Low-dose radiotherapy to the lungs using an interventional radiology C-arm fluoroscope: Monte Carlo treatment planning and dose measurements in a postmortem subject.

Objective.The goal of this study was to use Monte Carlo (MC) simulations and measurements to investigate the dosimetric suitability of an interventional radiology (IR) c-arm fluoroscope to deliver low-dose radiotherapy to the lungs.Approach.A previously-validated MC model of an IR fluoroscope was used to calculate the dose distributions in a COVID-19-infected patient, 20 non-infected patients of varying sizes, and a postmortem subject. Dose distributions for PA, AP/PA, 3-field and 4-field treatments irradiating 95% of the lungs to a 0.5 Gy dose were calculated. An algorithm was created to calculate skin entrance dose as a function of patient thickness for treatment planning purposes. Treatments were experimentally validated in a postmortem subject by using implanted dosimeters to capture organ doses.Main results.Mean doses to the left/right lungs for the COVID-19 CT data were 1.2/1.3 Gy, 0.8/0.9 Gy, 0.8/0.8 Gy and 0.6/0.6 Gy for the PA, AP/PA, 3-field, and 4-field configurations, respectively. Skin dose toxicity was the highest probability for the PA and lowest for the 4-field configuration. Dose to the heart slightly exceeded the ICRP tolerance; all other organ doses were below published tolerances. The AP/PA configuration provided the best fit for entrance skin dose as a function of patient thickness (R2 = 0.8). The average dose difference between simulation and measurement in the postmortem subject was 5%.Significance.An IR fluoroscope should be capable of delivering low-dose radiotherapy to the lungs with tolerable collateral dose to nearby organs.

Guía de recomendación ACCHED-SCHGE para el funcionamiento de las unidades de endoscopia durante el brote de coronavirus (COVID-19) / Guideline recommendations ACHED-SCHGE for the endoscopy units during the Coronavirus outbreak (COVID-19)

The outbreak of COVID-19 disease has recently spread from its original place in Wuhan, Hubei province, China, to the entire world, and has been declared to be a pandemic by the World Health Organization in March 2020. All countries in America, in particular Chile, show an important increase in COVID-19 cases and deaths. The clinical manifestations of COVID-19 are a broad spectrum, from asymptomatic mild disease, to severe respiratory failure, shock, multiorgan dysfunction and death. Thus, high clinical suspicion and appropriate structure risk stratification are needed. Health care teams in endoscopy units, are at an increased risk of infection by COVID-19 from inhalation of droplets, mucosae contact, probably contamination due to contact with stools. Endoscopic aerosolized associated infections have also been reported. Different societies' recommendations, have recently placed digestive endoscopy (especially upper) among the high risk aerosol generating procedures (AGPs). In addition, live virus has been found in patient stools. On top of this, the infected health professionals may transmit the infection to their patients. Health care infection prevention and control (HCIPC), has been shown to be effective in assuring the safety of both health care personnel and patients. This is not limited to the correct use of personal protective equipment (PPE), but is based on a clear, detailed and well communicated HCIPC strategy, risk stratification, use of PPE, and careful interventions in patients with moderate and high risk of COVID-19. A conscientious approach regarding limited resources is important, as the simultaneous outbreak in all countries heavily affects the availability of health supplies. The Chilean Gastroenterology Society (SChGE) and Digestive Endoscopy Association of Chile (ACHED) are joining to provide continued updated guidance in order to assure the highest level of protection against COVID-19, for both patients and health care workers. This guideline will be updated online as needed.

