We reviewed from a bioethical perspective and attempting prevention of potential conflicts derived communication failure during medical practice, palliative treatments and dignified death in the institutional practice as well as general practice; most of conflicts related to patient-doctor relationship could de prevented. We propose an attitude and aptitude plus in deep knowledge of patient, family, friends and legal representatives in terms fully honest communication to prevent most of conflicts and avoid its consequences against doctors and other health workers. Prevention is better and it depends of knowledge of norms, laws, general beliefs and common sense in this country and maybe others.

Con la intención de prevenir conflictos en el acto médico y desde el punto de vista bioético, éste, el manejo paliativo y de la muerte digna; situaciones que pueden ser fuente de demandas entre el paciente y el médico. Sostenemos que la actitud y aptitud del médico, del paciente, su familia, amigos y representantes legales, con apertura y honestidad, pueden prevenir la gran mayoría de las causas de conflicto y evitar las consecuencias del mismo entre los profesionales de la salud y los enfermos. La prevención es posible si hay buena voluntad y conocimiento de normas, leyes, usos y sentido común.

In nearly all of the previous multicentre studies evaluating serological tests for Trypanosoma cruzi infection, sera samples from Central or South American countries have been used preferentially. In this work we compared the reliability of the serological tests using Mexican sera samples that were evaluated in four independent laboratories. This included a reference laboratory in Brazil and three participant laboratories, including one in Central America and two in Mexico. The kappa index between Brazilian and Honduran laboratories reached 1.0 and the index for the Mexican laboratories reached 0.94. Another finding of this study was that the source of antigen did not affect the performance of the serological tests.

Northern Veracruz has conditions, biotic and abiotic, to support Triatomine bugs and vectorial transmission of Trypanosoma cruzi to human beings. Therefore we explore seroprevalence of antibodies to this parasite and the presence of Chronic Chagasic Cardiopathy (CCC) at Cardiology ward in a General Hospital serving North of Veracruz State, and neighbord states Hidalgo, Puebla San Luis Potosí and Tamaulipas. Material and methods: We search for consecutive adult patients attending outpatient and beds assigned to Cardiology between March through September, 2003. An epidemiology questionnaire, clinical work up, chest roentgenogram, 12 lead peripheral EKG and transthoracic echocardiogram were performed in 240 female/males patients. All of them were bled to blindly search for T. cruzi antibodies. Results: Seroprevalence was 8%, 49 cases of dilated cardiomyopathy were diagnosed 23 attributed to chronic diseases such as systemic hypertension diabetes mellitus or ischemic heart disease 12 with idiopathic disease and 14 (29%) had CCC. The latter accumulated epidemiologic features suggestive of vectorial infection. Four additional individuals without CCC but having specific antibodies were considered indeterminate Chagasic cases. Discussion and conclusions: This case series identify American Trypanosomiasis among 19 people attending a Cardiology Service, and 14 of them had a severe heart disease linked to progressive and fatal course. This observation points out that Chagas disease could be a regional public health problem in Northern Veracruz.

La zona del norte de Veracruz reúne condiciones para la transmisión vectorial de Trypanosoma cruzi. Se buscaron anticuerpos anti T. cruzi y cardiopatía chagásica crónica (CCC) en el Servicio de Cardiología en el Hospital General N° 24. Material y métodos: Técnicas validadas ELISA/IFI en adultos de ambos sexos entre marzo y septiembre de 2003. Se hizo cuestionario epidemiológico, historia clínica, índice cardio-torácico (ICT), ECG y ecocardiograma transtorácico. Se calculó prevalencia y describimos datos clínicos. Resultados: La seroprevalencia fue del 8%, 19/240 pacientes, 49 tenían diagnóstico de miocardiopatía dilatada (MD), 23 secundaria, 12 MD y 14 CCC. Los seropositivos tuvieron edad media de 58 años, 11 mujeres, el origen rural, vivienda precaria, hacinamiento, conocimiento del vector y convivencia con animales eran comunes. Cinco donaron y 4 recibieron sangre, 6 bebedores sociales y 2 fumadores. La CCC ocurrió en 14 seropositivos, 1 más, tuvo trastorno del ritmo, hubo 4 chagásicos indeterminados. Promedios grupales: fracción de eyección 41%, DDVI de 57 mm, 13 con hipocinesia generalizada e ICT > 0.54. Tres requirieron marcapaso definitivo. Conclusiones: La prevalencia de seropositivos, casi 5 veces mayor que la media nacional, principalmente en individuos con MD y trastornos del ritmo (15/ 19-79%) apoya el diagnóstico de CCC.

