Results and analysis of an intercomparisons study for individual monitoring services of Latin American and Caribbean regions.

The aim of this paper is to present the results obtained by the Latin-American and Caribbean personal dosimetry services that participated, with the support of IAEA, in the 2020-Eurados whole-body dosemeter intercomparison for photon radiation. All participant services in this study use thermoluminescent dosimetry (TLD) systems except one that uses optically stimulated luminescence (OSL) dosemeters. Data analysis shows that 93.4% of the results are within the acceptance range, according to International ISO Standard ISO 14146: 2018. The evaluation of the trumpet curves shows that only three laboratories presented a few dosemeters results outside the limits of acceptability. Participation in this Eurados intercomparison exercise gave the Latin American and Caribbean laboratories the opportunity to show compliance with their own quality management system, to compare results with other participants and to develop plans for improving their dosimetry systems. It also gave the assurance that occupational doses are being measured properly and following the international standards in the regions.

McKittrick Wheelock syndrome secondary to adenocarcinoma of the rectum: case report and diagnostic considerations

Introduction: McKittrick-Wheelock syndrome is a rare entity characterized by chronic diarrhea, acute kidney injury, and hydroelectrolytic imbalance associated with a large rectal tumor, frequently a villous adenoma. Case report: A 69-year-old male with chronic diarrhea with mucus. He underwent a colonoscopy with biopsies, reporting adenocarcinoma of the rectum in situ, and underwent a robot assisted intersphincteric resection with colo-anal anastomosis and a protecitive ileostomy. Discussion: Described in 1954, this syndrome is manifested by electrolyte imbalance and acute renal injury secondary to diarrhea associated with a rectal villous adenoma, often with long lasting symptoms. The most frequent symptom being watery diarrhea with mucus. The definitive treatment consists of surgical resection. Conclusion: Although this is a rare pathology, it should be considered as a differential diagnosis in cases of chronic diarrhea associated with water and electrolyte disorders. (AU)

Symbiotic Supplementation (E. faecium and Agave Inulin) Improves Spatial Memory and Increases Plasticity in the Hippocampus of Obese Rats: A Proof-of-Concept Study.

Obesity has been linked to cognitive impairment through systemic low-grade inflammation. High fat and sugar diets (HFSDs) also induce systemic inflammation, either by induced Toll-like receptor 4 response, or by causing dysbiosis. This study aimed to evaluate the effect of symbiotics supplementation on spatial and working memory, butyrate concentration, neurogenesis, and electrophysiological recovery of HFSD-fed rats. In a first experiment, Sprague-Dawley male rats were given HFSD for 10 weeks, after which they were randomized into 2 groups (n = 10 per group): water (control), or Enterococcus faecium + inulin (symbiotic) administration, for 5 weeks. In the fifth week, spatial and working memory was analyzed through the Morris Water Maze (MWM) and Eight-Arm Radial Maze (RAM) tests, respectively, with 1 week apart between tests. At the end of the study, butyrate levels from feces and neurogenesis at hippocampus were determined. In a second experiment with similar characteristics, the hippocampus was extracted to perform electrophysiological studies. Symbiotic-supplemented rats showed a significantly better memory, butyrate concentrations, and neurogenesis. This group also presented an increased firing frequency in hippocampal neurons [and a larger N-methyl-d-aspartate (NMDA)/α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) current ratio] suggesting an increase in NMDA receptors, which in turn is associated with an enhancement in long-term potentiation and synaptic plasticity. Therefore, our results suggest that symbiotics could restore obesity-related memory impairment and promote synaptic plasticity.

Perianal psoriasis as the first manifestation of the disease

Introduction: Inverse psoriasis affects the skin of flexural areas, such as the groin, axillae, umbilicus, intergluteal fold, and external genitalia. Clinical Case: We herein report the case of a man who presented with anal pruritus and, upon physical examination, a perianal dermatosis was found, which was characterized by erythematous plaques, with fine scaling. The case was initially managed with zinc oxide, and when no improvement was observed, we decided to take an incisional biopsy, which indicated histological changes suggestive of psoriasiform dermatitis. Discussion: Inverse psoriasis affects 3% to 7% of patients with psoriasis, and it manifests with erythematous plaques without the classic scaling appearance. The skin in these areas is susceptible to maceration, irritation, and ulceration, which alter the classic clinical picture. It may present with typical lesions or, less frequently, in isolation in the anogenital region. In the anogenital presentation only, the diagnosis should be made by biopsy, looking for the classic histopathological features of psoriasis. As for the first-line treatment, low- or medium-potency topical steroids are used for short periods of time; the second-line treatment is with emollients and tar-based products; and the third-line treatment uses an immunomodulator. Conclusion: This presentation is infrequent, and it requires a high index of suspicion for the diagnosis, always supported by biopsies, in search of the classic histopathological features of psoriasis. (AU)