El brote de la enfermedad denominada COVID-19, se ha extendido desde su origen en Wuhan, provincia de Hubei, China, a todo el mundo. La Organización Mundial de la Salud lo declaró pandemia en marzo de 2020. Todos los países de América, en especial Chile, presentan incremento de casos y fallecidos. Las manifestaciones clínicas de COVID-19 van desde una enfermedad leve, hasta insuficiencia respiratoria severa, shock, disfunción orgánica y muerte. Se necesita una alta sospecha clínica y una adecuada estratificación del riesgo. El equipo de salud en las unidades de endoscopia, tiene un mayor riesgo de COVID-19 que otras unidades clínicas y de apoyo diagnóstico, dada la mayor exposición a inhalación de gotas, contacto posible con mucosas y contaminación por contacto con deposiciones. Recomendaciones de diferentes sociedades colocan la endoscopia digestiva (especialmente la esofagogastroscopia o endoscopia digestiva alta, EDA) entre los procedimientos generadores de aerosoles (PGA) de alto riesgo. Además, se han encontrado virus viables en las deposiciones de los pacientes. Potencialmente, los profesionales de la salud infectados podrían contagiar a los pacientes. Se ha demostrado que la prevención y control de infecciones asociadas a la atención de salud (IAAS), son efectivos para garantizar la seguridad tanto del personal de salud, como de los pacientes. Esto no es solamente el correcto uso del equipo de protección personal (EPP), sino que se basa en una clara estrategia de IAAS, bien comunicada, con estratificación de riesgo, uso de EPP e intervenciones correctas en pacientes con riesgo moderado y alto. Es relevante un enfoque sobre los limitados recursos, dado la simultaneidad del brote en todos los países, que afecta la disponibilidad de insumos. La Sociedad Chilena de Gastroenterología (SChGE) y la Asociación Chilena de Endoscopia Digestiva (ACHED) publican esta guía actualizada para apoyar las buenas prácticas contra COVID-19, tanto para pacientes como para el equipo de salud. Esta guía podrá tener actualizaciones según avance la información disponible.

Hepatotoxicidad grave inducida por sertralina / Sertraline-induced severe hepatotoxicity

We report the case of a 19-year-old patient, with a history of traumatic liver damage, but with a normal liver profile at her first discharge; 1 month after the event, with post-traumatic stress disorder, treatment with 25 mg of sertraline was started every day; one month later, she develops severe hepatotoxicity without a specific etiology. According to the Naranjo algorithm, it is attributed as a probable case of sertraline hepatotoxicity. Management is carried out with support measures and suspension of the medication, and the patient recovers until she is asymptomatic, currently has normal liver tests

Reportamos el caso de una paciente de 19 años, con antecedentes de daño hepático traumático, pero con un perfil hepático normal en su primer alta; después de 1 mes del evento, con trastorno de estrés postraumático se inició tratamiento con 25 mg diarios de sertralina; un mes después, desarrolla una hepatotoxicidad severa sin etiología determinada. De acuerdo con el algoritmo de Naranjo, se atribuye como caso probable de hepatotoxicidad por sertralina. El manejo se realiza con medidas de apoyo y suspensión del medicamento, y la paciente se recupera hasta que se encuentra asintomática, actualmente tiene pruebas hepáticas normales

[Update on celiac disease]. / Enfermedad celíaca.Revisión.

The prevalence of Celiac disease in the general population is approximately 1% and remains undiagnosed in a significant proportion of individuals. Its clinical presentation includes the classical malabsorption syndrome, unspecific and extra-intestinal manifestations, and silent celiac disease. The serologic diagnosis has an elevated sensitivity and specificity and, at least in adult population, it must be confirmed by biopsy in every case. Diagnosis in subjects already on gluten free diet includes HLA typing and gluten challenge with posterior serologic and histologic evaluation. The core of the treatment is the gluten free diet, which must be supervised by an expert nutritionist. Monitoring must be performed with serology beginning at 3-6 months, and with histology two years after the diagnosis, unless the clinical response is poor. Poor disease control is associated with complications such as lymphoma and small bowel adenocarcinoma. In the future, it is likely that new pharmacologic therapies will be available for the management of celiac disease.

Enfermedad celíaca: revisión / Update on celiac disease

The prevalence of Celiac disease in the general population is approximately 1% and remains undiagnosed in a significant proportion of individuals. Its clinical presentation includes the classical malabsorption syndrome, unspecific and extra-intestinal manifestations, and silent celiac disease. The serologic diagnosis has an elevated sensitivity and specificity and, at least in adult population, it must be confirmed by biopsy in every case. Diagnosis in subjects already on gluten free diet includes HLA typing and gluten challenge with posterior serologic and histologic evaluation. The core of the treatment is the gluten free diet, which must be supervised by an expert nutritionist. Monitoring must be performed with serology beginning at 3-6 months, and with histology two years after the diagnosis, unless the clinical response is poor. Poor disease control is associated with complications such as lymphoma and small bowel adenocarcinoma. In the future, it is likely that new pharmacologic therapies will be available for the management of celiac disease.