OBJECTIVE: To compare the epidemiological and clinical characteristics of chronic Chagas' heart disease to other dilated cardiomyopathies. METHODS: A study comprising 128 patients from a heart disease center was carried out from 1993 to 2003. Of them, 51 (40%) were Trypasonoma cruzi positive. Epidemiological data was obtained through interviews and clinical and serological data from health services. Statistic analysis was conducted using the Chi-square, Fischer, Mann-Whitney or Students' t-test as well as multivariate analysis. RESULTS: Chronic Chagas' disease patients were older (55±10 years old) than those patients with cardiopathy (42±17 years old). Most of them were born in rural areas (90% vs 68%), lived in poor (75% vs 16%), crowded households (45% vs 20%), together with domestic animals (71% vs 61%) and were aware of the Chagas' vector (73% vs 25%). Rhythm and conduction ECG abnormalities as well as permanent pacemaker were common among Chagas' patients (84% vs 55%, 78% vs 64% and 24% vs 10%, respectively). Congestive heart failure was more frequent among cardiomiopathy patients (88% vs 71%). Both groups had abnormal myocardial perfusion with normal epicardial arteries. Comorbidities were more frequent in cardiomiopathy patients than in chronic Chagas' disease patient (two cases only). CONCLUSIONS: Chagas' disease is the most common cause of dilated cardiomiopathy in the study hospital. Due to its regional distribution in Mexico, it deserves special attention and control programs proven to be effective in other countries.

OBJECTIVO: Comparar las características epidemiológicas y clínicas de la cardiopatía chagásica crónica con otras miocardiopatías dilatadas. MÉTODOS: Se incluyeron a 128 pacientes consecutivos en un hospital de espcialidad, de 1993 a 2003 con miocardiopatías dilatadas, donde 51 (40%) con anti Tripanosoma cruzi. Se recopiló información epidemiológica por entrevista directa, y datos clínicos en los servicios asistenciales. Se utilizaron la prueba de la Chi-cuadrado o prueba exacta de Fischer, prueba t de Student ó la prueba de U de Mann Whitney y análisis multivariado. RESULTADOS: Los pacientes con cardiopatía chagásica crónica, eran más viejos (55±10 años) que los pacientes con miocardiopatías (42±17 años), nacieron en zonas rurales (90% vs 68%), en viviendas precarias (75% vs 16%), con hacinamiento (45% vs 20%), convivencia con animales domésticos (71% vs 61%) y conocían al vector (73% vs 25%). Los trastornos del ritmo y de la conducción, así como la colocación de marcapaso definitivo fueron frecuentes en los pacientes con cardiopatía chagásica crónica (84% vs 55%, 78% vs 64% Y 24% vs 10% respectivamente). La insuficiencia cardiaca congestiva venosa fue más frecuente en los pacientes con miocardiopatía seronegativa (88% vs 71%) y la perfusión miocárdic anormal con arterias epicárdicas normales fue igual en ambos grupos. Con respecto a co-morbilidad, los pacientes con cardiopatía chagásica crónica tenían sólo dos padecimientos, mientras que en el otro grupo era más amplia. CONCLUSIÓNES: La enfermedad de Chagas causa la miocardiopatía dilatada específica más común. Debido a su distribución regional en la República Mexicana, merece atención y se recomienda a nivel público adoptar medidas de prevención que ya probaron eficacia en otros países.