Colitis por cytomegalovirus en trasplante renal: Presentación de 2 casos / Cytomegalovirus colitis in kidney transplant recipients: presentation of two cases

Resumen La infección por citomegalovirus (CMV) es un riesgo latente en pacientes inmunocomprometidos por trasplante renal, asociándose con aumento del riesgo de rechazo del injerto y muerte. La infección por CMV puede manifestarse como infección activa o enfermedad por CMV (dividida en síndrome por CMV y enfermedad tisular invasiva por CMV). Presentamos dos casos de enfermedad tisular invasiva por CMV, la cual se presentó entre los primeros siete meses posteriores al trasplante. Ambos casos eran D+/R-; recibieron agentes depletores de linfocitos y micofenolato y profilaxis para CMV de acuerdo con las guías de práctica clínica. Los criterios para enfermedad por CMV incluyeron replicación viral detectable en sangre, hallazgos endoscópicos clásicos y confirmación histopatológica. Hacemos énfasis en la necesidad de identificar los factores de riesgo para la infección por CMV en pacientes con trasplante renal, especialmente el seroestatus donador/receptor y los medicamentos inmunosupresores. Aun cuando las guías de práctica clínica sugieren de uno a tres meses de profilaxis para CMV en casos de alto riesgo, debería considerarse la profilaxis extendida y el ajuste de los medicamentos inmunosupresores.

Abstract Cytomegalovirus infection is a latent risk among immunocompromised kidney transplant recipients and is associated with increased risk of allograft failure and death. CMV infection can manifest as active infection or as CMV disease (divided in CMV syndrome and CMV tissue-invasive disease). We present two cases of tissue invasive CMV disease, presenting within 7 months after kidney transplantation. Both cases were D+/R-, received lymphocyte-depleting agents and mycophenolate, and both received CMV prophylaxis according to General Practice Guidelines. CMV disease criteria included detectable viral replication in blood, classical endoscopic findings and histopathological confirmation. We emphasize the need of categorical identification of CMV infection risk factors among kidney transplantation recipients, specially CMV donor/recipient serostatus and immunosuppressive medication. Although clinical practice guidelines suggest 1 to 3 months CMV prophylaxis in high-risk cases, extended prophylaxis and immunosuppressive medication adjustment should be considered.

Effects of Dietary Components During and After Concomitant Chemoradiotherapy, Radiotherapy, or Sequential Chemoradiotherapy to the Abdominopelvic Area.

Radiotherapy is a fundamental part of the treatment of pelvic neoplasms. Up to 90% of patients develop gastrointestinal symptoms as a result of acute injury to the small and large intestine, particularly in the mucosa. Radiotherapy leads to atrophy of the intestinal epithelium, acute crypt inflammation, inflammatory infiltration of the epithelium, malabsorption of lactose, and biliary salts as well as alterations in pancreatic enzymes and biliary salts, resulting in the malabsorption syndrome and dysbiosis. The most commonly reported symptoms of pelvic radiation disease include changes in bowel habits (94%), decreased fecal consistency (80%), frequency of bowel movements (74%), bowel urgency (39%), and fecal incontinence (37%). Although nutritional interventions with dietary modifications have been reported to prevent and treat gastrointestinal symptoms, the evidence remains inconclusive.

Conflictos socioambientales: entre la legitimidad normativa y las legitimidades sociales. caso mina la colosa, cajamarca (tolima, colombia) / Socio-environmental conflicts: between normative legitimacy, and social legitimacies. the colosa mine in cajamarca tolima, colombia) case study

El presente artículo tiene como marco de análisis la descripción de un conflicto socioambiental, presentado en razón del proyecto minero adelantado en la mina La Colosa del municipio de Cajamarca (Tolima) en Colombia. En primer lugar, se conceptualiza sobre las diferentes posiciones teóricas del conflicto socioambiental a partir de teorías jurídicas, sociales y ambientales. Se analizan las diferentes dimensiones sociales, económicas y políticas del conflicto y se puntualiza en la descripción del caso objeto de estudio. En segundo lugar, se problematiza en torno a la legitimidad de las normas y las legitimidades sociales, a partir de lo analizado en el caso estudiado. Por último, se concluye que el alcance de la legitimidad perseguido por las normas y por la institucionalidad representada en el Estado no se agota en el simple cumplimiento de las normas. La legitimidad se materializa a través de la aceptación por parte de los asociados y de su correspondencia con las percepciones sociales

