Tattoos: risks and complications, clinical and histopathological approach.

BACKGROUND: Skin modification through tattoos is as old as humanity itself. However, this trend is on the rise, and with the use of different types of pigments and application practices, both cutaneous and systemic complications can arise. Adverse reactions can be grouped into five classes: inflammatory, infectious, neoplastic, aesthetic, and miscellaneous. On histopathology, inflammatory reactions can exhibit a lichenoid pattern or present as spongiotic dermatitis, granulomatous reactions, pseudolymphoma, pseudoepitheliomatous hyperplasia, or scleroderma/morphea-like changes. This article reviews tattoo complications, including their clinical and histopathological characteristics. METHODS: An open search was conducted on PubMed using the terms "tattoo", "complications", and "skin". No limits were set for period, language, or publication type of the articles. RESULTS: Reactions to tattoos are reported in up to 67% of people who get tattooed, with papulonodular and granulomatous reactions being the most common. Some neoplastic complications have been described, but their causality is still debated. Any pigment can cause adverse reactions, although red ink is more frequently associated with them. Patients with pre-existing dermatoses may experience exacerbation or complications of their diseases when getting tattoos; therefore, this procedure is not recommended for this patient group. CONCLUSIONS: Dermatological consultation is recommended before getting a tattoo, as well as a histopathological examination in case of complications. In patients who develop cutaneous inflammatory reactions following tattooing, additional studies are recommended to investigate systemic diseases such as sarcoidosis, pyoderma gangrenosum, atopic dermatitis, and neoplasms. It is important for physicians to be trained in providing appropriate care in case of complications.

Consenso para el manejo práctico de la urticaria en atención primaria

Introduction: urticaria has a high impact on the quality of life of patients with this condition. While there are multiple evidence-based guidelines, these tend to be aimed at providing management recommendations for specialists rather than primary care physicians, who are usually the first to care for patients with urticaria. Objective: to develop a consensus document aimed at presenting evidence-based recommendations to help general practitioners, family doctors, pediatricians, internists and emergency physicians provide timely care for patients with urticaria, facilitating its diagnosis and timely care, and thus avoiding delays for the patients. Methods: international urticaria guidelines with recommendations based on the GRADE system were used as the source of information. Delegates of the interested scientific societies were convened, and, through structured meetings, treatment barriers and possible solutions for the application of the recommendations in primary care were identified. Results: the main barriers for primary care physicians in applying the guidelines were identified: confusion in the diagnosis, proper timing of treatment, first-line medications, and management of special situations. Possible consensus solutions were proposed for each identified barrier. Conclusion: this consensus document contains recommendations for the management and treatment of acute and chronic urticaria which help primary care physicians provide timely and effective treatment for patients with this disease. (Acta Med Colomb 2022; 48. DOI:https://doi.org/10.36104/amc.2023.2722).

The landscape of vitiligo in Latin America: a call to action.

Vitiligo is a chronic pigmentary condition and severely impacts patient quality of life (QoL). It is an underrecognized burden for patients, healthcare systems, and society in Latin America (LA). This paper examines the journey of a vitiligo patient in LA and assesses the disease landscape. Americas Health Foundation (AHF) assembled a panel of six Argentine, Brazilian, Colombian, and Mexican vitiligo experts. On 10-12 May 2022, they met in a virtual meeting. Each panelist wrote a short paper on barriers to vitiligo diagnosis and treatment in LA before the meeting. AHF staff moderated as the panel reviewed and modified each paper over three days. The panel approved the recommendations based on research, professional opinion, and personal experience. The panel agreed that lack of disease awareness and research, social ostracization, and limited therapeutic options hinder patients in their quest for diagnosis and treatment. In addition to the medical and psychological difficulties associated with vitiligo, problems connected to the Latin American healthcare system may negatively impact diagnosis, prognosis, and treatment. Access to timely diagnosis and treatment is crucial for improving outcomes. Governments, medical societies, academics, patient organizations, industry, and the public must unite to eliminate these challenges.

Alopecia Areata in Latin America: Where are We and Where are We Going?