OBJECTIVE: To compare the epidemiological and clinical characteristics of chronic Chagas' heart disease to other dilated cardiomyopathies. METHODS: A study comprising 128 patients from a heart disease center was carried out from 1993 to 2003. Of them, 51 (40%) were Trypasonoma cruzi positive. Epidemiological data was obtained through interviews and clinical and serological data from health services. Statistic analysis was conducted using the Chi-square, Fischer, Mann-Whitney or Students' t-test as well as multivariate analysis. RESULTS: Chronic Chagas' disease patients were older (55±10 years old) than those patients with cardiopathy (42±17 years old). Most of them were born in rural areas (90% vs 68%), lived in poor (75% vs 16%), crowded households (45% vs 20%), together with domestic animals (71% vs 61%) and were aware of the Chagas' vector (73% vs 25%). Rhythm and conduction ECG abnormalities as well as permanent pacemaker were common among Chagas' patients (84% vs 55%, 78% vs 64% and 24% vs 10%, respectively). Congestive heart failure was more frequent among cardiomiopathy patients (88% vs 71%). Both groups had abnormal myocardial perfusion with normal epicardial arteries. Comorbidities were more frequent in cardiomiopathy patients than in chronic Chagas' disease patient (two cases only). CONCLUSIONS: Chagas' disease is the most common cause of dilated cardiomiopathy in the study hospital. Due to its regional distribution in Mexico, it deserves special attention and control programs proven to be effective in other countries.

OBJECTIVO: Comparar las características epidemiológicas y clínicas de la cardiopatía chagásica crónica con otras miocardiopatías dilatadas. MÉTODOS: Se incluyeron a 128 pacientes consecutivos en un hospital de espcialidad, de 1993 a 2003 con miocardiopatías dilatadas, donde 51 (40%) con anti Tripanosoma cruzi. Se recopiló información epidemiológica por entrevista directa, y datos clínicos en los servicios asistenciales. Se utilizaron la prueba de la Chi-cuadrado o prueba exacta de Fischer, prueba t de Student ó la prueba de U de Mann Whitney y análisis multivariado. RESULTADOS: Los pacientes con cardiopatía chagásica crónica, eran más viejos (55±10 años) que los pacientes con miocardiopatías (42±17 años), nacieron en zonas rurales (90% vs 68%), en viviendas precarias (75% vs 16%), con hacinamiento (45% vs 20%), convivencia con animales domésticos (71% vs 61%) y conocían al vector (73% vs 25%). Los trastornos del ritmo y de la conducción, así como la colocación de marcapaso definitivo fueron frecuentes en los pacientes con cardiopatía chagásica crónica (84% vs 55%, 78% vs 64% Y 24% vs 10% respectivamente). La insuficiencia cardiaca congestiva venosa fue más frecuente en los pacientes con miocardiopatía seronegativa (88% vs 71%) y la perfusión miocárdic anormal con arterias epicárdicas normales fue igual en ambos grupos. Con respecto a co-morbilidad, los pacientes con cardiopatía chagásica crónica tenían sólo dos padecimientos, mientras que en el otro grupo era más amplia. CONCLUSIÓNES: La enfermedad de Chagas causa la miocardiopatía dilatada específica más común. Debido a su distribución regional en la República Mexicana, merece atención y se recomienda a nivel público adoptar medidas de prevención que ya probaron eficacia en otros países.

Acute myocarditis (AM) is associated with viral infections: Coxsackie and ECHOviruses among others. Autoimmunity has been proposed as a pathogenic mechanism. Benefit of classic immunosuppression (prednisone-azathioprine) or immunomodulation (monomeric-human IgG) is still uncertain. Objective: To review incidence and clinical approach to AM at a Cardiology referral center. Material and methods: A 10-yeard period (1992-2003) is reviewed. A standard ques-tionary was applied to 49 consecutive patients referred by clinicians with a diagnosis of AM. Results: AM was found in 17 women and 32 men, median age 24 and 28 years, respectively. They presented heart failure with dyspnea/ortop-nea (70-47%), peripheral edema/jugular vein plethora (41-37%), chest pain, and tachycardia (50%), NYHA functional class was III-IV in 22. The EKG showed sinus tachycardia or conduction defects. Transthoracic echocardiograms in 47 cases showed EF (mean) of 41% with enlarged left ventricle diameter. Antivirus antibodies were present in 54% of those cases studied, Coxsackie or ECHOvirus were identified through a serologic assay. Twenty-nine (61%) of our cases developed dilated cardiomyopathy, three patients died. It is not possible to reach a conclusion regard to immunomodulation therapy, because it was applied to only 12 patients. Conclusions: At the Instituto Nacional de Cardiología "I. Chávez", AM depicts an incidence of 1/1,000 patients a year. It is necessary to standardize the clinical approach for diagnosis and treatment, progression to dilated cardiomyopathy and deadth during acute stage occurs in two-thirds of our patients