Enfermedad celíaca: revisión / Celiac disease: a review

La Enfermedad Celiaca (EC) tiene una prevalencia cercana al 1% de la población general y se considera que hay un número importante de pacientes asintomáticos no diagnosticados. Su presentación clínica es variable comprendiendo el clásico síndrome de malabsorción, formas menores y la EC silente. El diagnóstico serológico tiene una elevada sensibilidad y especificidad y siempre debe confirmarse con biopsia. El diagnóstico en pacientes en dieta libre de gluten incluye test de tipificación de HLA y prueba de dieta con gluten con estudio serológico e histológico posterior. El pilar del tratamiento es la dieta libre de gluten, que debe ser supervisada por un nutriólogo con experiencia. La monitorización de la terapia debe realizarse con serología. La EC mal controlada puede determinar complicaciones como linfoma y adenocarcinoma de intestino delgado. En el futuro es probable que nuevas terapias farmacológicas sean de utilidad en el manejo de la EC.

Celiac disease has a prevalence near to 1% of general population and there is an important amount of asymptomatic people not yet diagnosed. Clinical presentation includes the classical malabsorption syndrome, minor and silent celiac disease. Serologic diagnosis has an elevated sensitivity and specificity, and must be confirmed by biopsy. Diagnosis in those on gluten free diet includes HLA type and gluten challenge with posterior serologic and histologic evaluation. The core of the treatment is the gluten free diet that must be supervised by an expert nutritionist. Monitoring is with serology. Poor disease control can determine complications such as lymphoma and small bowel adenocarcinoma. In the future, it is likely that new pharmacologic therapies will be available for the management of celiac disease.

Experiencia del uso de terapia biológica en pacientes con enfermedad inflamatoria intestinal en un hospital público / Experience in the use of biological therapy in IBD patients in a public hospital

Biological therapy plays an important role in the treatment of inflammatory bowel disease (IBD). However, the use of these drugs is limited due to fears about their side effects. Aim: To report the experience with the use of infliximab/adalimumab in IBD patients in a public hospital. Material and Methods: Descriptive study of a historical cohort of IBD patients treated with infliximab and adalimumab between April 2012 and July 2014. The clinical response was considered favourable when general, intestinal and extra intestinal symptoms subsided after the induction therapy. In addition, endoscopic and/or imaging response was evaluated at three and six months of treatment. Results: Fifteen out of 162 patients, aged 17 to 52 years (7 women) were included. Seven had Crohn´s Disease, 7 had ulcerative colitis and one had non-classifiable IBD. Biological therapy was indicated due to conventional refractory disease in all patients. All patients received combined treatment with immunosuppressive medications. A favorable clinical response was observed in 93 percent after induction therapy and 73 percent showed endoscopic/imagining remission after 3-6 months. Only one patient experienced side effects associated to the biological therapy, which did not result in discontinuation or treatment interruption. Conclusions: In this cohort of IBD patients treated in a public hospital, the use of infliximab/adalimumab was associated with favorable clinical and endoscopic evolution, post induction therapy with no major side effects.