Alopecia areata (AA) represents an underrecognized burden in Latin America (LA), severely impacting quality of life (QoL). This impact is exacerbated by limited access to specialized dermatologic care and therapies for AA within and among nations. Many of the unmet needs for AA globally also exist in LA. The region has geographic, ethnic, cultural, and economic conditions. With new AA medicines targeting immunologic pathways on the horizon, LA must prepare regarding regulatory issues, reimbursement, awareness, and education to give adequate and timely treatment for patients with AA. To address these issues, the Americas Health Foundation convened a panel of six dermatologists from Argentina, Brazil, Colombia, and Mexico who are experts in AA and its comorbidities for a 3-day virtual meeting to discuss AA diagnosis and treatment in LA and create a manuscript offering recommendations to address discussed barriers. This publication examines unmet AA needs in LA, treatment, and innovative therapies and recommends improving AA care. Access constraints to conventional and novel medicines hinder appropriate treatments for patients. Therapy initiation delays can affect QoL, mental health, and disease progression. People with AA face stigmas, discrimination, and misconceptions owing to a lack of disease awareness. With promising new treatments for AA on the horizon, all stakeholders must coordinate efforts to enhance LA's AA management landscape and improve patient outcomes.

Biobancos: conservación del patrimonio científico de la humanidad

Un biobanco permite mantener en condiciones óptimas y de manera organizada las colecciones de muestras biológicas con los más altos estándares de calidad, éticos y legales, con fines de investigación biomédica que genere nuevo conocimiento, así como aplicaciones de docencia. Los avances en biomedicina y el desarrollo de tecnologías, han facilitado el acceso a la información y esto debe aplicarse en pro de un mejor aprovechamiento de las muestras biológicas, en la comprensión de las bases inmunopatogénicas de las enfermedades, que finalmente lleve a proponer estrategias de detección, prevención, promoción y tratamiento. El Laboratorio de Dermatopatología de la Sección de Dermatología de la Facultad de Medicina de la Universidad de Antioquia, ha procesado más de 57.000 biopsias desde su fundación, conservando los archivos clínicos, registros fotográficos, placas y bloques histopatológicos, otorgándole un gran potencial como biobanco. Esta revisión narrativa de la literatura tiene como objetivo ilustrar una visión general de la importancia del desarrollo de los biobancos, así como los aspectos a tener en cuenta en su estructuración.

Summary A biobank allows the collections of biological samples to be maintained in optimal conditions and in an organized manner with the highest quality, ethical and legal standards, for biomedical research purposes that generate new knowledge, as well as teaching applications. Advances in biomedicine and the development of technologies have facilitated access to information and this should comply in favor of a better use of biological samples in the understanding of the immunopathogenic bases of diseases, which finally carry out a proposing strategies of detection, prevention, promotion and treatment. The Dermatopathology Laboratory of the Dermatology Section of the Faculty of Medicine of the University of Antioquia has processed more than 57,000 biopsies since its foundation, preserving the clinical files, photographic records, plates and histopathological blocks, giving it great potential as a biobank. This narrative review of the literature aims to illustrate an overview of the importance of the development of biobanks, as well as the aspects to take into account in their structuring.

COVID-19: perspectivas terapéuticas en IL-17/Th17 / COVID-19: a perspective focus on IL-17/Th17

RESUMEN Las células T helper-17 (Th17) y la interleuquina (IL) IL-17 desempeñan funciones biológicas relacionadas con la protección contra infecciones por bacterias extracelulares y hongos. En algunas enfermedades inflamatorias y autoinmunes hay una secreción persistente y estas participan en su patogénesis. Recientemente, se ha postulado la participación de las respuestas IL-17/Th17 en la patogénesis de la enfermedad por coronavirus 2019 (COVID-19). El objetivo de esta revisión es resumir la evidencia del papel de la IL-17/Th17 en la inmunopatogénesis del COVID-19, como sustento de la possible utilización de los inhibidores de IL-17 en el manejo terapéutico de esta infección.

SUMMARY Interleukin 17 (IL-17)-producing helper T cells (Th17) and IL-17 play an important role in the defense against extracellular bacteria and fungi; however, persistent secretion of IL-17 is also an important component in the pathogenesis of many inflammatory and autoimmune diseases. Recent evidence suggests that Th17 cells and IL-17 are also involved in the immunopathogenesis of COVID-19. This review summarizes the evidence related with the role of Th17/IL-17 in severe COVID-19, which support the possible use of IL-17/IL-17R inhibitors in the treatment of this infection.

Presence of IgE Autoantibodies Against Eosinophil Peroxidase and Eosinophil Cationic Protein in Severe Chronic Spontaneous Urticaria and Atopic Dermatitis.