La miocarditis aguda (MA) se asocia a infecciones virales: Coxsackie B, ECHOvirus y otros. Mecanismos autoinmunes se suponen patogénicos. La clínica es variable. El beneficio de inmunosupresión clásica (prednisona-azatioprina) o inmunomodulación (IgG-monomérica) no ha sido confirmado. Objetivo: Revisar la incidencia y enfoque de estudio de la miocarditis. Material y métodos: De 1992-2003, aplicamos un cuestionario estándar a 49 pacientes consecutivos con diagnóstico establecido en forma independiente. Se excluyeron MA con causa identificable. Resultados: La MA ocurrió en 17 mujeres y 32 hombres, edad (mediana) 24 y 28 años. Predominaron disnea/ortopnea (70-47%), edema/plétora yugular (41-37%), dolor precordial y taquicardia (50%). En 22 (45%) la clase funcional era III-IV. El electrocardiograma mostró taquicardia sinusal (35%) y bloqueos de rama (24%). En 47 pacientes el ecocardiograma mostró FEVI 41% (promedio), DDVI 53 mm (promedio) y discinesia 89%. En 11 (22%) casos investigamos anticuerpos contra Coxsackie/ECHOvirus, 6 (54%) tenían anticuerpo reconocido. Veintinueve casos (61%) progresaron a miocardiopatía dilatada (MD), hubo tres defunciones (6%). No fue posible valorar tratamiento inmunomodulador, se estudió sólo a 12 casos. Conclusiones: La incidencia de MAes 1/1,000 ingresos/año. Es necesario estandarizar manejo diagnóstico y tratamiento, pues la progresión a MD y/o muerte en etapa aguda ocurre en 2/3 de los pacientes.

Chagas disease is caused by the flagellate protozoan T. cruzi. Seroepidemiological surveys in Chiapas, Mexico have shown seropositive individuals, therefore, we searched for people affected by the chronic form of Chagas disease which involves the heart, causing a chronic, progressive and fatal disease called Chronic Chagasic Cardiopathy (CCC). Material and methods: To establish the frequency of CCC we studied 28 patients seen at the Hospital General Regional "Dr. Rafael Pascacio Gamboa" during October 2002 through October 2003 in Tuxtla Gutierrez, Chiapas, the State capital city, with diagnosis of dilated cardiomyopathy (DC), a serological survey for antibodies against T. cruzi was done. This hospital cares for people from all parts of Chiapas, Mexico. Clinical diagnosis of DC was established there and blind serological studies were performed in Mexico City. Results: Fifteen out of 28 DC patients (54%) had anti T. cruzi antibodies. All of them came from poor rural villages and they had heart failure and/or arrhythmia or heart blockade on EKG. Conclusions: This observation suggest that in Chiapas were Chagas disease is endemic, there are CCC patients. Any case with a clinical diagnosis of DC should be tested for antibodies against T. cruzi. The low socioeconomic status, culture and environment in this Mexican State favour the presence and transmission of this parasitic disease

La enfermedad de Chagas es causada por el protozoario flagelado Trypanosoma cruzi. Encuestas seroepidemiológicas realizadas en Chiapas informan individuos seropositivos en comunidades rurales, y cabe la posibilidad de que la forma crónica de la enfermedad ocurra en el estado. La expresión clínica dominante en la enfermedad de Chagas crónica es cardíaca. Material y métodos: Con el objeto de conocer la frecuencia de cardiopatía chagásica crónica (CCC) se hizo una encuesta serológica a pacientes con miocardiopatía dilatada (MD) internados entre octubre de 2002 a octubre de 2003, en el Servicio de Cardiología del Hospital General Regional "Dr. Rafael Pascacio Gamboa" de Tuxtla Gutiérrez, Chiapas. El diagnóstico fue establecido en forma independiente y el estudio seroinmunológico fue ciego. Resultados: Quince (54%) de 28 sujetos con MD tenían anticuerpos a T. cruzi. Todos provenían de medio rural pobre, su cuadro clínico incluyó insuficiencia cardíaca y/o trastornos del ritmo o conducción. Conclusiones: Esta evidencia sugiere que en Chiapas, una zona endémica de enfermedad de Chagas, hay CCC. Dentro del estudio de la MD, la etiología chagásica, debe ser considerada, ya que las condiciones socioeconómicas, culturales y regionales favorecen su presencia