The description of a socio-environmental conflict serves as the analytical framework of this article. It is a mining project carried out in The Colosa Mine located in the municipality of Cajamarca (Tolima) in Colombia. First, the different theoretical positions concerning the socio-environmental conflict from legal, social and environmental theories are conceptualized. Different social, economic and political dimensions of the conflict are also analyzed focusing on the description of the case under study. Secondly, relevant problematic issues about the legitimacy of certain norms and social legitimacies emerge from the analyzed case study. Finally, it is concluded that the scope of the legitimacy pursued by the rules as well as the institutional aspects representing the State go beyond the simple compliance of the norms. Legitimacy is achieved through the acceptance on the part of the partners and its correspondence with social perceptions

Efecto de una intervención cognoscitivo conductual para el manejo de los celos en la relación de pareja / Effect of a cognitive behavioral intervention for jealousy management in couple relationships

Resumen El objetivo de este estudio fue reducir los niveles de celos en seis mujeres, estudiantes universitarias, con edades entre los 18 y 35 años de edad, que presentaban celos patológicos. El proceso terapéutico utilizado se basó en la guía de intervención cognitivo comportamental para el manejo de los celos en la relación de pareja. La intervención tuvo una duración de dos meses y se desarrolló en siete sesiones, bajo un diseño AB y con seguimiento a los 6 meses a dos de las consultantes. Los resultados muestran una disminución en el puntaje de la Escala Interpersonal de Celos. Se encontraron diferencias significativas en los resultados globales de la escala en la aplicación pre y pos test (p<,05), así como en la frecuencia de conductas asociadas al problema. Se discuten las bondades y limitaciones de la intervención.

Abstract The aim of this study was to reduce the level of jealousy in six female college students with ages ranging from 18 to 35 years who presented pathological jealousy. The therapeutic process used was based on the cognitive-behavioral intervention guide for jealousy management in couple relationships. Under an AB design, the intervention had a timespan of two months and was developed throughout seven sessions. A follow-up was performed six months later for two of the six subjects. The results show a decrease in Interpersonal Jealousy Scale score and significant differences were found in the global results of the IJS scores in pre- and post-application of the intervention (p<,05). Other differences were seen in the frequency of behavior associated to problematic jealousy. The strengths and limitations of the intervention are discussed.

Subtipos neurocognitivos de esquizofrenia / Neurocognitive Subtypes of Schizophrenia

Objetivo. Identificar empíricamente subtipos neurocognitivos de esquizofrenia y establecer la asociación de estos con características clínicas. Métodos. Se aplicaron pruebas de atención sostenida, función ejecutiva, reconocimiento facial de emociones, memoria verbal y de trabajo a 253 sujetos con esquizofrenia. A partir de los resultados de estas pruebas se identificaron los subtipos mediante análisis de clases latentes. Posteriormente, se evaluó la asociación de cada subtipo con características clínicas. Resultados. Se identificaron cuatro subtipos: 1) déficit cognitivo global, 2) déficit de memoria y función ejecutiva, 3) déficit de memoria y reconocimiento de emociones y 4) sin déficit cognitivo. Al comparar con el subtipo sin déficit cognitivo, se observó que tanto el de déficit de memoria y función ejecutiva como el de déficit cognitivo global tenían mayor frecuencia individuos de sexo masculino, desempleados, con deterioro grave y adherentes al tratamiento. Sin embargo, en el subtipo con déficit cognitivo global la diferencia fue más alta y presentaron una frecuencia más baja de antecedentes de episodios depresivos (OR 0,39; IC95%: 0,16 a 0,97). El subtipo de déficit de memoria y reconocimiento emocional tenía más sujetos con deterioro grave (OR 5,52; IC95%: 1,89 a 16,14) y desempleo (OR 2,43; IC95%: 1,06 a 5,55), pero menos con antecedentes de episodios depresivos (OR 0,21; IC95%: 0,07 a 0,66). Conclusión. Los resultados muestran cuatro subtipos neurocognitivos de esquizofrenia con un posible espectro de severidad, asociándose en un extremo con mayor disfunción, y en el otro con mayor psicopatología afectiva y menor adherencia al tratamiento

Objective. To empirically identify schizophrenia neurocognitive subtypes and establish their association with clinical characteristics. Methods. Sustained attention, executive function, facial emotion recognition, verbal learning, and working memory tests were applied to 253 subjects with schizophrenia. We identified neurocognitive subtypes by a latent class analysis of the tests results. After, we made a search for the association of these subtypes with clinic characteristics. Results. We identified four neurocognitive subtypes: 1) 'Global cognitive deficit', 2) 'Memory and executive function deficit', 3) 'Memory and facial emotion recognition deficit,' and 4) 'Without cognitive deficit.' In comparison with the subtype 'without cognitive deficit,' we found that the 'memory and executive function deficit subtype' and the 'global cognitive deficit subtype' had a higher frequency of male, unemployed, severe impairment, and adherence to treatment participants. However, in the 'global cognitive deficit subtype' the differences were higher and there was also a lower frequency of past major depressive episodes (OR 0.39; 95%CI: 0.16 to 0.97). The 'memory and facial recognition deficit subtype' had a higher probability of severe impairment (OR 5.52; 95%CI: 1.89 to 16.14) and unemployed (OR 2.43; 95%CI: 1.06 to 5.55) participants, but also a lower probability of past depressive episodes (OR 0.21; 95%CI: 0.07 to 0.66). Conclusion. Our results suggest the existence of four neurocognitive subtypes in schizophrenia with a spectrum of dysfunction and severity. We found higher dysfunction in those with worse cognitive dysfunction, and higher affective psychopathology and less treatment adherence in those with less cognitive dysfunction