PURPOSE: Eosinophils are frequently found in atopic dermatitis (AD) and chronic spontaneous urticaria (CSU) that release eosinophil peroxidase (EPX) and eosinophil cationic protein (ECP). Continuous exposure to these proteins could trigger an autoimmune response which may contribute to the pathogenesis and severity of skin inflammation. In this study, we investigate the immunoglobulin E (IgE) response against eosinophil proteins in CSU and AD. METHODS: We recruited patients with severe AD, severe CSU and healthy subjects to explore the presence of IgE autoantibodies and cross-reactivity against EPX, ECP and thyroid peroxidase (TPO). The potential cross-reactive epitopes among the peroxidase family were determined using in silico tools. RESULTS: The frequencies of anti-EPX IgE (28.8%) and anti-ECP IgE (26.6%) were higher in the AD group, and anti-TPO IgE was higher in the CSU group (27.2%). In the CSU group, there was a correlation between the anti-EPX IgE and anti-TPO IgE levels (r = 0.542, P < 0.001); TPO inhibited 42% of IgE binding to EPX, while EPX inhibited 59% of IgE binding to TPO, suggesting a cross-reactivity with EPX as a primary sensitizer. There was greater inhibition when we used a pool of sera CSU and AD, TPO inhibited 52% of IgE binding to EPX, while EPX inhibited 78% of IgE binding to TPO. In silico analysis showed a possible shared epitope in the peroxidase protein family. CONCLUSIONS: IgE against eosinophil proteins may contribute to chronic inflammation in patients with AD and CSU. Cross-reactivity between EPX and TPO could explain thyroid problems in CSU patients.

Cell signaling in cutaneous T-cell lymphoma microenvironment: promising targets for molecular-specific treatment.

Cutaneous T-cell lymphomas (CTCL) result from the infiltration and proliferation of a population of T cells in the skin, inducing changes in the activity of both T cells and surrounding skin cells. In the CTCL microenvironment, cell interactions mediated by cell signaling pathways are altered. Defining changes in cell signaling enables to understand T-cell deregulations in the CTCL microenvironment and thus the progression of the disease. Moreover, characterizing signaling networks activated in CTCL stages can lead to consider new molecular biomarkers and therapeutic targets. Focusing on mycosis fungoides (MF), the most frequent variant of CTCL, and Sézary syndrome (SS), its leukemic variant, this review highlights recent molecular and genetic findings revealing modifications of key signaling pathways involved in (1) cell proliferation, cell growth, and cell survival such as MAP kinases and PI3K/Akt; (2) immune responses derived from TCR, TLR, JAK/STAT, and NF-kB; and (3) changes in tissue conditions such as extracellular matrix remodeling, hypoxia, and angiogenesis. Alterations in these signaling networks promote malignant T-cell proliferation and survival, T-cell migration, inflammation, and suppression of immune regulation of malignant T cells, making a skin microenvironment that allows disease progression. Targeting key proteins of these signaling pathways, using molecules already available and used in research, in clinical trials, and with other disease indications, can open the way to different therapeutic options in CTCL treatment.

Pyoderma gangrenosum associated to the use of cocaine/levamisole. Series of three cases and literature review

Abstract Pyoderma gangrenosum associated to the use of cocaine/levamisole is a rare condition associated to their consumption. Cocaine use is frequent in Colombia, and the substance is contaminated with levamisole, an anthelmintic that increases the psychotropic effects and enhances its side effects. We present three clinical cases of patients with ulcerated lesions, in which the diagnosis was pyoderma gangrenosum secondary to the use of cocaine contaminated with levamisole. This called the attention of the health staff to investigate the abuse of substances in gangrenous pyoderma and also evidence that the interruption of consumption was the basis of management.

Pyoderma gangrenosum associated to the use of cocaine/levamisole. Series of three cases and literature review.

Pyoderma gangrenosum associated to the use of cocaine/levamisole is a rare condition associated to their consumption. Cocaine use is frequent in Colombia, and the substance is contaminated with levamisole, an anthelmintic that increases the psychotropic effects and enhances its side effects. We present three clinical cases of patients with ulcerated lesions, in which the diagnosis was pyoderma gangrenosum secondary to the use of cocaine contaminated with levamisole. This called the attention of the health staff to investigate the abuse of substances in gangrenous pyoderma and also evidence that the interruption of consumption was the basis of management.

