topeesp.gif (5672 bytes)

[ Index ]

CHAGAS-PCVC

Messages

Go to #: 64
Go to #: 63
Go to #: 62
Go to #: 61

#61 De: Joao Carlos Pinto Dias <jcpdias@cpqrr.fiocruz.br>
Enviado: Jueves 27 de Enero de 2000 08:30
Asunto: Re: Chagas con serologia no reactiva?/Re: Chagas with non reactive serology?
Sponsored by: Agilent Technologies
Querido Edgardo:
Inicialmente un gran abrazo. Esto es un caso tipico en  donde la clinica y la epidemiologia hablan muy alto. 3 consideraciones generales: a) en la practica, la conducta terapeutica no debe cambiar mucho en este caso, desde que el manejo clinico sera similar para Chagas o una dilatada idiopatica. No sera indicado el tratamiento especifico, debendose trabajar sobre la arritmia, la ICC y la posibilidad tromboembolica. Preguntamos   si hay signo o sospecha de mega asociado, lo que en mi pais ocurre en unos 10% de estos casos. (una evidencia positiva seria un elemento diagnostico adicional). b) Si, tenemos evidencia de cerca de 1% de casos de Chagas (comprobado parasitologicamente) con serologia reiteradamente negativa, lo que hace posible mantener la sospecha basada en los datos presentados; ademas ? que otra cardiomiopatia dilatada en joven de S. Estero, con BCRD/HBAI, aneurisma de punta y arritmia seria mas plausible que la ECh ? c) Tambien hay los rarisimos casos de ECh cronica que se negativizaron espontaneamente al largo del tiempo (Zeledon tiene 4 en C. Rica, hay 1 o 2 de Luquetti en Goias (Brasil) y recientemente otro se ha detectado en Uruguay (en prensa).
Como sugerencia diagnostica, insistir con la imunologia de punta (W. blot,monoclonales, anticuerpo litico), hacer el PCR y, si posible, aplicar 6 xenodiagnosticos y/o hemocultivos (numero de examenes que tendrala chance de detectar el parasito en cerca de 90% de los cronicos). Atentamente,

Dear Edgardo:
To begin with, a big hug. This is not a typical case, where clinic and epidemiology speak very loud. There are 3 general reflections to be made: a) in practice, therapeutic management must not change very much in this case, since clinical management will be similar for Chagas or an idiopathic dilated cardiomyopathy. Specific treatment will not be indicated, instead one should work on the arrhythmia, the CHF and the possibility of thromboembolism. We wonder if there is a sign or suspicion of megaviscera associated, that in my country happens in a 10% of these cases. (A positive evidence would be an additional diagnostic element.) b) Yes, we have evidence of about a 1% of cases of Chagas (parasitologically proven) with repeatedly negative serology, this makes possible to maintain a suspicion based in the presented data; besides, what other dilated cardiomyopathy in a young man from Santiago del Estero, with right ramus complete block/LAHB, apex aneurysm, and arrhythmia would be more possible than Chagas disease? c) There are also very rare cases of chronic Chagas disease that became negative spontaneously in long term (Zeledon has 4 in Costa Rica, there are 1 or 2 from Luquetti in Goias (Brazil), and recently another one was detected in Uruguay (in the media). As a diagnostic suggestion, insist with state-of-the-art immunology (W. Blot, monoclonal antibodies, lytic antibodies), perform PCR, and if possible, apply 6 xeno-diagnosis and/or hemo-cultures (amount of studies that will have the chance of detecting the parasite in around a 90% of chronic patients).
Sincerely,
Joao Carlos Pinto Dias