Neurocognitive subtypes of schizophrenia.

OBJECTIVE: To empirically identify schizophrenia neurocognitive subtypes and establish their association with clinical characteristics. METHODS: Sustained attention, executive function, facial emotion recognition, verbal learning, and working memory tests were applied to 253 subjects with schizophrenia. We identified neurocognitive subtypes by a latent class analysis of the tests results. After, we made a search for the association of these subtypes with clinic characteristics. RESULTS: We identified four neurocognitive subtypes: 1) “Global cognitive deficit”, 2) “Memory and executive function deficit”, 3) “Memory and facial emotion recognition deficit,” and 4) “Without cognitive deficit.” In comparison with the subtype “without cognitive deficit,” we found that the “memory and executive function deficit subtype” and the “global cognitive deficit subtype” had a higher frequency of male, unemployed, severe impairment, and adherence to treatment participants. However, in the “global cognitive deficit subtype” the differences were higher and there was also a lower frequency of past major depressive episodes (OR 0.39; 95%CI: 0.16 to 0.97). The “memory and facial recognition deficit subtype” had a higher probability of severe impairment (OR 5.52; 95%CI: 1.89 to 16.14) and unemployed (OR 2.43; 95%CI: 1.06 to 5.55) participants, but also a lower probability of past depressive episodes (OR 0.21; 95%CI: 0.07 to 0.66). CONCLUSION: Our results suggest the existence of four neurocognitive subtypes in schizophrenia with a spectrum of dysfunction and severity. We found higher dysfunction in those with worse cognitive dysfunction, and higher affective psychopathology and less treatment adherence in those with less cognitive dysfunction.

Sensibilidad en el Reconocimiento de Emociones Faciales Como Endofenotipo de Esquizofrenia / Sensitivity in the Recognition of Facial Emotions as an Endophenotype for Schizophrenia / Sensibilidade no Reconhecimento de Emoções Faciais Como Endofenótipo de Esquizofrenia

Los endofenotipos son rasgos presentes antes de la aparición de un trastorno y podrían ser útiles para identificar genes de susceptibilidad. Se determinó si personas con esquizofrenia y sus familiares de primer grado no afectados tenían un desempeño menor que los controles en la Tarea de Multitransformación de Expresión Emocional, que mide reconocimiento de emociones faciales. Las personas con esquizofrenia y sus familiares mostraron menor sensibilidad o requirieron más intensidad para identificar emociones que los controles. La exactitud para identificar emociones fue similar entre familiares y controles, pero menor en aquellos con esquizofrenia. Esto sugiere que la sensibilidad para el reconocimiento de emociones faciales es un endofenotipo de la esquizofrenia.

Endophentoypes are the traits present before the appearance of a disorder and could be useful to identify susceptibility genes. The purpose of this study was to determine whether persons suffering from schizophrenia and their immediate relatives performed less well than controls in the Emotional Expression Multi-transformation Task, which measures recognition of facial expressions. Persons with schizophrenia and their relatives showed less sensitivity than controls or required greater intensity to identify emotions than controls did. Accuracy in the identification of emotions was similar in relatives and controls, but lower in individuals with schizophrenia. This suggests that sensitivity in the recognition of facial emotions is an endophenotype for schizophrenia.

Os endofenótipos são traços presentes antes do surgimento de um transtorno e poderiam ser úteis para identificar genes de suscetibilidade. Determinou-se se pessoas com esquizofrenia e seus familiares de primeiro grau não afetados tinham um desempenho menor que os controles na Tarefa de Multitransformação de Expressão Emocional, que mede reconhecimento de emoções faciais. As pessoas com esquizofrenia e seus familiares mostraram menor sensibilidade ou requereram mais intensidade para identificar emoções que os controles. A exatidão para identificar emoções foi similar entre familiares e controles, mas menor naqueles com esquizofrenia. Isso sugere que a sensibilidade para o reconhecimento de emoções faciais é um endofenótipo da esquizofrenia.

Verbal working memory in individuals with schizophrenia and their first degree relatives: relationship with negative and disorganized symptoms.