Enfoque del paciente con adenopatías generalizadas. Importancia de la estrategia didáctica del estudio de casos clínicos: a propósito de un paciente con linfoma de Hodgkin asociado a una infección por el virus de Epstein-Barr

Se muestra el caso de un paciente con 56 años de edad, con un síndrome adenomegálico generalizado que presentó un linfoma de Hodgkin de celularidad mixta, asociado al virus de Epstein-Barr. El paciente previo al inicio del linfoma presentó episodios prolongados de estrés emocional, lo que posiblemente contribuyó a la disminución de la vigilancia inmunológica. El caso fue abordado por los estudiantes de quinto semestre en la asignatura Acto médico, una estrategia didáctica interdisciplinaria. Este artículo presenta los aspectos a tener en cuenta en el enfoque clínico de los pacientes con adenopatías desde una perspectiva integradora de la inmunología, la clínica y los diagnósticos diferenciales. Se resalta el valor del estudio de los casos clínicos con varios métodos diagnósticos como estrategia didáctica. Finalmente, se realiza una revisión de la literatura sobre el linfoma Hodgkin orientada al papel en el que participa la infección por el virus de Epstein-Barr, relacionada con la inmunosupresión por estrés.

SUMMARY We present the case of a 56-year-old patient with a generalized adenomegalic syndrome who presented a mixed cellular Hodgkin's lymphoma associated with Epstein Barr Virus. The patient had had great emotional stress prior to the onset of lymphoma, which possibly contributed to the decrease in immunological surveillance. The case was addressed by the students of the fifth semester in the subject "Medical Act", an interdisciplinary didactic strategy. We present the aspects to be taken into account in the approach of the clinician of patients with adenopathies from an integrative perspective of immunology, clinical and differential diagnoses; and the value of the study of clinical cases with several diagnostic approaches as a didactic strategy is highlighted. Finally, we present a literature review about Hodgkin lymphoma and the role which plays stress related Epstein Barr Virus infection.

Chronic pruritus. / Prurito crónico.

Chronic pruritus is defined as an unpleasant sensation on the skin that causes scratching and lasts more than six weeks. This symptom may be a manifestation of a cutaneous or systemic disease and it jeopardizes the patients' quality of life, constantly altering their sleep and daily activities. The pathophysiology is complex and it includes multiple mediators and their respective receptors which, through different signaling pathways, carry information through type C nerve fibers towards the thalamus; from where it is distributed to various areas of the cerebral cortex. The understanding of these mechanisms has made it possible to identify potential therapeutic targets and the development of molecules that are increasingly more effective and safer for patients. The present review aims to give a vision of the diagnostic and therapeutic handling of patients with chronic pruritus.

El prurito crónico se define como una sensación no placentera de la piel que induce el rascado y que dura más de seis semanas. Este síntoma puede ser la manifestación de una enfermedad cutánea o sistémica y compromete la calidad de vida de los pacientes, alterando de forma consistente el sueño y las actividades diarias. La fisiopatología es compleja e incluye múltiples mediadores y sus respectivos receptores, que a través de diferentes vías de señalización llevan información por las fibras nerviosas tipo C hacia el tálamo, desde donde se distribuye a diversas zonas de la corteza cerebral. La comprensión de estos mecanismos ha permitido identificar posibles blancos terapéuticos y el desarrollo de moléculas cada vez más efectivas y seguras para los pacientes. La presente revisión pretende dar una visión acerca del manejo diagnóstico y terapéutico de los pacientes con prurito crónico.

Reporte de la experiencia de la Sección de Dermatología de la Universidad de Antioquia en la quinta jornada de detección de cáncer de piel, Asocolderma 2016 / Report of the experience of the Section of Dermatology of the University of Antioquia, Medellin, in the fifth working day of detection of skin cancer, Asocolderma 2016

