title: In-house ELISA method to analyze anti-Trypanosoma cruzi IgG reactivity for differential diagnosis and evaluation of Chagas disease morbidity.
abstract: BACKGROUND
  The goal was to develop an in-house serological method with high specificity and sensitivity for diagnosis and monitoring of Chagas disease morbidity.
  
  
  METHODS
  With this purpose, the reactivities of anti-T. cruzi IgG and subclasses were tested in successive serum dilutions of patients from Berilo municipality, Jequitinhonha Valley, Minas Gerais, Brazil. The performance of the in-house ELISA was also evaluated in samples from other relevant infectious diseases, including HIV, hepatitis C (HCV), syphilis (SYP), visceral leishmaniasis (VL), and American tegumentary leishmaniasis (ATL), and noninfected controls (NI). Further analysis was performed to evaluate the applicability of this in-house methodology for monitoring Chagas disease morbidity into three groups of patients: indeterminate (IND), cardiac (CARD), and digestive/mixed (DIG/Mix), based on their clinical status.
  
  
  RESULTS
  The analysis of total IgG reactivity at serum dilution 1:40 was an excellent approach to Chagas disease diagnosis (100% sensitivity and specificity). The analysis of IgG subclasses showed cross-reactivity, mainly with NI, VL, and ATL, at all selected serum dilutions. Based on the data analysis, the IND group displayed higher IgG3 levels and the DIG/Mix group presented higher levels of total IgG as compared with the IND and CARD groups.
  
  
  CONCLUSIONS
  These findings demonstrated that methodology presents promising applicability in the analysis of anti-T. cruzi IgG reactivity for the differential diagnosis and evaluation of Chagas disease morbidity.
authors.affiliation: Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG.
authors.forename: Lilian da Silva
authors.initials: Lda S
authors.lastname: Santos
authors.forename: Rosália Morais
authors.initials: RM
authors.lastname: Torres
authors.forename: Girley Francisco
authors.initials: GF
authors.lastname: Machado-de-Assis
authors.forename: Maria Terezinha
authors.initials: MT
authors.lastname: Bahia
authors.forename: Helen Rodrigues
authors.initials: HR
authors.lastname: Martins
authors.forename: Andréa
authors.initials: A
authors.lastname: Teixeira-Carvalho
authors.forename: Jordana Grazziela Alves
authors.initials: JG
authors.lastname: Coelho-Dos-Reis
authors.forename: Pedro
authors.initials: P
authors.lastname: Albajar-Viñas
authors.forename: Olindo Assis
authors.initials: OA
authors.lastname: Martins-Filho
authors.forename: Marta de
authors.initials: Md
authors.lastname: Lana
mesh_terms: D000293:Adolescent; D000328:Adult; D000913:Antibodies, Protozoan / Q000097:blood / Q000276:immunology*; D000937:Antigen-Antibody Reactions; D002598:Chagas Cardiomyopathy / Q000175:diagnosis; D014355:Chagas Disease / Q000150:complications / Q000175:diagnosis*; D003937:Diagnosis, Differential; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014349:Trypanosoma cruzi / Q000276:immunology*; D055815:Young Adult
chemical_list: D000913:Antibodies, Protozoan; D007074:Immunoglobulin G