Trypanosoma cruzi is classified into two major groups named T. cruzi I and T. cruzi II. In the present work we analyzed 16 stocks isolated from human cases and four isolated from triatomines from diverse geographical origins (Mexico and Guatemala). From human cases four were acute cases, six indeterminates, and six from chronic chagasic cardiophatic patients with diagnosis of dilated cardiomyopathy established based on the left-ventricular end systolic dimension and cardiothoracic ratio on chest X-radiography and impaired contracting ventricle and different degree conduction/rhythm aberrations. DNA samples were analyzed based on mini-exon (ME) polymorphism, using a pool of three oligonucleotide for the amplification of specific intergenic region of T. cruzi ME gene. All the Mexican and Guatemalan isolates regardless their host or vector origin generated a 350 bp amplification product. In conclusion T. cruzi I is dominant in Mexico and Guatemala even in acute and chronic chagasic cardiopathy patients. To our knowledge, this is the first study describing predominance of T. cruzi I in human infection for North and Central America.

OBJECTIVE: To establish the relationship between seroprevalence for antibodies against Trypanosoma cruzi and its relationship with biotic and abiotic factors. MATERIAL AND METHODS: A cross-sectional study was conducted between August 2000 and September 2001. The study population consisted of a simple random sample of 390 volunteers residing in Palmar de Bravo, Puebla, Mexico. Sample and data collection procedures included assaying antibodies against T cruzi with validated assays, and searching for domestic reservoirs and triatomine bugs. The relationship between biotic and abiotic factors with seropositivity was assessed. Statistical analysis was conducted using Kappa values for diagnostic tests; statistical significance was assessed with 2 x 2 tables, chi-squared test with Yates' correction, Fisher exact test, and odds ratios. RESULTS: The seroprevalence of T cruzi infection in humans was 4%; in domestic reservoirs (horses, pigs, and dogs) only 10% of canine reservoirs were positive. Vector species recognized were T barberi and T pallidipennis, with a Dispersion Area Index and a Colonization Index of 55% and 40%, respectively. The most important risk factors associated with positive serology were altitude (>2 150 y <2 180 meters above sea level), presence of triatomines, age, time of residence, and participation in a social assistance program. CONCLUSIONS: T cruzi infection was identified in human beings, vectors, and possibly in domestic reservoirs, in communities located over 2 000 meters above sea level.

OBJETIVO: Determinar la prevalencia de anticuerpos contra Trypanosoma cruzi y su relación con los factores bióticos y abióticos en Palmar de Bravo, Puebla, México. MATERIAL Y MÉTODOS: Estudio transversal efectuado en agosto de 2000 a septiembre de 2001, con una muestra aleatoria simple de 390 voluntarios residentes en Palmar de Bravo, Puebla, México. Se hizo determinación de anticuerpos contra T cruzi con técnicas serológicas validadas, búsqueda del vector y de reservorios domésticos, así como determinación de asociación entre caso positivo y factores de riesgo bióticos y abióticos. El análisis estadístico consistió en índice Kappa para las pruebas diagnósticas, empleando tabla de contingencia de 2 x 2; ji cuadrada corregida de Yates, exacta de Fisher y la razón de posibilidad para estimar la significancia de la asociación de factores bióticos y abióticos. RESULTADOS: La seroprevalencia fue de 4% en la población humana estudiada y de los reservorios (equinos, porcinos y caninos), sólo 10% de los caninos resultaron reactivos. Los vectores identificados fueron T barberi y T pallidipennis, con índice de dispersión e índice de colonización de 55 y 40%, respectivamente. Los factores de riesgo más importantes fueron la altitud (>2 150 y <2 180 metros sobre el nivel del mar), los años de residencia, el pertenecer a un programa de asistencia social, la presencia de triatóminos y la edad. CONCLUSIONES: En localidades ubicadas a una altitud mayor a los 2 000 metros sobre el nivel del mar se reconocieron vectores infectados con T cruzi, casos humanos y probablemente reservorios domésticos.