RESUMEN Introducción: las jornadas de detección de cáncer de piel son una herramienta para la educación e identificación temprana de individuos afectados. Se presentan los resultados de la participación de la Sección de Dermatología de la Universidad de Antioquia en la quinta jornada de la Asociación Colombiana de Dermatología y Cirugía Dermatológica, realizada el 25 y 26 de agosto de 2016. Métodos: pacientes mayores de 18 años y menores con consentimiento de los padres. Se realizó evaluación clínica de toda la piel y análisis histopatológico de las lesiones sospechosas de cáncer de piel, previo consentimiento informado por escrito. Resultados: se adjudicaron 132 consultas y de los asistentes 33 tuvieron lesiones sospechosas de malignidad, a 22 se les tomó biopsia y a 11 se les hizo diagnóstico clínico, de estos, 9 con queratosis actínicas, 1 con nevus atípico y otro paciente con ambos diagnósticos. En 11 pacientes se diagnosticó cáncer de piel, uno de ellos con 2 melanomas malignos, 1 con carcinoma escamocelular y 9 con carcinoma basocelular. Discusión: la cuarta parte de los asistentes presentaron lesiones sospechosas de malignidad. El carcinoma basocelular fue el tipo de cáncer más frecuente, 6,06 %, seguido por el carcinoma espinocelular 0,75 % y el melanoma maligno 0,75 %. Preocupan los comportamientos de riesgo de exposición solar; de los pacientes con lesiones premalignas o malignas, el 40,6 % refirió quemaduras solares antes de los 18 años y el 48,5% practicaban actividades al sol. Predominan los fototipos II y III en el 83,4 %, lo que aumenta el riesgo de cáncer de piel.

SUMMARY Introduction: Skin cancer screening days are a tool for the early identification and education of affected individuals. We present the results of the participation of the Dermatology Service of the University of Antioquia on the fifth campaign of the Colombian Association of Dermatology and Dermatologic Surgery, held on August 25 and 26, 2016. Methods: Patients Older than 18 years and minors with parental consent. We performed clinical evaluation of total body skin and histopathological analysis of suspected skin cancer lesions, with prior written informed consent. Results: A total of 132 patients were attended, 33 were suspected lesions, 22 were biopsied, 9 underwent clinical diagnosis of actinic keratoses, 1 atypical nevus and 1 both diagnosis. In 11 patients skin cancer was diagnosed, one with two malignant melanomas, one with squamous cell carcinoma and nine with basal cell carcinoma. Discussion: 25 % of the attendees presented suspicious injuries. Basal cell carcinoma was the most common type of cancer, 6.06 %, followed by squamous cell carcinoma 0.75 % and malignant melanoma 0.75 %. Concern about risk behavior of sun exposure; of patients with premalignant or malignant lesions, 40.6 % reported sunburn before age 18 and 48.5% practiced activities in the sun. Phototypes II and III predominate in 83.4 %, which increases the risk of skin cáncer

TRAPS, síndrome periódico asociado al receptor de necrosis tumoral: inmunopatogénesis y enfoque clínico / Understanding the immunopathogenic bases and the clinical approach of the periodic syndrome associated with the tumor necrosis receptor, TRAPS

RESUMEN El síndrome periódico asociado al receptor del factor de necrosis tumoral (TRAPS), se caracteriza por episodios de fiebre de más de 10 días de duración, mialgias migratorias, pseudocelulitis, dolor abdominal y edema bipalpebral. Su principal complicación es la amiloidosis y la falla renal producida por el estado inflamatorio crónico. Es una enfermedad autosómica dominante por mutación en el gen TNFRSF1A que codifica el receptor 1 del factor de necrosis tumoral (TNF). En las hipótesis elaboradas para explicar la enfermedad se describen la alteración en la liberación del receptor de TNF mutado, la activación del factor nuclear potenciador de las cadenas ligeras kappa de las células B activadas (NFkB) de forma independiente, las proteínas mal plegadas y alteraciones en el tráfico del receptor mutado, llevando a la acumulación de especies reactivas del oxígeno y defectos en la muerte celular por autofagia y apoptosis. Se han dirigido muchos esfuerzos en descubrir las bases inmunopatogénicas del TRAPS, dificultado por el elevado número de mutaciones encontradas, que se traducen en diferentes mecanismos y formas de presentación de la enfermedad. El tratamiento se basa en el bloqueo del TNF y de la interleuquina-1 (IL-1), la mejor comprensión de la inmunopatogénesis podría permitir un mejor seguimiento de los pacientes y el empleo de otras terapias.