La terapia biológica tiene un papel fundamental en el tratamiento de la enfermedad inflamatoria intestinal (EII). Sin embargo, el uso de estos fármacos es escaso debido a los costos y los temores sobre los efectos secundarios. Objetivo: Dar a conocer la experiencia en el uso de infliximab/adalimumab en pacientes con EII atendidos en un hospital público de nuestro país. Material y Métodos: Estudio descriptivo de una cohorte histórica de pacientes con EII tratados con infliximab y adalimumab entre abril de 2012 y julio de 2014. La respuesta clínica fue considerada favorable cuando los síntomas generales, intestinales y extra-intestinales desaparecieron después de la terapia de inducción. Además se evaluó la respuesta endoscópica/radiológica a los 3 y 6 meses de tratamiento. Resultados: De un total de 162 pacientes con EII, 15 fueron tratados con terapia biológica, con edad entre 17-52 años (7 mujeres). Siete presentaban el diagnóstico de enfermedad de Crohn, siete colitis ulcerosa y uno EII no clasificable. En todos se inició terapia biológica debido a la presencia de refractariedad a la terapia convencional. Todos recibieron terapia combinada con inmunosupresores. Se observó una respuesta clínica favorable en 93 por ciento después de la terapia de inducción y 73 por ciento tuvo una mejoría endoscópica después de 3-6 meses. Sólo un paciente presentó un evento adverso a terapia biológica, el cual no motivó la interrupción del tratamiento. Conclusiones: En esta cohorte de pacientes con EII tratados en un hospital público, el uso de infliximab/adalimumab se asoció con mejoría clínica y endoscópica post terapia de inducción, sin mayores efectos secundarios.

Trasplante de microbiota fecal en paciente con colitis ulcerosa e infección refractaria por: revisión de la literatura a partir de un caso clínico / Fecal microbiota transplantation in patient with ulcerative colitis and refractory infection due to: review of the literature based on a clinical case

Infection (CDI) is increasing both in the hospital environment as in the outpatient setting, and is associated with prior use of antibiotics, hospitalizations and inflammatory bowel disease (IBD), among others. It is also characterized by a high rate of recurrence with the usual antibiotic treatment, which increases with greater number of episodes, reaching up to 65 percent. In this context, the transplantation of fecal microbiota (FMT) emerges as recurrent CDI therapy, achieving success rates exceeding 90 percent, including in IBD patients, with minimum rates of recurrence. To achieve such efficiency, the colonization by the donated microbiota in the recipient is critical. The role of FMT is still unclear in IBD therapy not associated with CDI. Although there are great differences in the methodology of FMT, the process has been standardized even creating banks of frozen fecal samples, without reducing its effectiveness. FMT is a safe procedure, without serious adverse events, and accepted by the potential beneficiary population. There are few reported cases of refractory CDI management with FMT. Since 2012, the FMT in CDI and IBD publications have increased significantly, but in our country there are only few reports of this therapeutic strategy. We present a patient with ulcerative colitis and conventional antimicrobial management resistant CDI, which was successfully treated with FMT in a public hospital in Chile.

La infección por Clostridium difficile (ICD) está en aumento tanto en el ambiente hospitalario como ambulatorio, y se asocia a uso previo de antibióticos, hospitalización y enfermedades inflamatorias intestinales (EII), entre otros. Se caracteriza además por su alta tasa de recurrencia con el tratamiento antimicrobiano habitual, que aumenta con el mayor número de episodios alcanzando hasta 65 por ciento. En este contexto, el trasplante de microbiota fecal (TMF) surge como terapia para la ICD recurrente, logrando tasas de éxito superiores a 90 por ciento, incluyendo pacientes con EII, con mínimas tasas de recurrencia. Para lograr esa eficacia, la colonización por la microbiota donada en el receptor es fundamental. Aún no está claro el rol del TMF en la terapia de EII no asociada a ICD. Aunque existe gran heterogeneidad en la metodología del TMF, el proceso se ha ido estandarizando incluso hasta llegar a la creación de bancos de muestra fecal congelada, sin disminuir su efectividad. El TMF es un procedimiento seguro, sin eventos adversos graves y aceptado por la población potencialmente beneficiaria de él. Existen pocos casos publicados de manejo de ICD refractaria con TMF. Desde el 2012 el número de publicaciones sobre TMF en ICD y en EII ha aumentado considerablemente, sin embargo, en nuestro país los reportes sobre esta estrategia terapéutica son escasos. Presentamos el caso de un paciente con colitis ulcerosa e ICD refractaria al manejo antimicrobiano habitual, que se trató exitosamente con TMF en un hospital público de Chile.