OBJECTIVE: To determine whether there are differences in verbal working memory amongst subjects with schizophrenia, their first degree relatives and controls, and to evaluate the influence of symptoms on these differences, as an initial step to assess whether this cognitive function is an endophenotype. METHODS: We examined 197 cases with schizophrenia, 197 first degree relatives and 200 controls through psychiatric interviews and the Letters and Numbers Sequencing test (LNS). Performance was compared among the three groups adjusting for age, sex and education level. Adjustment for "negative symptoms" and "disorganization" was performed afterwards. RESULTS: Subjects with schizophrenia showed lower performance in the LNS than their first degree relatives and the healthy controls; the effect sizes were 0.75 and 1.18 respectively. There was a small difference between relatives and controls (effect size =0.38). These differences were significant after adjustment for negative and disorganized symptoms, but the effect sizes became smaller: 0.26 for relatives vs. subjects with schizophrenia, 0.56 for controls vs. subjects with schizophrenia and 0.33 for relatives vs. controls. Among individuals with schizophrenia, performance in the LNS was not associated with disorder duration, disease onset age, antipsychotics, history of depressive episodes or substance use disorders. CONCLUSION: Results suggest verbal working memory may be considered as an endophenotype in schizophrenia.

Memoria de trabajo verbal en individuos con esquizofrenia y sus familiares de primer grado: Relación con los sintomas negativos y desorganizados / Verbal working memory in individuals with schizophrenia and their first degree relatives: relationship with negative and disorganized symptoms

Objetivo: Determinar si hay diferencias en la memoria de trabajo verbal entre sujetos con esquizofrenia, familiares de primer grado y controles, y evaluar la influencia que pueden tener en estas diferencias los síntomas del trastorno, como un paso para establecer si esta función cognitiva es un endofenotipo. Métodos: A 197 sujetos con esquizofrenia, 197 familiares de primer grado y 200 controles comunitarios, se les hizo evaluación psiquiátrica y se les aplicó la prueba sucesión de letras y números (SLN). Se comparó el desempeño de los tres grupos ajustando por edad, sexo y escolaridad, y luego se ajustó también por síntomas negativos y desorganizados. Resultados: Los sujetos con esquizofrenia mostraron un menor desempeño en la SLN con respecto a sus familiares de primer grado no-afectados y los controles, con tamaños de efecto de 0,75 y 1,18 respectivamente. Hubo una diferencia pequeña pero significativa entre familiares y controles (tamaño de efecto =0,38). Estas diferencias siguieron siendo significativas después de ajustar por síntomas negativos y desorganizados, pero los tamaños de efecto disminuyeron a: 0,26 para familiares vs sujetos con esquizofrenia, 0,56para controles vs sujetos con esquizofrenia y 0,33 para familiares vs controles. Entre los sujetos con esquizofrenia, el desempeño en la SLN no se asoció significativamente con duración del trastorno, edad de inicio, uso de antipsicóticos, ni historia de episodios depresivos o trastornos por uso de sustancias. Conclusión: Los resultados sugieren que la memoria de trabajo verbal puede ser considerada un endofenotipo de la esquizofrenia (AU)

Objective: To determine whether there are differences in verbal working memory amongst subjects with schizophrenia, their first degree relatives and controls, and to evaluate the influence of symptoms on these differences, as an initial step to assess whether this cognitive function is an endophenotype. Methods: We examined 197 cases with schizophrenia, 197 first degree relatives and 200 controls through psychiatric interviews and the Letters and Numbers Sequencing test (LNS). Performance was compared among the three groups adjusting for age, sex and education level. Adjustment for “negative symptoms” and “disorganization” was performed afterwards. Results: Subjects with schizophrenia showed lower performance in the LNS than their first degree relatives and the healthy controls; the effect sizes were 0.75 and 1.18 respectively. There was a small difference between relatives and controls (effect size =0.38). These differences were significant after adjustment for negative and disorganized symptoms, but the effect sizes became smaller: 0.26 for relatives vs. subjects with schizophrenia, 0.56 for controls vs. subjects with schizophrenia and 0.33 for relatives vs. controls. Among individuals with schizophrenia, performance in the LNS was not associated with disorder duration, disease onset age, antipsychotics, history of depressive episodes or substance use disorders. Conclusion: Results suggest verbal working memory may be considered as an endophenotype in schizophrenia (AU)

Reduced modeling and state observation of an activated sludge process.

This article first proposes a reduction strategy of the activated sludge process model with alternated aeration. Initiated with the standard activated sludge model (ASM1), the reduction is based on some biochemical considerations followed by linear approximations of nonlinear terms. Two submodels are then obtained, one for the aerobic phase and one for the anoxic phase, using four state variables related to the organic substrate concentration, the ammonium and nitrate-nitrite nitrogen, and the oxygen concentration. Then, a two-step robust estimation strategy is used to estimate both the unmeasured state variables and the unknown inflow ammonium nitrogen concentration. Parameter uncertainty is considered in the dynamics and input matrices of the system.