SUMMARY Tumor necrosis factor receptor periodic syndrome (TRAPS) is characterized by episodes of fever of more than 10 days of duration, migratory myalgias, pseudocellulitis, abdominal pain and bipalpebral edema. It´s main complication is amyloidosis and renal failure caused by the chronic inflammatory state. It is an autosomal dominant disease, by mutation in the TNFRSF1A gene encoding tumor necrosis factor (TNF) receptor 1. Among the hypotheses to explain the disease have been proposed the alteration in the release of the mutated TNF receptor; the activation of nuclear factor enhancer of the kappa light chains of independently activated B cells (NFkB); poorly folded proteins, and alterations in the traffic of the mutated receptor. All of them, leading to the accumulation of reactive oxygen species and defects in cell death by autophagy and apoptosis. Many efforts have been directed to discover the immunopathogenic bases of TRAPS, which has been hampered by the high number of mutations found, which translate different mechanisms and forms of presentation of the disease. The treatment is based on the blockade of TNF and interleukin-1 (IL-1). The better understanding of immunopathogenesis could allow better monitoring of patients and the use of other therapies.

Implementación de la gestión de riesgo en los procesos misionales de la Sección de Dermatología de la Universidad de Antioquia (Medellín, Colombia) siguiendo las directrices de la norma ISO 9001: 2015 / Implementation of Risk Management in the Mission Processes of the Dermatology Section of the Universidad de Antioquia (Medellín, Colombia) Following the ISO 9001: 2015 Guidelines / Implementação de gestão de risco em processos missionais da Seção de Dermatologia da Universidade de Antioquia (Medellín, Colômbia) seguindo diretrizes da norma ISO 9001: 2015

Resumen La gestión de riesgos en los servicios de atención en salud es un proceso que considera la planeación y aplicación de estrategias orientadas a controlar posibles efectos adversos que surjan durante la atención a los usuarios, la calidad en el servicio y la seguridad del paciente. En el presente artículo se reporta el desarrollo del sistema de gestión del riesgo de los procesos misionales de la Sección de Dermatología de la Universidad de Antioquia, así como los principales resultados obtenidos a la fecha y la manera como el Sistema de Gestión de Calidad bajo la norma ISO 9001 sirvió de complemento y apoyo al sistema de gestión del riesgo implementado. Se identificaron cinco riesgos inherentes para el Laboratorio de Dermatopatología, seis para Otros Procesos Dermatológicos y ocho para la Unidad de Fotodermatología, los cuales fueron analizados y evaluados, luego de lo cual se implementaron los controles pertinentes.

Abstract Risk management in health care services is a process that takes into account the planning and implementation of strategies aimed at controlling possible adverse effects that arise during the attention to users, quality of service, and patient safety. This article reports on the development of the risk management system for the mission processes of the Dermatology Section of the Universidad de Antioquia, as well as on the main results obtained to date and the way in which the Quality Management System (under the ISO 9001 standard) worked as a complement and support to the implemented risk management system. Five inherent risks were identified for the Dermatopathology Laboratory, six for Other Dermatological Procedures, and eight for the Photodermatology Unit, all of which were analyzed and evaluated; the relevant controls were implemented afterwards.

Resumo A gestão de riscos nos serviços de atenção em saúde é um processo que considera o planejamento e aplicação de estratégias orientadas a controlar possíveis efeitos adversos que surgirem durante o atendimento a utentes, a qualidade no serviço e a segurança do paciente. No presente artigo relata-se o desenvolvimento do sistema de gestão de riscos dos processos missionais da Seção de Dermatologia da Universidade de Antioquia, bem como os principais resultados obtidos a hoje e a maneira como o Sistema de Gestão de Qualidade sob a norma ISO 9001 serviu de complemento e apoio ao sistema de gestão do risco implementado. Cinco riscos inerentes ao Laboratório de Dermatopatologia foram identificados, seis para outros Processos Dermatológicos e oito para a Unidade de Fotodermatologia, os quais foram analisados e avaliados, após disso implementaram-se os controles pertinentes.

Aspectos inmunogenéticos de la psoriasis con énfasis en micro-ARN / Immunogenetic aspects of psoriasis with emphasis on micro-RNA

La psoriasis es una enfermedad inflamatoria crónica de la piel, de origen autoinmune, en la que diferentes poblaciones de linfocitos T ayudadores (Th1 y Th17), así como los queratinocitos y las citocinas que producen estas poblaciones celulares han sido implicadas en la etiopatología de la enfermedad.Los mecanismos de regulación epigenéticos son el puente de unión entre la exposición ambiental y los factores genéticos. Actualmente se sabe que los denominados micro-ARN (mi-ARN), ARN no codificantes de cadena simple, participan activamente en la regulación epigenética. Alteraciones en la expresión de miR-125b, miR-424, miR-21 y miR-203, entre otros, han sido implicados en diferentes aspectos de la enfermedad. Estudios globales de la expresión de mi-ARN, tanto por micromatrices como por secuenciamiento directo de ARN, han revelado importantes diferencias en la expresión de mi-ARN en piel de individuos normales y psoriáticos. Estos mi-ARN pueden ser considerados como posibles blancos terapéuticos o biomarcadores de enfermedad (AU)

