ric/v58n5/a8s1.jpg"> - 17.561, p < 0.001). The significant difference was sustained when the criterion for appropriate chlorination was established at > 0.5 mg/L. Conclusions. Hospitals require guidelines for water chlorination and testing to maintain it at > 0.5 mg/L in every point of use.

Objetivo. Conocer la calidad del agua en hospitales y los riesgos de contaminación bacteriana por cloración insuficiente. Material y métodos. Analizamos 90 especímenes de agua de 15 hospitales (nueve del sector privado y seis del público). Los especímenes se obtuvieron de tres áreas (hospitalización, quirófano y cocina) en dos visitas diferentes. Resultados. Por análisis microbiológico, encontramos 30 de los 90 especímenes contaminados (33.3%). Por análisis químico, encontramos que sólo 49 (54.4%) especímenes tuvieron cloración suficiente (> 1 mg/L). De los 30 especímenes contaminados sólo siete (23.3%) tenían cloración suficiente. Por otro lado, de los 60 especímenes sin contaminación, 42 (79%) tenían cloración suficiente (<img border=0 id="_x0000_i1026" src="../../../../../img/revistas/ric/v58n5/a8s1.jpg"> = 17.561, p < 0.001). La significancia se sostuvo al considerar como criterio de cloración suficiente un nivel > 0.5 mg/L. Conclusiones. Todo hospital requiere un manual de cloración del agua y verificar que mantenga niveles mínimos de 0.5 mg/L en todas las áreas.

OBJECTIVES. As Klebsiella, Enterobacter and Serratia are capable of growth in IV fluids and these bacteria are commonly implicated in nosocomial bacteremia, a control strategy through microbiological surveilance of in-use parenteral solutions is proposed. MATERIAL AND METHODS. A second level general teaching hospital, serving low-income patients. Through four consecutive strategies, a continous surveillance program of IV fluids sterility in pediatric wards was stablished in 1992. During the first stage all of the in -use solutions were cultured. During the second stage randomly selected samples were studied. Third stage was designed as a case-control study. The last stage included samples drawn in convenience. Positive cultures point out eventual infusion mishandling, as well as high-risk areas and patients. RESULTS. After culturing 1940 parenteral solutions, infusion contamination rates decreased from 29.6% in 1992 to 12.9% in 1997 (p< 0.001). The proportion of Gram-negative rods isolated from blood cultures went from 72.7% to 40.85% (p< 0.0001), and the nosocomial bacteremia rate dropped from 3.12 to 1.54 per 100 discharges. CONCLUSIONS. The program has enabled us to: 1) Detect and control eventual bacteremia outbreaks; 2) Assess the endemic infusion contamination rate; 3) Arouse healthcare workers awareness about infusion line precautions; 4) Have a suitable surveillance strategy according to our laboratory's workload.

OBJETIVO. Dado que Klebsiella, Enterobacter y Serratia se multiplican en soluciones parenterales y son responsables de una elevada proporción de bacteriemias en los hospitales de México, se propone una estrategia de control mediante la vigilancia microbiológica de las soluciones en uso. MATERIAL Y MÉTODOS. Hospital de enseñanza de segundo nivel con 193 camas. Atiende principalmente pacientes de escasos recursos. En 1992 se inició la vigilancia de la esterilidad de las soluciones parenterales en los servicios pediátricos mediante cuatro estrategias: durante la primera etapa se cultivó el total de soluciones en uso. Durante la segunda se cultivaron muestras aleatoriamente elegidas. Tercera y cuarta etapas con muestreo controlado y dirigido, respectivamente. RESULTADOS. Se han cultivado 1940 infusiones. Se ha observado una reducción de la tasa de contaminación (de 29.6% en 1992 a 12.9% en 1997, p< 0.001). Asimismo se redujo la proporción de bacilos gramnegativos aislados en sangre (72.7% vs 40.85%, p< 0.001) y las bacteriemias nosocomiales primarias (BNP) (3.12 vs 1.54 por 100 egresos, p< 0.0001). CONCLUSIONES. La detección de contaminantes señala posibles fallas en el manejo parenteral, áreas de riesgo y pacientes potencialmente afectados. El programa permite estudiar el nivel endémico de contaminación de infusiones y limitar los brotes de bacteriemias nosocomiales primarias a un costo bajo.