Sensibilidad a citostáticos de células de tumores cerebrales humanos en cultivo / Sensitivity to cytostatics of cells of human brain neoplasm in culture

Los cultivos de gliomas malignos se han realizado con el objeto de conocer su biología, estudiar nuevas drogas antineoplásicas y determinar la sensibilidad diferencial a citostáticos. Catorce pacientes con diagnósticos clínico y radiológico sugestivos de tumor cerebral maligno fueron seleccionados de acuerdo a criterios específicos, lo que incluyó la evaluación según el esquema de Karnofsky, el cual determina el estado funcional independiente del paciente. Se realizó la resección quirúrgica, se efectuó el estudio histopatológico y se tomó una muestra del tumor para cultivo en monocapas. La confluencia celular se alcanzó entre 15 y 45 días y los cultivos fueron expuestos a los citostáticos (1,3-bis(2-cloroetil)-1- nitrosouréa, cisplatino o vincristina por una hora. Se determinó la integridad de la membrana mediante la exclusión del colorante azúl de Tripán. Se encontraron diferencias estadísticamente significativas entre las drogas utilizadas y entre los tumores, incluso con el mismo diagnóstico histopatológico, lo cual indica la existencia de resistencia diferencial de las células tumorales a los citostáticos utilizados. Este estudio constituye un ensayo que sustenta la realización de evaluaciones a largo plazo con el fin de emplear una quimioterapia específica en pacientes en los que probablemente se combine ésta con la radioterapia

Perinatal management of unanticipated congenital laryngeal atresia.

Unless ventilation is achieved within minutes of delivery, patients with congenital laryngeal atresia will not survive. There are 2 settings in which survival is more likely: a tracheotomy may be immediately performed in the delivery room, or a communication may exist between the airway and the pharynx, allowing for air exchange. In the latter case, there are no characteristic findings on prenatal sonography to suggest the diagnosis and to ensure that preparations for immediate tracheotomy are made. We describe a neonate with unanticipated laryngeal atresia and a high tracheoesophageal fistula. Ventilation was maintained first by face mask and then by esophageal intubation until a tracheotomy could be performed. This report provides detailed photodocumentation of the anomaly, discusses the mechanism of air exchange, reviews the relevant embryological development, and outlines a protocol for perinatal management of unanticipated laryngeal atresia.

Rigid fixation of vascularized bone grafts in mandibular reconstruction.

OBJECTIVE: To evaluate the nature of complications and complication rates with the use of three different reconstruction plates for the rigid fixation of vascularized bone grafts in oromandibular reconstruction. DESIGN: We conducted a case series of 95 patients over a 6-year period, with a minimum follow-up of 6 months and a maximum follow-up of 66 months. SETTING: Academic tertiary referral medical center. PATIENTS: Forty-eight patients had vascularized bone grafts fixated to native mandible with AO stainless steel reconstruction plates; 25 patients, with AO titanium plates; and 22 patients, with titanium hollow screw reconstruction plates (THORPs). Types of vascularized flaps, mandibular defects to be reconstructed, and use of radiation therapy were similar among the three groups. INTERVENTION: The surgical approach involved oromandibular reconstruction with a vascularized bone graft rigidly fixated with a reconstruction plate. OUTCOME MEASURES: Clinically and radiographically noted complications and resultant treatment. RESULTS: In the grafts fixated with AO stainless steel reconstruction plates, three plate fractures, seven instances of loose screws, eight plate exposures, and two cases of nonunion occurred. No cases of plate fracture or nonunion occurred in the titanium or THORP groups. One titanium plate and two THORPs were exposed during the study period. One instance of loose screws occurred in the titanium group; none in the THORP group. Seventy-four percent of those complications occurred within 12.4 months (the mean follow-up time of the THORP group). The incidence of complications in the stainless steel group was significantly greater than that in the titanium or THORP groups. No statistically significant increase in the rate of complications was noted when radiation therapy was used as a component of treatment. CONCLUSIONS: To our knowledge, this is the first study to compare three different reconstruction plates for fixation in vascularized bone reconstruction of the mandible. AO THORPs are now used almost exclusively to rigidly fixate vascularized bone grafts because of their advanced design and their potential for osseointegration and because fewer screws are necessary to attain adequate fixation than with conventional AO reconstruction plates.