OBJECTIVE: To establish the relationship between seroprevalence for antibodies against Trypanosoma cruzi and its relationship with biotic and abiotic factors. MATERIAL AND METHODS: A cross-sectional study was conducted between August 2000 and September 2001. The study population consisted of a simple random sample of 390 volunteers residing in Palmar de Bravo, Puebla, Mexico. Sample and data collection procedures included assaying antibodies against T cruzi with validated assays, and searching for domestic reservoirs and triatomine bugs. The relationship between biotic and abiotic factors with seropositivity was assessed. Statistical analysis was conducted using Kappa values for diagnostic tests; statistical significance was assessed with 2 x 2 tables, chi-squared test with Yates' correction, Fisher exact test, and odds ratios. RESULTS: The seroprevalence of T cruzi infection in humans was 4%; in domestic reservoirs (horses, pigs, and dogs) only 10% of canine reservoirs were positive. Vector species recognized were T barberi and T pallidipennis, with a Dispersion Area Index and a Colonization Index of 55% and 40%, respectively. The most important risk factors associated with positive serology were altitude (>2 150 y <2 180 meters above sea level), presence of triatomines, age, time of residence, and participation in a social assistance program. CONCLUSIONS: T cruzi infection was identified in human beings, vectors, and possibly in domestic reservoirs, in communities located over 2 000 meters above sea level.

OBJETIVO: Determinar la prevalencia de anticuerpos contra Trypanosoma cruzi y su relación con los factores bióticos y abióticos en Palmar de Bravo, Puebla, México. MATERIAL Y MÉTODOS: Estudio transversal efectuado en agosto de 2000 a septiembre de 2001, con una muestra aleatoria simple de 390 voluntarios residentes en Palmar de Bravo, Puebla, México. Se hizo determinación de anticuerpos contra T cruzi con técnicas serológicas validadas, búsqueda del vector y de reservorios domésticos, así como determinación de asociación entre caso positivo y factores de riesgo bióticos y abióticos. El análisis estadístico consistió en índice Kappa para las pruebas diagnósticas, empleando tabla de contingencia de 2 x 2; ji cuadrada corregida de Yates, exacta de Fisher y la razón de posibilidad para estimar la significancia de la asociación de factores bióticos y abióticos. RESULTADOS: La seroprevalencia fue de 4% en la población humana estudiada y de los reservorios (equinos, porcinos y caninos), sólo 10% de los caninos resultaron reactivos. Los vectores identificados fueron T barberi y T pallidipennis, con índice de dispersión e índice de colonización de 55 y 40%, respectivamente. Los factores de riesgo más importantes fueron la altitud (>2 150 y <2 180 metros sobre el nivel del mar), los años de residencia, el pertenecer a un programa de asistencia social, la presencia de triatóminos y la edad. CONCLUSIONES: En localidades ubicadas a una altitud mayor a los 2 000 metros sobre el nivel del mar se reconocieron vectores infectados con T cruzi, casos humanos y probablemente reservorios domésticos.

In México the first human chronic chagasic case was recognized in 1940. In spite of an increasing number of cases detected since that time, Chagas disease in México has been poorly documented. In the present work we studied 617 volunteers subjects living in high and low endemic regions of Trypanosoma cruzi infection with seroprevalence of 22% and 4% respectively. Hemoculture performed in those seropositive subjects failed to demonstrate circulating parasites, however polymerase chain reaction identified up to 60% of them as positives. A higher level of anti-T. cruzi antibodies was observed in seropositive residents in high endemic region, in spite of similar parasite persistence (p < 0.05). On standard 12 leads electrocardiogram (ECG) 20% to 22% seropositive individuals from either region showed right bundle branch block or ventricular extrasystoles which were more prevalent in seropositive than in seronegative individuals (p < 0.05). In conclusion, the frequency or type of ECG abnormality was influenced by serologic status but not by endemicity or parasite persistence. Furthermore, Mexican indeterminate patients have a similar ECG pattern to those reported in South America.