Psoriasis is a chronic inflammatory disease of the skin, of autoimmune origin, with different cells implicated in the aetiopathology, such as T helper lymphocytes (Th1 and Th17), keratinocytes, and cytokines produced by these cells. The epigenetic regulatory mechanisms are the junction between environmental exposure and genetic factors. It is known that microRNAs (miRNAs), single chain RNAs, are actively involved in epigenetic regulation. Alterations in the miR-125b, miR-424, miR- 21 and miR-203 expression, and others, have been involved in different aspects of the disease. Global studies of miRNA expression performed using microarrays and by direct RNA sequencing revealed important differences in miRNA expression in normal skin and psoriatic individuals. These miRNAs can be considered as potential therapeutic targets or biomarkers of disease (AU)

Elementos clave de la inmunogenética de la psoriasis: A review / Key elements of psoriasis immunogenetics / Elementos importantes da imunogenética da psoríase

La psoriasis, que afecta de 2% a 3% de la población mundial, es una de las enfermedades cutáneas más frecuentes, Se presenta en cualquier etapa de la vida. La psoriasis tipo I o temprana comienza antes de los 40 años en tanto que la tipo II es de inicio tardío, luego de los 40 años. Tiene una fuerte base genética y la probabilidad de heredarla cuando los dos padres están afectados es hasta del 50%. Se han descrito diferentes regiones de susceptibilidad asociadas a la psoriasis, que se denominan PSORS, de las que PSORS-1 es la más frecuente. PSORS-1 está en el cromosoma 6 en el que se localiza el HLA-Cw6, que es el gen hasta ahora más relacionado con la psoriasis. La función de HLA-Cw6 en la psoriasis no está completamente entendida, pero se ha asociado con la psoriasis tipo I, la psoriasis en gotas y la presentación antigénica de una gama de antígenos entre los que se encuentran los derivados de Streptococcus pyogenes. Por otra parte, algunos polimorfismos de nucleótido simple en genes que codifican para citocinas como IL-12, IL-23, TNF-α o sus receptores, se han relacionado con la inmunopatogénesis de esta enfermedad.

Psoriasis is one of the most common skin diseases, affecting 2% to 3% of the world population. It occurs at any stage of life. ''Early'' psoriasis or type I manifests before 40 years, and ''late'' psoriasis or type II, after 40 years. It has a strong genetic basis and the probability of inheriting the disease when both parents are affected is up to 50%. Different susceptibility regions associated with psoriasis, called PSORS, have been described, PSORS-1 being the most frequent one. It is in chromosome 6 and in this region HLA-Cw6 is located, which is until now the gene more associated with psoriasis. The role of HLA-Cw6 in psoriasis is not fully understood, but it has a relationship with type I psoriasis, guttate psoriasis and the presentation of an array of antigens including those derived from Streptococcus pyogenes. Furthermore, some single nucleotide polymorphisms in genes encoding cytokines such as IL-12, IL-23, TNF-α or their receptors are associated with the immunopathogenesis of the disease.

A psoríase, que afeta de 2% a 3% da população mundial, é uma das doenças cutâneas mais frequentes, Apresenta-se em qualquer etapa da vida. A psoríase tipo I ou precoce começa antes dos 40 anos enquanto a tipo II é de início tardio, depois dos 40 anos. Tem uma forte base genética e a probabilidade de herdá-la quando os dois pais estão afetados é até de 50%. Descreveram-se diferentes regiões de susceptibilidade associadas à psoríase, que se denominam PSORS, das que PSORS-1 é a mais frequente. PSORS-1 está no cromossomo 6 no que se localiza o HLA-Cw6, que é o gene até agora mais relacionado com a psoríase. A função de HLA-Cw6 na psoríase não está completamente entendida, mas se associou com a psoríase tipo I, a psoríase em gotas e a apresentação antigénica de uma gama de antígenos entre os que se encontram os derivados de Streptococcus pyogenes. Por outra parte, alguns polimorfismos de nucleótido simples em genes que codificam para citocinas como IL-12, IL-23, TNF-α ou seus receptores, relacionaram-se com a imunopatogênese desta doença.