Radial forearm flaps.

Restoration of oral cavity and pharyngeal function following ablative surgery remains an elusive goal. Conventional reconstructive methods often achieve satisfactory wound healing, but the introduction of a dynamic anesthetic and bulky flaps into the oral cavity can interfere with the function of the residual soft tissues. This article examines the anatomy, harvest technique, and applicability of neurosensory radial forearm flaps to head and neck reconstruction with special attention to the attributes of this donor site which, at present, make the radial forearm flap the flap of choice for the reconstruction of a variety of oral cavity and pharyngeal defects.

The iliac crest composite flap for oromandibular reconstruction.

Reconstruction of oromandibular defects following tumor ablation remains a complex endeavor. Its outcome greatly influences a cancer patient's quality of life and ability to become re-integrated into society. The number and variety of reconstructive options attest to the complexity of the problem and to the failure of any one method to demonstrate its superiority. We have favored the iliac crest-internal oblique free flap because of the quality of the bone and flexibility of the soft tissues. These qualities make this flap the ideal option for reconstruction of through-and-through defects of the oral cavity. Our experience reveals that this flap is highly successful in restoring functional mastication in most patients and is associated with minimal donor site morbidity. It is important to recognize, however, that it represents one of many available techniques for the reconstruction of composite oral mandibular defects.

A modified design of the buried radial forearm free flap for use in oral cavity and pharyngeal reconstruction.

OBJECTIVE: We present a new design for the radial forearm flap that includes a small monitor segment that is connected to the primary skin paddle by a fascial subcutaneous segment of tissue. This design modification permits buried flaps to be easily monitored and provides vascularized tissue coverage of the flap vessels as well as the great vessels in the neck. Immediate augmentation of the radical neck deformity can be achieved. SETTING: This study was conducted at a referral center. PATIENTS: Fifteen patients with squamous cell cancer of the pharynx and tongue base were included in this study. The defects in these patients were judged to be best reconstructed with a radial forearm free flap. RESULTS: All free flaps in this series survived. There was one case, described in detail, in which the fascial subcutaneous portion of the flap was exposed to salivary contamination. The flap vessels remained well protected and flap viability was unimpaired.

Simultaneous interstitial radiotherapy with regional or free-flap reconstruction, following salvage surgery of recurrent head and neck carcinoma. Analysis of complications.

OBJECTIVE: Reports on complications following brachytherapy offer conflicting views on the benefit of locoregional flap coverage of the implanted tumor bed. This study reviews complications following pedicled and free-flap coverage of brachytherapy sources after salvage surgery for recurrent head and neck carcinoma. DESIGN: Retrospective chart review. SETTING: Academic tertiary referral center. PARTICIPANTS: Fifteen patients with advanced, radiorecurrent carcinomas of the head and neck, treated between 1988 and 1992. INTERVENTION: All patients underwent surgical resection and implantation of the tumor bed with iridium 192 after-loading catheters (13 patients) or iodine 125 seeds (two patients). The average dose of interstitial radiotherapy supplied was 50.24 +/- 45.19 Gy (mean +/- SD). Coverage of the implanted tumor bed was achieved with regional myocutaneous flaps in 10 patients and microvascular free flaps in five patients. OUTCOME MEASURE: All wound and healing complications were identified. Patients were followed up for a minimum of 3 months. RESULTS: No significant complications were encountered. No flap, pedicled or free, demonstrated any degree of necrosis. Four minor complications developed in the group of patients who underwent reconstruction with pedicled myocutaneous flaps. One orocutaneous fistula developed in a patient in whom a radial forearm was used to reconstruct a posterior pharyngeal wall defect. CONCLUSIONS: An expectation of increased postoperative morbidity should not interfere with the decision to proceed with multimodality salvage therapy of patients with advanced, recurrent head and neck tumors. The advantages of free tissue transfer in the reconstruction of head and neck defects are not compromised when the flaps are simultaneously utilized to provide coverage for brachytherapy sites.