Caracterización molecular de los genes histona H2A y ARNsno-Cl de Trypanosoma rangeli: aplicación en pruebas diagnósticas / Molecular characterization of histone H2A and snoRNA-Cl genes of Trypanosoma rangeli: application in diagnostic tests

La aplicación de la reacción en cadena de la polimerasa (PCR) para detectar e identificar Trypanosoma rangeli y Trypanosoma rangeli presenta a menudo dificultades de interpretación. Así, algunas pruebas generan la amplificación de bandas similares provenientes de uno de los dos parásitos, fragmentos polimórficos de un mismo parásito, o la prevalencia en la detección de T. cruzi en infecciones mixtas. En este estudio se presentan y analizan los trabajos de investigación básica realizados con el objeto de diseñar y estandarizar pruebas de PCR específicas de cada parásito. Los iniciadores TcH2AF/R se diseñaron sobre la base de la región diferencial observada entre las unidades génicas que contienen los genes h2a en estos tripanosomas. Esta pareja de iniciadores amplifican un fragmento de 234 pb específico para T. cruzi (cepas I y II). Los iniciadores TrF/R2 anillan en las regiones intergénicas del fragmento génico de 801 pb codificante para seis transcritos que forman la agrupación ARNsno-Cl en T. rangeli. Estos iniciadores amplifican un fragmento de 620 pb exclusivo de las cepas KP1(-) y KP1(+) de este parásito. La aplicación de estas PCR en vectores infectados y en pacientes con enfermedad de Chagas muestra que ambas pruebas constituyen herramientas útiles para el diagnóstico y la identificación diferencial de estos tripanosomátidos.

The application of polymerase chain reaction (PCR) to detect Trypanosoma rangeli and Trypanosoma rangeli often presents interpretation challenges. For example, some tests yield the amplification of similar bands from either parasite, polymorphic fragments of the same parasite, or present deviation towards T. cruzi in mixed infections. In this study, the basic researching needed for designing and standardizating specific PCR tests for each parasite species PCR are shown and analyzed. The TcH2AF/R primers were designed on the basis of the differential gene region observed between the histone h2a genic units of these parasites. These primers amplify a specific 234 bp fragment in T. cruzi (T. cruzi I and II strains). The TrF/R2 primers anneal to the intergenic regions of an 801 bp gene fragment encoding for six transcripts that conform the snoRNA-Cl cluster in T. rangeli. These primers amplify a fragment of 620 bp exclusively in KP1(-) and KP1(+) strains of the parasite. The application of these PCR tests in infected vectors and in chagasic patients show that both tests constitute useful tools for the diagnosis and differential identification of these Trypanosomatids. Key words: histone, RNA small nucleolar (snoRNA), polymerase chain reaction (PCR), Trypanosoma.

[Comparison of a PCR test based on the histone H2A/SIRE genes with classical serological tests for the diagnosis of chronic Chagas disease in Colombian patients]. / Comparación de una prueba de PCR basada en los genes codificantes para la histona H2A/SIRE con pruebas serológicas convencionales para el diagnóstico de la enfermedad de Chagas crónica en pacientes colombianos.

INTRODUCTION: Diagnosis of Chagas disease in its latent and chronic phase is difficult because of the low parasitemia levels. Therefore, serological and molecular techniques are necessary to achieve an appropriate diagnosis. OBJECTIVE: The polymerase chain reaction based on the amplification of the SIRE element inserted into H2A encoding genes was compared with classical serological tests for the diagnosis of Chagas disease in Colombian patients. MATERIALS AND METHODS: An agreement study was carried out by comparing the PCR with ELISA (enzyme linked immuno sorbent assay) and IFAT (indirect immunofluorescence) tests. In addition, the PCR sensitivity and specificity were determined. A sample of 156 individuals was tested with the H2A PCR primers after a Chagas disease classification based on clinical, epidemiological and serological data associated with each patient. In addition, 97 out of 156 samples were also compared with the S35/S36 PCR primers. RESULTS: Eighty-nine of 156 samples (57%) were positive by both IFAT and ELISA and 84 (53.8%) presented the expected 234 bp amplification fragment. The sensitivity of the TcH2AF/ R PCR was 88% (95% C.I.: 75%--95%) and its specificity 92.5% (95% C.I.: 87.7%--97.2%). The kappa index for concordance between serological tests and TcH2AF/R PCR was 0.8 (95% C.I.: 73%--86%), and between the TcH2AF/R and S35/S36 PCR primers was 0.9 (95% C.I.: 84%-96%). These indices indicated a "good" and "almost perfect" agreement, respectively. CONCLUSIONS: The TcH2AF/R PCR is a promising diagnostic tool for the detection of T. cruzi and is suggested as a tool complementary to the classical serological tests.