Top

#62 De:  Roberto Chuit <chuit@aya.yale.edu>
Enviado: Viernes 11 de Febrero de 2000 04:44 PM
Asunto: Chagas con serologia no reactiva?/Chagas with non reactive serology?
Sponsored by: Productos Roche
Estimados amigos y colegas
Me sumo a esta situacion en que si bien es de libro, a todos nos ha tocado tener que atender personas que cumplen los criterios de caso de una enfermedad y en la cual el laboratorio no acompana nuestro diagnostico presuntivo. En este caso en particular tenemos la clinica y la epidemiologia en consonancia, por lo cual hasta que se demuestre lo contrario es Chagas.
Otros estudios, siguiendo la linea de Anis Rassi en que el parasito si es buscado es encontrado permitiria sugerir su estudio, ya sea por la busquedadirecta (xenodiagnosticos seriados, etc que son dificultosos y pocos >realizan de manera correcta) o utilizar tecnicas alternativas (PCR- Dr. Mariano Levin del INGEBI-Arg entre otros tiene un metodo bastante bien ajustado y sencillo que rapidamente permitiria salir de dudas). Lo que si deberia dejarse en claro que estos estudios estan dirigidos a establecer una causalidad, pero que los mismos no cambiarian por el momento el crirerio o conducta terapeutica.
En resumen es una persona joven con lesiones miocardicas importantes, con diagnostico de Chagas hasta que se demuestre lo contrario, y que en consecuencia se puede considerar que no cambia la conducta terapeutica.
Saludos y a tu disposicion

Dear friends and colleagues:
I join to this situation that, even though is found in books, has happened to all of us, that is to say to treat individuals that meet the criteria of  the case for a disease, and in whom the laboratory does not accompany our supposed diagnosis. In this particular case, we have the clinic and  the epidemiology in agreement, consequently until the contrary is proved, this is Chagas.
Other studies, following the line of Anis Rassi, in  which if the parasite is sought for, it is found, would allow us to suggest its study, whether by direct search (serial xenodiagnosis, etc. that are difficult and a few make them properly) or by using the alternative techniques (PCR - Dr. Mariano Levin from INGEBI-Arg among others, employs a method quite well adjusted and simple that would allow us to clear doubts quickly). In fact, what we should clarify is that these studies have the purpose of establishing a causality, but that they would not change momentarily the therapeutic criterion or management.
Summarizing, this is a young person with important myocardial lesions, with diagnosis of Chagas until the contrary is proven, and consequently, we may assume that the therapeutic management does not change.
Greetings, and I remain at your disposal
Dr Roberto Chuit

Top

#63 De: Maria Cristina Vazquez
Enviado: Sabado 12 de Febrero de 2000 09:13
Asunto: Chagas con serologia no reactiva?/Chagas with non reactive serology?
Sponsored by: Deutsche Bank
Estimado Dr. Chuit , es muy interesante su comunicación .
Pregunto a la lista si se le realizó PCR a este paciente para poder acercaarnos más al diagnóstico.
Lo saluda MC Vázquez

Dear Dr. Chuit:
Your communication is very interesting.
I ask to the list if PCR was carried out on this patient, for us to be able to get closer to diagnosis.
Greetings,
MC Vázquez
Bs As Argentina

