ELISA versus PCR for diagnosis of chronic Chagas disease: systematic review and meta-analysis

<p>Abstract</p> <p>Background</p> <p>Most current guidelines recommend two serological tests to diagnose chronic Chagas disease. When serological tests are persistently inconclusive, some guidelines recommend molecular tests. The aim of this investigation was to review chronic Chagas disease diagnosis literature and to summarize results of ELISA and PCR performance.</p> <p>Methods</p> <p>A systematic review was conducted searching remote databases (MEDLINE, LILACS, EMBASE, SCOPUS and ISIWeb) and full texts bibliography for relevant abstracts. In addition, manufacturers of commercial tests were contacted. Original investigations were eligible if they estimated sensitivity and specificity, or reliability -or if their calculation was possible - of ELISA or PCR tests, for chronic Chagas disease.</p> <p>Results</p> <p>Heterogeneity was high within each test (ELISA and PCR) and threshold effect was detected only in a particular subgroup. Reference standard blinding partially explained heterogeneity in ELISA studies, and pooled sensitivity and specificity were 97.7% [96.7%-98.5%] and 96.3% [94.6%-97.6%] respectively. Commercial ELISA with recombinant antigens studied in phase three investigations partially explained heterogeneity, and pooled sensitivity and specificity were 99.3% [97.9%-99.9%] and 97.5% [88.5%-99.5%] respectively. ELISA's reliability was seldom studied but was considered acceptable. PCR heterogeneity was not explained, but a threshold effect was detected in three groups created by using guanidine and boiling the sample before DNA extraction. PCR sensitivity is likely to be between 50% and 90%, while its specificity is close to 100%. PCR reliability was never studied.</p> <p>Conclusions</p> <p>Both conventional and recombinant based ELISA give useful information, however there are commercial tests without technical reports and therefore were not included in this review. Physicians need to have access to technical reports to understand if these serological tests are similar to those included in this review and therefore correctly order and interpret test results. Currently, PCR should not be used in clinical practice for chronic Chagas disease diagnosis and there is no PCR test commercially available for this purpose. Tests limitations and directions for future research are discussed.</p

Memorias de Hacienda y del Tesoro y de la Nueva Granada y Colombia, siglo XIX

En este libro digital el Banco de la República pone a disposición de los investigadores y bibliotecas del país la totalidad de las memorias de Hacienda y Tesoro colombianas que se publicaron en el siglo XIX. Es una herramienta bibliográfica que esperamos sea de enorme utilidad para los profesionales, estudiantes y amantes de la historia de Colombia. El célebre economista austriaco Joseph Schumpeter sostenía que las finanzas públicas son uno de los mejores puntos de partida para investigar una sociedad: allí se reflejan la riqueza, su distribución territorial y sectorial, la marcha de la actividad económica, las prioridades en el gasto y sus beneficiarios. Por su relevancia, y por cuanto los ciudadanos quieren saber en qué se gastan los impuestos que han pagado, los gobiernos democráticos han sido cuidadosos en la rendición de informes periódicos sobre los recaudos, los gastos, los excedentes o déficits en las finanzas gubernamentales y las formas de cubrir estos últimos. Para ello, con cierta regularidad se presentan informes a los órganos de control político o administrativo. Por esa razón, en el Banco de la República hemos considerado que un aporte bibliográfico de gran relevancia para el estudio de la historia económica nacional es poner a disposición de los investigadores y bibliotecas del país esta edición digital de las memorias de Hacienda y Tesoro del siglo XIX