Comparación de una prueba de PCR basada en los genes codificantes para la histona H2A/SIRE con pruebas serológicas convencionales para el diagnóstico de la enfermedad de Chagas crónica en pacientes colombianos / Comparison of a PCR test based on the histone H2A/SIRE genes with classical serological tests for the diagnosis of chronic Chagas disease in Colombian patients

Introducción. El diagnóstico de la enfermedad de Chagas en sus fases latente y crónica se dificulta por la baja parasitemia, razón por la cual se recurre a métodos serológicos y moleculares. Objetivo. Comparar la prueba de reacción en cadena de la polimerasa basada en la amplificación del elemento SIRE insertado en el gen que codifica para la histona H2A con las pruebas serológicas convencionales para el diagnóstico de la enfermedad de Chagas en pacientes colombianos. Materiales y métodos. Se realizó un estudio de concordancia comparando la PCR TcH2AF/R con las pruebas de inmunoensayo enzimático e inmunofluorescencia indirecta, determinándose además la sensibilidad y especificidad de la prueba. Se clasificaron y examinaron 156 individuos según los hallazgos clínicos y epidemiológicos y los resultados de las pruebas serológicas. Adicionalmente, 97 de las 156 muestras fueron comparadas con la PCR S35/S36. Resultados. De 156 muestras, 89 (57 por ciento) fueron positivas por IFI y ELISA, y 84 (53,8 por ciento) presentaron el perfil de amplificación correspondiente a la banda esperada de 234 pb, obteniéndose una sensibilidad de 88 por ciento (I.C. 95 por ciento: 75 por ciento - 95 por ciento) y especificidad de 92,5 por ciento (I.C. 95 por ciento: 87,7 por ciento - 97,2 por ciento). El índice kappa, indicador de concordancia entre las pruebas serológicas y TcH2AF/R fue de 0,8 (I.C. 95 por ciento: 73 por ciento - 86 por ciento), en tanto entre las PCR TcH2AF/R y S35/S36 fue de 0,9 (I.C. 95 por ciento: 84 por ciento - 96 por ciento), interpretados como una concordancia buena y casi perfecta, respectivamente. Conclusiones. La PCR TcH2AF/R es una prueba diagnóstica promisoria complementaria a las pruebas serológicas, para la detección de Trypanosoma cruzi.

Introduction. Diagnosis of Chagas disease in its latent and chronic phase is difficult because of the low parasitemia levels. Therefore, serological and molecular techniques are necessary to achieve an appropriate diagnosis. Objective. The polymerase chain reaction based on the amplification of the SIRE element inserted into H2A encoding genes was compared with classical serological tests for the diagnosis of Chagas disease in Colombian patients. Materials and methods. An agreement study was carried out by comparing the PCR with ELISA (enzyme linked immuno sorbent assay) and IFAT (indirect immunofluorescence) tests. In addition, the PCR sensitivity and specificity were determined. A sample of 156 individuals was tested with the H2A PCR primers after a Chagas disease classification based on clinical, epidemiological and serological data associated with each patient. In addition, 97 out of 156 samples were also compared with the S35/S36 PCR primers. Results. Eighty-nine of 156 samples (57%) were positive by both IFAT and ELISA and 84 (53.8%) presented the expected 234 bp amplification fragment. The sensitivity of the TcH2AF/ R PCR was 88% (95% C.I.: 75%--95%) and its specificity 92.5% (95% C.I.: 87.7%--97.2%). The kappa index for concordance between serological tests and TcH2AF/R PCR was 0.8 (95% C.I.: 73%--86%), and between the TcH2AF/R and S35/S36 PCR primers was 0.9 (95% C.I.: 84%-- 96%). These indices indicated a “good” and “almost perfect” agreement, respectively. Conclusions. The TcH2AF/R PCR is a promising diagnostic tool for the detection of T. cruzi and is suggested as a tool complementary to the classical serological tests.

The systemic inflammatory response syndrome (SIRS) to identify infected patients in the emergency room.