Arginina y cáncer: implicaciones en la regulación de la respuesta antitumoral / Arginine and cancer: Implications in the regulation of antitumoral response

Los informes de la literatura apoyan el papel de la arginina como mecanismo regulador de la respuesta inmune. Se ha descrito la correlación entre disminución de la arginina y reducción de la proliferación y la activación de los linfocitos T en trasplante hepático, trauma grave, sepsis y cáncer. Entre los efectos se describen la disminución en la expresión de la cadena CD3z (traducción de la señal de activación en el linfocito T). La disminución de la arginina está relacionada con la producción de arginasa 1 (ARG1) por parte de las células mieloides supresoras. Se han propuesto dos posibles mecanismos por medio de los cuales el aumento de la actividad de ARG1 podría estar actuando en un proceso tumoral. El primero es la disminución de la proliferación de los linfocitos y el freno del ciclo celular. El segundo es promover el crecimiento tumoral al transformar la arginina en precursores de poliaminas. Se presentan en este artículo los principales conceptos del papel de la arginina en la respuesta antitumoral.

Recent findings support the potential role of arginine as a regulator of the immune response. Correlation between decreased arginine and decreased proliferation and activation of T lymphocytes has been described in liver transplantation, severe trauma, sepsis and cancer. Among the effects, decrease in the CD3z chain expression (activation signal in the T cell) has been described. Arginine is reduced in relation to the production of arginase 1 (ARG1) by myeloid suppressor cells. Two possible mechanisms have been postulated by which the increased activity of ARG1 could be acting on a tumor. The first is the reduction of lymphocyte proliferation and cell cycle arrest. The second is to promote tumor growth by transforming arginine in precursors of polyamines. We present in this article the main concepts on the role of arginine in antitumor response.

Linfoma cutáneo de células T Revisión del tema con énfasis en la inmunopatogénesis / Cutaneous T-cell lymphoma: Review with emphasis on immunophatogenesis

Bajo el término linfoma cutáneo de células T (LCCT) se agrupa una serie de enfermedades que tienen en común la presencia de un clon maligno de células T y la afectación de la piel. La micosis fungoide (MF) es la forma más común de LCCT, seguida por el síndrome de Sèzary (SS). La causa definitiva de la MF es desconocida. El inmunofenotipo de la mayoría de los casos de MF es de células T de memoria CD3+CD4+CD45RO+CLA+CD8-. Los linfocitos T CD4+ malignos migran hasta la epidermis y se localizan alrededor de las células de Langerhans (LC). En el SS las células pierden el epidermotropismo e infiltran extensamente la dermis, la sangre y otros tejidos; estas células presentan un inmunofenotipo predominante de células T neoplásicas CD3+CD4+CD8-CD7-CD26- CD158k+CD94-. El perfil Th2 y la supresión de respuestas Th1 son dos factores críticos en la progresión de la enfermedad. Se han evaluado muy poco las alteraciones en la regulación inmune en el LCCT. Un mejor entendimiento de la función de las células T y de la inmunobiología de los LCCT permitiría mejorar el pronóstico, el tratamiento y el seguimiento de los pacientes con estas neoplasias.

The term cutaneous T-cell lymphoma (CTCL) refers to several diseases that have in common the presence of a malignant T-cell clone with involvement of the skin. Mycosis fungoides (MF) is the most common form of CTCL, followed by the Sèzary syndrome (SS). The cause of mycosis fungoides is unknown. Immunophenotype of most cases of MF is made up by memory T cells CD3+CD4+CD45RO+CLA+CD8-. Malignant T CD4+ lymphocytes migrate to the epidermis and localize around Langerhans cells. In SS, cells loose their epidermotropism and extensively infiltrate the dermis, blood and other tissues. These cells present a predominant immunophenotype of neoplasic T cells CD3+CD4+CD8-CD7-CD26-CD158k+CD94-. The Th2 profile and the supression of Th1 responses are two critical factors in the progression of the disease. Alterations in the immune regulation in CTCL have not been thoroughly evaluated. A better understanding of T-cell function and of the immunobiology of CTCL would allow to improve the prognosis, therapy and follow-up of patients with these neoplasias.