Top

#64 De: Manzullo Enrique
Enviado: Lunes 14 de Febrero de 2000 07:48 PM
Asunto: Cardiopatia chagasica?/Chagasic heart disease?
Sponsored by: Laboratorios Gador
Estimado Edgardo y amigos colegas:
En relacion al paciente con cardiopatia y serologia negativa para Chagas (santiagueno- de La Banda), coincido con los expresado por Joao Carlos y Chuit... en general. En nuestro sewguimiento de aproximadamente 5000 reactores positivos hemos visto 12 que negativizaron la serologia de dos a 6 anos. No dependio de tratamiento alguno y ninguno quedo con serologia negativa mas de 6 anos.
Algunos tenian evidencias de miocardiopatia y otros no. Si alguno de ellos nos hubiera llegado con cardiopatia dilatada en la etapa de serologia negativa hubieramos estado con el mismo problema que aqui se plantea y con seguridad hubieramos actuado sobre la cardiopatia, tal cual lo comentan los colegas. Que otra opcion?. Esta es la parte en que coincido. Sin embargo la pregunta es: Chagas o nada?. Las miocardiopatias dilatadas estan presentes en todas partes del mundo. En EE.UU se senala una prevalencia de 20/100000 (Caforio,A.L, BMJ. 1990; 300: 890-891) En Chile Arribada y Apt en su libro : CArdiopatias parasitarias, (U. de Chile 1980) realiza numerosas observaciones sobre estas afecciones (Ej.: Toxoplasmosis).
Existe muchisima bibligrafia sobre miocardiopatias de aspecto parecido , en edad ,alteraciones ECG y Eco que no se pudieron dilucidar en su etiologia en zonas sin Chagas. Donde existe Chagas no puede haber otras causas, que provoquen similares alteraciones cardiacas?. Como vamos a investigarlas si los suponemos chagasicos negativos. En mas de 20 anos, de buscar en infecciones cronicas indicios de miocardiopatia hemos podido diagnosticar muy pocas (toxoplasmosis, hepatits B ). Sin embargo si hemos observado numerosas micarditis en enf. infecciosas agudas, la mayoria en forma subclinica. Como resultado, algunos tienen muerte subita en convalescencia, y la mayoria cura sin secuela. Unos pocos quedan con secuelas ( BCRD, inactivaciones y/o T. primarios de Rep.). Los seguimentos fueron de pocos meses, pero sin la H. Clinica nos resulta imposible reconocer su etilogia. Como evolucionaron años despues?.
Estimado Edgardo, tal vez los colegas tengan razon y tu paciente resulte chagasico con serologia negativa, pero como tu has dicho : medicina  por evidencias. Me atrevo a sugerirles a tus residentes que lean bibliografia sobre otras causas infecciosas y no infecciosas y soliciten estudios de otras afecciones. Si no llegan a nada el diagnostico sera mocardiopatia de causa desconocida.
Cordialmente.

Dear Edgardo and colleagues and friends:
About the patient with heart disease and negative serology for Chagas (from La Banda - Santiago del Estero), I agree with what has been expressed by Joao Carlos and Chuit... in general. In our follow up on approximately 5000 positive reactive patients, we have seen 12 whoseserology became negative for two to 6 years. This did not depend on any treatment, and none remained with negative serology for more than 6 years. Some displayed evidence of cardiomyopathy, and others did not. If any of them would have arrived with dilated cardiomyopathy in the stage in which serology was negative, we would have been in the same problem posed here, and surely we would have acted on the cardiomyopathy, just as the colleagues mention. What other option there is? This is that part in which I agree. However, the question is: Chagas or nothing? Dilated cardiomyopathies are present all over the world. In USA a prevalence of 20/100000 is reported (Caforio, A.L, BMJ. 1990; 300: 890-891). In Chile, Arribada and Apt in his book: "Cardiopatias parasitarias" (U. de Chile 1980), made several commentaries on these conditions (e.g.: toxoplasmosis). There is plenty of bibliography on cardiomyopathies with similar appearance, in age, ECG and echo alterations that could not be clarified in their etiology in areas without Chagas. Where there is Chagas, could there be no other causes for similar cardiac alterations? How are we going to investigate them if we assume them to be negative chagasic patients. In more than 20 years of searching indications of cardiomyopathy in chronic infections, we could diagnose very few (toxoplasmosis, hepatitis B). However, we have observed several myocarditis in acute infectious diseases, most of them in subclinical form. As a result, some suffer sudden death during convalescence, and most get cured without sequels. A few have sequels (right ramus complete block, inactivation and/or primary disorders of repolarization) Follow ups were carried out for few months, but without clinical history it is impossible for us to reckon their etiology. How did they evolve years afterwards?
Dear Edgardo, maybe the colleagues are right, and your patient turns out to be chagasic with negative serology, but as you said: medicine through evidence. Let me suggest to your interns to read bibliography on other infectious and non infectious causes, and to request studies on other conditions. If they can reach no conclusion, the diagnosis will be cardiomyopathy with unknown causes.
Cordially,
Enrique Manzullo

Top


© CETIFAC
Bioengineering
UNER

Update
Feb/17/2000