OBJECTIVE: Evaluation of the usefulness of criteria for systemic inflammatory response syndrome (SIRS) compared with the final diagnosis of infection in patients admitted to the emergency room of two university-based hospitals. DESIGN: Longitudinal cohort study. SETTING: Hospital Universitario San Vicente de Paul and Hospital General de Medellín, Medellín, Colombia. PATIENTS. Seven hundred thirty-four patients with suspected infection as main diagnosis for admittance into the emergency room. MEASUREMENTS AND RESULTS: Sensitivity, specificity, predictive values and likelihood ratios (LR) of SIRS criteria at admission were determined using, as gold standards, the diagnosis at the time of discharge based on clinical history and evolution, and microbiological confirmation of infection. SIRS criteria were met by 503 patients (68.5%); the discharge diagnosis of infection was found in 657 (89.4%) and 276 (37%) had microbiological confirmation. SIRS criteria exhibited a sensitivity of 69%, specificity of 35%, positive predictive value (PPV) of 90%, negative predictive value (NPV) of 12% and positive LR of 1.06. There were no differences between the two gold standards. CONCLUSIONS: The finding of two or more SIRS criteria was of little usefulness for diagnosis of infection. It is necessary to work with new criteria and probably with biological markers, in order to obtain a simple, precise and operative definition of the sepsis phenomenon.

Utilidad y aplicación de los criterios para el Síndrome de Respuesta Inflamatoria Sistémica (SIRS) en pacientes con infección severa admitidos en urgencias / Sistemic inflammatory response syndrome criteria usefulness and aplication in emergency patients with severe infección

Objetivo: evaluación de la utilidad de los criterios para SIRS comparados con el diagnóstico final de infección en pacientes admitidos en urgencias de dos hospitales universitarios. Diseño: estudio de cohorte longitudinal. Sitio: Hospital Universitario San Vicente de Paúl y Hospital General de Medellín, Medellín, Colombia. Pacientes: 734 pacientes con sospecha de infección como diagnóstico principal para la admisión en urgencias. Mediciones: la sensibilidad, la especificidad, los valores predictivos y las razones de probabilidad (RP) de los criterios de SIRS en la admisión, fueron determinados usando como estándares de oro el diagnóstico en el momento del alta basado en la historia clínica y la evolución, y la confirmación microbiológica de la infección. Resultados: se encontraron criterios para SIRS en 503 pacientes (68.5 por ciento), el diagnóstico de infección fue encontrado en 657 (89.4 por ciento) y 276 (37 por ciento) tenían confirmación microbiológica. Los criterios para SIRS mostraron una sensibilidad de 69 por ciento, una especificidad de 35 por ciento, un valor predictivo positivo (VPP) de 90 por ciento, un valor predictivo negativo (VPN) de 12 por ciento y un RP positivo de 1.06. No hubo diferencias entre ambos estándares de oro. Conclusiones: el hallazgo de dos o más criterios para SIRS fue de poca utilidad para el diagnóstico de infección. Es necesario evaluar nuevos criterios para obtener una definición simple, precisa y operativa del fenómeno de la sepsis

Factores pronosticos en el sindrome de respuesta inflamatoria sistemica (SRIS): Desarrollo de un indice de severidad / Prognosis factors in SIRS

Objetivo: desarrollar un índice de severidad para el síndrome de respuesta inflamatoria sistémica (SRIS) de etiología infecciosa comprobada o probable, que determine la probabilidad de muerte desde el momento de la admisión en urgencias. Diseño: estudio observacional analítico en una cohorte concurrente. Lugar de estudio: servicios de urgencias del Hospital Universitario San Vicente de Paúl y el Hospital General de Medellín Luz Castro de Gutiérrez. Pacientes: admitidos por urgencias con SRIS de etiología no traumática entre agosto de 1998 y marzo de 1999, de edad igual o superior a 14 años y con cambios en la temperatura o en el recuento de blancos como uno de los criterios necesarios para la definición del síndrome. Intervenciones: reclutamiento de la población de estudio y recolección de la información pertinente, de manera directa, en los servicios de urgencias de las dos instituciones. Mediciones: variables predictivas: edad, enfermedad sistémica inmunosupresora (ESI: cáncer, SIDA, uso de esferoides o quimioterapia), enfermedad sistémica general (ESG: insuficiencia cardíaca, insuficiencia renal, diabetes, enfermedad pulmonar obstructiva crónica o cirrosis), índice de choque, temperatura, frecuencia respiratoria, escala de Glasgow, recuento de leucocitos, recuento de plaquetas y valor de creatinina. Variable de desenlace: mortalidad intrahospitalaria dentro de los primeros 30 días de la admisión por urgencias. Análisis bivariado exploratorio y análisis de regresión logística paso a paso, asignación de puntaje de acuerdo con los coeficientes de regresión de las variables admitidas, evaluación de la capacidad discriminativa por medio del índice C y de la capacidad predictiva por medio del estadístico de Hosmer-Lemeshow. Resultados: fueron admitidos 533 pacientes, 45 por ciento mujeres, con un promedio de edad de 48 años y una estancia hospitalaria media de 11 días. El 14 por ciento requirió manejo en cuidado intensivo. Los principales diagnósticos de admisión fueron neumonía (36.3 por ciento), infección de piel y tejidos blandos (17 por ciento) y bacteremia o sepsis (13 por ciento...